CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Aquifer - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"f7c08368-eee5-482d-9513-58f4cc12350b","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Aquifer","wgTitle":"Aquifer","wgCurRevisionId":1255804936,"wgRevisionId":1255804936,"wgArticleId":47481,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Webarchive template wayback links","Articles with short description","Short description is different from Wikidata","Articles with excerpts","Pages displaying short descriptions of redirect targets via Module:Annotated link","Aquifers","Hydraulic engineering","Hydrology","Hydrogeology","Water and the environment","Bodies of water","Water supply"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Aquifer","wgRelevantArticleId":47481, "wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":30000,"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q208791","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"], "GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","mediawiki.page.media","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar", "ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.quicksurveys.init","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/1200px-Groundwater_flow.svg.png"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="744"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/800px-Groundwater_flow.svg.png"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="496"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/640px-Groundwater_flow.svg.png"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="397"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Aquifer - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Aquifer"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Aquifer&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Aquifer"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Aquifer rootpage-Aquifer skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Aquifer" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Aquifer" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Aquifer" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Aquifer" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Properties" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Properties"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Properties</span> </div> </a> <button aria-controls="toc-Properties-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Properties subsection</span> </button> <ul id="toc-Properties-sublist" class="vector-toc-list"> <li id="toc-Depth" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Depth"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Depth</span> </div> </a> <ul id="toc-Depth-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Groundwater_recharge" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Groundwater_recharge"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Groundwater recharge</span> </div> </a> <ul id="toc-Groundwater_recharge-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Classification" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Classification"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Classification</span> </div> </a> <button aria-controls="toc-Classification-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Classification subsection</span> </button> <ul id="toc-Classification-sublist" class="vector-toc-list"> <li id="toc-Saturated_versus_unsaturated" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Saturated_versus_unsaturated"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Saturated versus unsaturated</span> </div> </a> <ul id="toc-Saturated_versus_unsaturated-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Aquifers_versus_aquitards" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Aquifers_versus_aquitards"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Aquifers versus aquitards</span> </div> </a> <ul id="toc-Aquifers_versus_aquitards-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Confined_versus_unconfined" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Confined_versus_unconfined"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Confined versus unconfined</span> </div> </a> <ul id="toc-Confined_versus_unconfined-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Isotropic_versus_anisotropic" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Isotropic_versus_anisotropic"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4</span> <span>Isotropic versus anisotropic</span> </div> </a> <ul id="toc-Isotropic_versus_anisotropic-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Porous,_karst,_or_fractured" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Porous,_karst,_or_fractured"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5</span> <span>Porous, karst, or fractured</span> </div> </a> <ul id="toc-Porous,_karst,_or_fractured-sublist" class="vector-toc-list"> <li id="toc-Porous" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Porous"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5.1</span> <span>Porous</span> </div> </a> <ul id="toc-Porous-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Karst" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Karst"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5.2</span> <span>Karst</span> </div> </a> <ul id="toc-Karst-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Fractured" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Fractured"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5.3</span> <span>Fractured</span> </div> </a> <ul id="toc-Fractured-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Human_use_of_groundwater" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Human_use_of_groundwater"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Human use of groundwater</span> </div> </a> <ul id="toc-Human_use_of_groundwater-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-By_country_or_continent" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#By_country_or_continent"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>By country or continent</span> </div> </a> <button aria-controls="toc-By_country_or_continent-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle By country or continent subsection</span> </button> <ul id="toc-By_country_or_continent-sublist" class="vector-toc-list"> <li id="toc-Africa" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Africa"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Africa</span> </div> </a> <ul id="toc-Africa-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Australia" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Australia"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Australia</span> </div> </a> <ul id="toc-Australia-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Canada" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Canada"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Canada</span> </div> </a> <ul id="toc-Canada-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-South_America" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#South_America"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>South America</span> </div> </a> <ul id="toc-South_America-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-United_States" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#United_States"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>United States</span> </div> </a> <ul id="toc-United_States-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Aquifer</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 56 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-56" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">56 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B7%D8%A8%D9%82%D8%A9_%D8%A7%D9%84%D9%85%D9%8A%D8%A7%D9%87_%D8%A7%D9%84%D8%AC%D9%88%D9%81%D9%8A%D8%A9" title="طبقة المياه الجوفية – Arabic" lang="ar" hreflang="ar" data-title="طبقة المياه الجوفية" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Acuifero" title="Acuifero – Aragonese" lang="an" hreflang="an" data-title="Acuifero" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%D8%A2%DA%A9%DB%8C%D9%81%D8%B1" title="آکیفر – South Azerbaijani" lang="azb" hreflang="azb" data-title="آکیفر" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%AD%E0%A7%82%E0%A6%97%E0%A6%B0%E0%A7%8D%E0%A6%AD%E0%A6%B8%E0%A7%8D%E0%A6%A5_%E0%A6%B8%E0%A6%BF%E0%A6%95%E0%A7%8D%E0%A6%A4_%E0%A6%B6%E0%A6%BF%E0%A6%B2%E0%A6%BE%E0%A6%B8%E0%A7%8D%E0%A6%A4%E0%A6%B0" title="ভূগর্ভস্থ সিক্ত শিলাস্তর – Bangla" lang="bn" hreflang="bn" data-title="ভূগর্ভস্থ সিক্ত শিলাস্তর" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%92%D0%BE%D0%B4%D0%BE%D0%BD%D0%BE%D1%81%D0%B5%D0%BD_%D1%85%D0%BE%D1%80%D0%B8%D0%B7%D0%BE%D0%BD%D1%82" title="Водоносен хоризонт – Bulgarian" lang="bg" hreflang="bg" data-title="Водоносен хоризонт" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Aq%C3%BC%C3%ADfer" title="Aqüífer – Catalan" lang="ca" hreflang="ca" data-title="Aqüífer" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Zvode%C5%88" title="Zvodeň – Czech" lang="cs" hreflang="cs" data-title="Zvodeň" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Grundvandsmagasin" title="Grundvandsmagasin – Danish" lang="da" hreflang="da" data-title="Grundvandsmagasin" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Grundwasserleiter" title="Grundwasserleiter – German" lang="de" hreflang="de" data-title="Grundwasserleiter" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-nv mw-list-item"><a href="https://nv.wikipedia.org/wiki/%C5%81eeyi%CA%BCdi_t%C3%B3h%C3%ADg%C3%AD%C3%AD" title="Łeeyiʼdi tóhígíí – Navajo" lang="nv" hreflang="nv" data-title="Łeeyiʼdi tóhígíí" data-language-autonym="Diné bizaad" data-language-local-name="Navajo" class="interlanguage-link-target"><span>Diné bizaad</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/P%C3%B5hjaveekiht" title="Põhjaveekiht – Estonian" lang="et" hreflang="et" data-title="Põhjaveekiht" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Grundakvejo" title="Grundakvejo – Esperanto" lang="eo" hreflang="eo" data-title="Grundakvejo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Akuifero" title="Akuifero – Basque" lang="eu" hreflang="eu" data-title="Akuifero" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A2%D8%A8%D8%AE%D9%88%D8%A7%D9%86" title="آبخوان – Persian" lang="fa" hreflang="fa" data-title="آبخوان" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Aquif%C3%A8re" title="Aquifère – French" lang="fr" hreflang="fr" data-title="Aquifère" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Uisc%C3%ADoch" title="Uiscíoch – Irish" lang="ga" hreflang="ga" data-title="Uiscíoch" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Acu%C3%ADfero" title="Acuífero – Galician" lang="gl" hreflang="gl" data-title="Acuífero" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%8C%80%EC%88%98%EC%B8%B5" title="대수층 – Korean" lang="ko" hreflang="ko" data-title="대수층" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%9C%E0%A4%B2%E0%A4%AD%E0%A4%B0" title="जलभर – Hindi" lang="hi" hreflang="hi" data-title="जलभर" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Akuifer" title="Akuifer – Indonesian" lang="id" hreflang="id" data-title="Akuifer" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Falda_acquifera" title="Falda acquifera – Italian" lang="it" hreflang="it" data-title="Falda acquifera" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%90%D7%A7%D7%95%D7%95%D7%94" title="אקווה – Hebrew" lang="he" hreflang="he" data-title="אקווה" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%9C%E0%B2%B2%E0%B2%A7%E0%B2%B0" title="ಜಲಧರ – Kannada" lang="kn" hreflang="kn" data-title="ಜಲಧರ" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%AC%E1%83%A7%E1%83%9A%E1%83%98%E1%83%90%E1%83%9C%E1%83%98_%E1%83%B0%E1%83%9D%E1%83%A0%E1%83%98%E1%83%96%E1%83%9D%E1%83%9C%E1%83%A2%E1%83%98" title="წყლიანი ჰორიზონტი – Georgian" lang="ka" hreflang="ka" data-title="წყლიანი ჰორიზონტი" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%96%D0%B5%D1%80%D0%B3%D1%96%D0%BB%D1%96%D0%BA%D1%82%D1%96_%D1%81%D1%83%D0%BB%D0%B0%D1%80" title="Жергілікті сулар – Kazakh" lang="kk" hreflang="kk" data-title="Жергілікті сулар" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Akwif%C3%A8" title="Akwifè – Haitian Creole" lang="ht" hreflang="ht" data-title="Akwifè" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Stratum_aquiferum" title="Stratum aquiferum – Latin" lang="la" hreflang="la" data-title="Stratum aquiferum" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Vandeningas_sluoksnis" title="Vandeningas sluoksnis – Lithuanian" lang="lt" hreflang="lt" data-title="Vandeningas sluoksnis" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/Aves" title="Aves – Lombard" lang="lmo" hreflang="lmo" data-title="Aves" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Akuifer" title="Akuifer – Malay" lang="ms" hreflang="ms" data-title="Akuifer" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%A3%D1%81%D1%82_%D0%B4%D0%B0%D0%B2%D1%85%D0%B0%D1%80%D0%B3%D0%B0" title="Уст давхарга – Mongolian" lang="mn" hreflang="mn" data-title="Уст давхарга" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Aquifer" title="Aquifer – Dutch" lang="nl" hreflang="nl" data-title="Aquifer" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E5%B8%AF%E6%B0%B4%E5%B1%A4" title="帯水層 – Japanese" lang="ja" hreflang="ja" data-title="帯水層" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Akvifer" title="Akvifer – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Akvifer" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Warstwa_wodono%C5%9Bna" title="Warstwa wodonośna – Polish" lang="pl" hreflang="pl" data-title="Warstwa wodonośna" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Aqu%C3%ADfero" title="Aquífero – Portuguese" lang="pt" hreflang="pt" data-title="Aquífero" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Acvifer" title="Acvifer – Romanian" lang="ro" hreflang="ro" data-title="Acvifer" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%92%D0%BE%D0%B4%D0%BE%D0%BD%D0%BE%D1%81%D0%BD%D1%8B%D0%B9_%D0%B3%D0%BE%D1%80%D0%B8%D0%B7%D0%BE%D0%BD%D1%82" title="Водоносный горизонт – Russian" lang="ru" hreflang="ru" data-title="Водоносный горизонт" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%A2%E0%B6%BD%E0%B6%B0%E0%B6%BB" title="ජලධර – Sinhala" lang="si" hreflang="si" data-title="ජලධර" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Aquifer" title="Aquifer – Simple English" lang="en-simple" hreflang="en-simple" data-title="Aquifer" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Hydrologick%C3%BD_kolektor" title="Hydrologický kolektor – Slovak" lang="sk" hreflang="sk" data-title="Hydrologický kolektor" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Vodonosnik" title="Vodonosnik – Slovenian" lang="sl" hreflang="sl" data-title="Vodonosnik" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D8%A6%D8%A7%D9%88%DA%BE%DB%95%DA%B5%DA%AF%D8%B1" title="ئاوھەڵگر – Central Kurdish" lang="ckb" hreflang="ckb" data-title="ئاوھەڵگر" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%98%D0%B7%D0%B4%D0%B0%D0%BD" title="Издан – Serbian" lang="sr" hreflang="sr" data-title="Издан" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Izdan" title="Izdan – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Izdan" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/Aquifer" title="Aquifer – Sundanese" lang="su" hreflang="su" data-title="Aquifer" data-language-autonym="Sunda" data-language-local-name="Sundanese" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-fi badge-Q70894304 mw-list-item" title=""><a href="https://fi.wikipedia.org/wiki/Akviferi" title="Akviferi – Finnish" lang="fi" hreflang="fi" data-title="Akviferi" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Akvifer" title="Akvifer – Swedish" lang="sv" hreflang="sv" data-title="Akvifer" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%A8%E0%AE%BF%E0%AE%B2%E0%AE%A4%E0%AF%8D%E0%AE%A4%E0%AE%9F%E0%AE%BF_%E0%AE%A8%E0%AF%80%E0%AE%B0%E0%AF%8D%E0%AE%AA%E0%AF%8D%E0%AE%AA%E0%AE%9F%E0%AF%81%E0%AE%95%E0%AF%88" title="நிலத்தடி நீர்ப்படுகை – Tamil" lang="ta" hreflang="ta" data-title="நிலத்தடி நீர்ப்படுகை" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%8A%E0%B8%B1%E0%B9%89%E0%B8%99%E0%B8%AB%E0%B8%B4%E0%B8%99%E0%B8%AD%E0%B8%B8%E0%B9%89%E0%B8%A1%E0%B8%99%E0%B9%89%E0%B8%B3" title="ชั้นหินอุ้มน้ำ – Thai" lang="th" hreflang="th" data-title="ชั้นหินอุ้มน้ำ" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Akifer" title="Akifer – Turkish" lang="tr" hreflang="tr" data-title="Akifer" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-kcg mw-list-item"><a href="https://kcg.wikipedia.org/wiki/A%CC%B1swom_(a%CC%B1sa%CC%B1khwot)" title="A̱swom (a̱sa̱khwot) – Tyap" lang="kcg" hreflang="kcg" data-title="A̱swom (a̱sa̱khwot)" data-language-autonym="Tyap" data-language-local-name="Tyap" class="interlanguage-link-target"><span>Tyap</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%92%D0%BE%D0%B4%D0%BE%D0%BD%D0%BE%D1%81%D0%BD%D0%B8%D0%B9_%D0%B3%D0%BE%D1%80%D0%B8%D0%B7%D0%BE%D0%BD%D1%82" title="Водоносний горизонт – Ukrainian" lang="uk" hreflang="uk" data-title="Водоносний горизонт" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%B2%DB%8C%D8%B1_%D8%B2%D9%85%DB%8C%D9%86_%D8%A2%D8%A8%DB%8C_%D8%B0%D8%AE%DB%8C%D8%B1%DB%81" title="زیر زمین آبی ذخیرہ – Urdu" lang="ur" hreflang="ur" data-title="زیر زمین آبی ذخیرہ" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/T%E1%BA%A7ng_ng%E1%BA%ADm_n%C6%B0%E1%BB%9Bc" title="Tầng ngậm nước – Vietnamese" lang="vi" hreflang="vi" data-title="Tầng ngậm nước" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%90%AB%E6%B0%B4%E5%B1%82" title="含水层 – Chinese" lang="zh" hreflang="zh" data-title="含水层" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q208791#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Aquifer" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Aquifer" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Aquifer"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Aquifer&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Aquifer&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Aquifer"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Aquifer&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Aquifer&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Aquifer" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Aquifer" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Aquifer&oldid=1255804936" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Aquifer&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Aquifer&id=1255804936&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAquifer"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAquifer"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Aquifer&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Aquifer&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="wb-otherproject-link wb-otherproject-commons mw-list-item"><a href="https://commons.wikimedia.org/wiki/Category:Aquifers" hreflang="en"><span>Wikimedia Commons</span></a></li><li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q208791" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Underground layer of water-bearing permeable rock</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Groundwater_flow.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/400px-Groundwater_flow.svg.png" decoding="async" width="400" height="248" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/600px-Groundwater_flow.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Groundwater_flow.svg/800px-Groundwater_flow.svg.png 2x" data-file-width="645" data-file-height="400" /></a><figcaption>Schematic of an aquifer showing confined zones, <a href="/wiki/Groundwater" title="Groundwater">groundwater</a> travel times, a <a href="/wiki/Spring_(hydrology)" title="Spring (hydrology)">spring</a> and a <a href="/wiki/Well" title="Well">well</a></figcaption></figure> <p>An <b>aquifer</b> is an underground layer of <a href="/wiki/Water" title="Water">water</a>-bearing material, consisting of <a href="/wiki/Permeability_(Earth_sciences)" class="mw-redirect" title="Permeability (Earth sciences)">permeable</a> or fractured rock, or of unconsolidated materials (<a href="/wiki/Gravel" title="Gravel">gravel</a>, <a href="/wiki/Sand" title="Sand">sand</a>, or <a href="/wiki/Silt" title="Silt">silt</a>). Aquifers vary greatly in their characteristics. The study of water flow in aquifers and the characterization of aquifers is called <a href="/wiki/Hydrogeology" title="Hydrogeology">hydrogeology</a>. Related terms include <b>aquitard</b>, which is a bed of low permeability along an aquifer, and <b>aquiclude</b> (or <i>aquifuge</i>), which is a solid, impermeable area underlying or overlying an aquifer, the pressure of which could lead to the formation of a confined aquifer. The classification of aquifers is as follows: Saturated versus unsaturated; aquifers versus aquitards; confined versus unconfined; isotropic versus anisotropic; porous, karst, or fractured; transboundary aquifer. </p><p><a href="/wiki/Groundwater" title="Groundwater">Groundwater</a> from aquifers can be sustainably harvested by humans through the use of <a href="/wiki/Qanats" class="mw-redirect" title="Qanats">qanats</a> leading to a well.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> This groundwater is a major source of fresh water for many regions, however can present a number of challenges such as <a href="/wiki/Overdrafting" title="Overdrafting">overdrafting</a> (extracting groundwater beyond the <a href="/wiki/Dynamic_equilibrium" title="Dynamic equilibrium">equilibrium</a> yield of the aquifer), <a href="/wiki/Groundwater-related_subsidence" title="Groundwater-related subsidence">groundwater-related subsidence</a> of land, and the <a href="/wiki/Freshwater_salinization" title="Freshwater salinization">salinization</a> or <a href="/wiki/Groundwater_pollution" title="Groundwater pollution">pollution</a> of the groundwater. </p> <style data-mw-deduplicate="TemplateStyles:r886046785">.mw-parser-output .toclimit-2 .toclevel-1 ul,.mw-parser-output .toclimit-3 .toclevel-2 ul,.mw-parser-output .toclimit-4 .toclevel-3 ul,.mw-parser-output .toclimit-5 .toclevel-4 ul,.mw-parser-output .toclimit-6 .toclevel-5 ul,.mw-parser-output .toclimit-7 .toclevel-6 ul{display:none}</style><div class="toclimit-3"><meta property="mw:PageProp/toc" /></div> <div class="mw-heading mw-heading2"><h2 id="Properties">Properties</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=1" title="Edit section: Properties"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Aquifer_properties" title="Aquifer properties">Aquifer properties</a></div> <div class="mw-heading mw-heading3"><h3 id="Depth">Depth</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=2" title="Edit section: Depth"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Aquifer_en.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/04/Aquifer_en.svg/350px-Aquifer_en.svg.png" decoding="async" width="350" height="346" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/04/Aquifer_en.svg/525px-Aquifer_en.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/04/Aquifer_en.svg/700px-Aquifer_en.svg.png 2x" data-file-width="672" data-file-height="665" /></a><figcaption>An aquifer cross-section. This diagram shows two aquifers with one aquitard (a confining or impermeable layer) between them, surrounded by the bedrock <i>aquiclude</i>, which is in contact with a gaining <a href="/wiki/Stream" title="Stream">stream</a> (typical in <a href="/wiki/Humid" class="mw-redirect" title="Humid">humid</a> regions). The water table and <a href="/wiki/Vadose_zone" title="Vadose zone">unsaturated zone</a> are also illustrated.</figcaption></figure> <p>Aquifers occur from near-surface to deeper than 9,000 metres (30,000 ft).<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Those closer to the surface are not only more likely to be used for water supply and irrigation, but are also more likely to be replenished by local rainfall. Although aquifers are sometimes characterized as "underground rivers or lakes," they are actually porous rock saturated with water.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>Many desert areas have <a href="/wiki/Limestone" title="Limestone">limestone</a> <a href="/wiki/Hills" class="mw-redirect" title="Hills">hills</a> or mountains within them or close to them that can be exploited as groundwater resources.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Part of the <a href="/wiki/Atlas_Mountains" title="Atlas Mountains">Atlas Mountains</a> in North Africa, the <a href="/wiki/Mount_Lebanon" title="Mount Lebanon">Lebanon</a> and <a href="/wiki/Anti-Lebanon" class="mw-redirect" title="Anti-Lebanon">Anti-Lebanon</a> ranges between Syria and Lebanon, the <a href="/wiki/Jebel_Akhdar_(Oman)" title="Jebel Akhdar (Oman)">Jebel Akhdar</a> in Oman, parts of the <a href="/wiki/Sierra_Nevada_(U.S.)" class="mw-redirect" title="Sierra Nevada (U.S.)">Sierra Nevada</a> and neighboring ranges in the <a href="/wiki/Southwestern_United_States" title="Southwestern United States">United States' Southwest</a>, have shallow aquifers that are exploited for their water. <a href="/wiki/Overexploitation" title="Overexploitation">Overexploitation</a> can lead to the exceeding of the practical sustained yield; i.e., more water is taken out than can be replenished. </p><p>Along the coastlines of certain countries, such as <a href="/wiki/Libya" title="Libya">Libya</a> and Israel, increased water usage associated with population growth has caused a lowering of the <a href="/wiki/Water_table" title="Water table">water table</a> and the subsequent <a href="/wiki/Saltwater_intrusion" title="Saltwater intrusion">contamination of the groundwater with saltwater</a> from the sea. </p><p>In 2013 large freshwater aquifers were discovered under continental shelves off Australia, China, North America and South Africa. They contain an estimated half a million cubic kilometers of "low salinity" water that could be economically processed into <a href="/wiki/Drinking_water" title="Drinking water">potable water</a>. The reserves formed when ocean levels were lower and rainwater made its way into the ground in land areas that were not submerged until the <a href="/wiki/Ice_age" title="Ice age">ice age</a> ended 20,000 years ago. The volume is estimated to be 100 times the amount of water extracted from other aquifers since 1900.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Groundwater_recharge">Groundwater recharge</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=3" title="Edit section: Groundwater recharge"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="excerpt-block"><style data-mw-deduplicate="TemplateStyles:r1066933788">.mw-parser-output .excerpt-hat .mw-editsection-like{font-style:normal}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable dablink excerpt-hat selfref">This section is an excerpt from <a href="/wiki/Groundwater_recharge" title="Groundwater recharge">Groundwater recharge</a>.<span class="mw-editsection-like plainlinks"><span class="mw-editsection-bracket">[</span><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Groundwater_recharge&action=edit">edit</a><span class="mw-editsection-bracket">]</span></span></div><div class="excerpt"> <a href="/wiki/Groundwater_recharge" title="Groundwater recharge">Groundwater recharge</a> or deep drainage or deep percolation is a <a href="/wiki/Hydrology" title="Hydrology">hydrologic</a> process, where <a href="/wiki/Water" title="Water">water</a> moves downward from <a href="/wiki/Surface_water" title="Surface water">surface water</a> to <a href="/wiki/Groundwater" title="Groundwater">groundwater</a>. Recharge is the primary method through which water enters an aquifer. This process usually occurs in the <a href="/wiki/Vadose_zone" title="Vadose zone">vadose zone</a> below plant <a href="/wiki/Root" title="Root">roots</a> and is often expressed as a <a href="/wiki/Flux" title="Flux">flux</a> to the <a href="/wiki/Water_table" title="Water table">water table</a> surface. Groundwater recharge also encompasses water moving away from the water table farther into the saturated zone.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> Recharge occurs both naturally (through the <a href="/wiki/Water_cycle" title="Water cycle">water cycle</a>) and through anthropogenic processes (i.e., "artificial groundwater recharge"), where rainwater and/or <a href="/wiki/Reclaimed_water" title="Reclaimed water">reclaimed water</a> is routed to the subsurface.</div></div> <div class="mw-heading mw-heading2"><h2 id="Classification">Classification</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=4" title="Edit section: Classification"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An <i><a href="https://en.wiktionary.org/wiki/aquitard" class="extiw" title="wikt:aquitard">aquitard</a></i> is a zone within the Earth that restricts the flow of groundwater from one aquifer to another. An aquitard can sometimes, if completely impermeable, be called an <i>aquiclude</i> or <i>aquifuge</i>. Aquitards are composed of layers of either <a href="/wiki/Clay" title="Clay">clay</a> or non-porous rock with low <a href="/wiki/Hydraulic_conductivity" title="Hydraulic conductivity">hydraulic conductivity</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Saturated_versus_unsaturated">Saturated versus unsaturated</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=5" title="Edit section: Saturated versus unsaturated"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Water_content" title="Water content">Water content</a> and <a href="/wiki/Soil_moisture" title="Soil moisture">Soil moisture</a></div> <p>Groundwater can be found at nearly every point in the Earth's shallow subsurface to some degree, although aquifers do not necessarily contain <a href="/wiki/Fresh_water" title="Fresh water">fresh water</a>. The Earth's crust can be divided into two regions: the <i><a href="/wiki/Water_content" title="Water content">saturated</a> zone</i> or <i><a href="/wiki/Phreatic" title="Phreatic">phreatic</a> zone</i> (e.g., aquifers, aquitards, etc.), where all available spaces are filled with water, and the <i>unsaturated zone</i> (also called the <a href="/wiki/Vadose_zone" title="Vadose zone">vadose zone</a>), where there are still pockets of air that contain some water, but can be filled with more water. </p><p><i>Saturated</i> means the pressure head of the water is greater than <a href="/wiki/Atmospheric_pressure" title="Atmospheric pressure">atmospheric pressure</a> (it has a gauge pressure > 0). The definition of the water table is the surface where the <a href="/wiki/Hydraulic_head" title="Hydraulic head">pressure head</a> is equal to atmospheric pressure (where gauge pressure = 0). </p><p><i>Unsaturated</i> conditions occur above the water table where the pressure head is negative (absolute pressure can never be negative, but gauge pressure can) and the water that incompletely fills the pores of the aquifer material is under <a href="/wiki/Suction" title="Suction">suction</a>. The <a href="/wiki/Hydrogeology#Water_content" title="Hydrogeology">water content</a> in the unsaturated zone is held in place by surface <a href="/wiki/Adhesion" title="Adhesion">adhesive forces</a> and it rises above the water table (the zero-<a href="/wiki/Hydrogeology#Hydraulic_head" title="Hydrogeology">gauge-pressure</a> <a href="/wiki/Contour_line#Barometric_pressure" title="Contour line">isobar</a>) by <a href="/wiki/Capillary_action" title="Capillary action">capillary action</a> to saturate a small zone above the phreatic surface (the <a href="/wiki/Capillary_fringe" title="Capillary fringe">capillary fringe</a>) at less than atmospheric pressure. This is termed tension saturation and is not the same as saturation on a water-content basis. Water content in a capillary fringe decreases with increasing distance from the phreatic surface. The capillary head depends on soil pore size. In <a href="/wiki/Sand" title="Sand">sandy</a> soils with larger pores, the head will be less than in clay soils with very small pores. The normal capillary rise in a clayey soil is less than 1.8 m (6 ft) but can range between 0.3 and 10 m (1 and 33 ft).<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>The capillary rise of water in a small-<a href="/wiki/Diameter" title="Diameter">diameter</a> tube involves the same physical process. The water table is the level to which water will rise in a large-diameter pipe (e.g., a well) that goes down into the aquifer and is open to the atmosphere. </p> <div class="mw-heading mw-heading3"><h3 id="Aquifers_versus_aquitards">Aquifers versus aquitards</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=6" title="Edit section: Aquifers versus aquitards"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Aquifers are typically saturated regions of the subsurface that produce an economically feasible quantity of water to a well or <a href="/wiki/Spring_(hydrosphere)" class="mw-redirect" title="Spring (hydrosphere)">spring</a> (e.g., sand and <a href="/wiki/Gravel" title="Gravel">gravel</a> or fractured <a href="/wiki/Bedrock" title="Bedrock">bedrock</a> often make good aquifer materials). </p><p>An aquitard is a zone within the Earth that restricts the flow of groundwater from one aquifer to another.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> A completely impermeable aquitard is called an <i>aquiclude</i> or <i>aquifuge</i>. Aquitards contain layers of either clay or non-porous rock with low <a href="/wiki/Hydraulic_conductivity" title="Hydraulic conductivity">hydraulic conductivity</a>. </p><p>In mountainous areas (or near rivers in mountainous areas), the main aquifers are typically unconsolidated <a href="/wiki/Alluvium" title="Alluvium">alluvium</a>, composed of mostly horizontal layers of materials deposited by water processes (rivers and streams), which in cross-section (looking at a two-dimensional slice of the aquifer) appear to be layers of alternating coarse and fine materials. Coarse materials, because of the high energy needed to move them, tend to be found nearer the source (mountain fronts or rivers), whereas the fine-grained material will make it farther from the source (to the flatter parts of the basin or overbank areas—sometimes called the pressure area). Since there are less fine-grained deposits near the source, this is a place where aquifers are often unconfined (sometimes called the forebay area), or in hydraulic communication with the land surface. </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Hydraulic_conductivity" title="Hydraulic conductivity">Hydraulic conductivity</a> and <a href="/wiki/Storativity" class="mw-redirect" title="Storativity">Storativity</a></div> <div class="mw-heading mw-heading3"><h3 id="Confined_versus_unconfined">Confined versus unconfined</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=7" title="Edit section: Confined versus unconfined"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An unconfined aquifer has no impermeable barrier immediately above it, such that the water level can rise in response to recharge. A confined aquifer has an overlying impermeable barrier that prevents the water level in the aquifer from rising any higher. An aquifer in the same geologic unit may be confined in one area and unconfined in another. <i>Unconfined</i> aquifers are sometimes also called <i>water table</i> or <i>phreatic</i> aquifers, because their upper boundary is the <a href="/wiki/Water_table" title="Water table">water table</a> or phreatic surface (see <a href="/wiki/Biscayne_Aquifer" title="Biscayne Aquifer">Biscayne Aquifer</a>). Typically (but not always) the shallowest aquifer at a given location is unconfined, meaning it does not have a confining layer (an aquitard or aquiclude) between it and the surface. The term "perched" refers to ground water accumulating above a low-permeability unit or strata, such as a clay layer. This term is generally used to refer to a small local area of ground water that occurs at an elevation higher than a regionally extensive aquifer. The difference between perched and unconfined aquifers is their size (perched is smaller). Confined aquifers are aquifers that are overlain by a confining layer, often made up of clay. The confining layer might offer some protection from surface contamination. </p><p>If the distinction between confined and unconfined is not clear geologically (i.e., if it is not known if a clear confining layer exists, or if the geology is more complex, e.g., a fractured bedrock aquifer), the value of storativity returned from an <a href="/wiki/Aquifer_test" title="Aquifer test">aquifer test</a> can be used to determine it (although aquifer tests in unconfined aquifers should be interpreted differently than confined ones). Confined aquifers have very low <a href="/wiki/Specific_storage" title="Specific storage">storativity</a> values (much less than 0.01, and as little as 10<sup><span class="nowrap"><span data-sort-value="2999500000000000000♠"></span>−5</span></sup>), which means that the aquifer is storing water using the mechanisms of aquifer matrix expansion and the compressibility of water, which typically are both quite small quantities. Unconfined aquifers have storativities (typically called <a href="/wiki/Specific_storage" title="Specific storage">specific yield</a>) greater than 0.01 (1% of bulk volume); they release water from storage by the mechanism of actually draining the pores of the aquifer, releasing relatively large amounts of water (up to the drainable <a href="/wiki/Hydrogeology#Porosity" title="Hydrogeology">porosity</a> of the aquifer material, or the minimum volumetric <a href="/wiki/Water_content" title="Water content">water content</a>). </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Porosity" title="Porosity">Porosity</a> and <a href="/wiki/Storativity" class="mw-redirect" title="Storativity">Storativity</a></div> <div class="mw-heading mw-heading3"><h3 id="Isotropic_versus_anisotropic">Isotropic versus anisotropic</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=8" title="Edit section: Isotropic versus anisotropic"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In <a href="/wiki/Isotropy" title="Isotropy">isotropic</a> aquifers or aquifer layers the hydraulic conductivity (K) is equal for flow in all directions, while in <a href="/wiki/Anisotropy" title="Anisotropy">anisotropic</a> conditions it differs, notably in horizontal (Kh) and vertical (Kv) sense. </p><p>Semi-confined aquifers with one or more aquitards work as an anisotropic system, even when the separate layers are isotropic, because the compound Kh and Kv values are different (see <a href="/wiki/Transmissibility_(fluid)" class="mw-redirect" title="Transmissibility (fluid)">hydraulic transmissivity</a> and <a href="/wiki/Hydraulic_conductivity#Resistance" title="Hydraulic conductivity">hydraulic resistance</a>). </p><p>When calculating <a href="/wiki/Drainage_equation" title="Drainage equation">flow to drains</a><sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> or <a href="/wiki/Drainage_by_wells" class="mw-redirect" title="Drainage by wells">flow to wells</a><sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> in an aquifer, the anisotropy is to be taken into account lest the resulting design of the drainage system may be faulty. </p> <div class="mw-heading mw-heading3"><h3 id="Porous,_karst,_or_fractured"><span id="Porous.2C_karst.2C_or_fractured"></span>Porous, karst, or fractured</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=9" title="Edit section: Porous, karst, or fractured"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>To properly manage an aquifer its properties must be understood. Many properties must be known to predict how an aquifer will respond to rainfall, drought, pumping, and <a href="/wiki/Pollution#Definitions_and_types" title="Pollution">contamination</a>. Considerations include where and how much water enters the groundwater from rainfall and snowmelt, how fast and in what direction the groundwater travels, and how much water leaves the ground as springs. <a href="/wiki/Groundwater_model" title="Groundwater model">Computer models</a> can be used to test how accurately the understanding of the aquifer properties matches the actual aquifer performance.<sup id="cite_ref-FieldMethodsGeoHydrogeo_12-0" class="reference"><a href="#cite_note-FieldMethodsGeoHydrogeo-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 192–193, 233–237">: 192–193, 233–237 </span></sup> Environmental regulations require sites with potential sources of contamination to demonstrate that the <a href="/wiki/Hydrology#Groundwater" title="Hydrology">hydrology</a> has been <a href="/wiki/Environmental_monitoring" title="Environmental monitoring">characterized</a>.<sup id="cite_ref-FieldMethodsGeoHydrogeo_12-1" class="reference"><a href="#cite_note-FieldMethodsGeoHydrogeo-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 3">: 3 </span></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Porous">Porous</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=10" title="Edit section: Porous"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg" class="mw-file-description"><img alt="Water slowly seeping from tan porous sandstone at contact with impermeable gray shale creates a refreshing growth of green vegetation in the desert." src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg/220px-Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg/330px-Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg/440px-Water_seep_from_sandstone_in_Hanging_Garden_SE_Utah.jpg 2x" data-file-width="650" data-file-height="433" /></a><figcaption>Water in porous aquifers slowly seeps through pore spaces between sand grains</figcaption></figure> <p>Porous aquifers typically occur in sand and <a href="/wiki/Sandstone" title="Sandstone">sandstone</a>. Porous aquifer properties depend on the <a href="/wiki/Depositional_environment" title="Depositional environment">depositional sedimentary environment</a> and later natural cementation of the sand grains. The environment where a sand body was deposited controls the orientation of the sand grains, the horizontal and vertical variations, and the distribution of shale layers. Even thin shale layers are important barriers to groundwater flow. All these factors affect the <a href="/wiki/Porosity" title="Porosity">porosity</a> and <a href="/wiki/Permeability_(earth_sciences)" class="mw-redirect" title="Permeability (earth sciences)">permeability</a> of sandy aquifers.<sup id="cite_ref-SandSandstone_13-0" class="reference"><a href="#cite_note-SandSandstone-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 413">: 413 </span></sup> </p><p>Sandy deposits formed in <a href="/wiki/Shallow_water_marine_environment" title="Shallow water marine environment">shallow marine environments</a> and in <a href="/wiki/Aeolian_processes" title="Aeolian processes">windblown sand dune environments</a> have moderate to high permeability while sandy deposits formed in <a href="/wiki/Fluvial_processes" class="mw-redirect" title="Fluvial processes">river environments</a> have low to moderate permeability.<sup id="cite_ref-SandSandstone_13-1" class="reference"><a href="#cite_note-SandSandstone-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 418">: 418 </span></sup> Rainfall and snowmelt enter the groundwater where the aquifer is near the surface. Groundwater flow directions can be determined from <a href="/wiki/Potentiometric_surface" title="Potentiometric surface">potentiometric surface</a> maps of water levels in wells and springs. <a href="/wiki/Aquifer_test" title="Aquifer test">Aquifer tests</a> and <a href="/wiki/Well_test" title="Well test">well tests</a> can be used with <a href="/wiki/Darcy%27s_law" title="Darcy's law">Darcy's law</a> flow equations to determine the ability of a porous aquifer to convey water.<sup id="cite_ref-FieldMethodsGeoHydrogeo_12-2" class="reference"><a href="#cite_note-FieldMethodsGeoHydrogeo-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 177–184">: 177–184 </span></sup> </p><p>Analyzing this type of information over an area gives an indication how much water can be pumped without <a href="/wiki/Overdrafting" title="Overdrafting">overdrafting</a> and how contamination will travel.<sup id="cite_ref-FieldMethodsGeoHydrogeo_12-3" class="reference"><a href="#cite_note-FieldMethodsGeoHydrogeo-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 233">: 233 </span></sup> In porous aquifers groundwater flows as slow seepage in pores between sand grains. A groundwater flow rate of 1 foot per day (0.3 m/d) is considered to be a high rate for porous aquifers,<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> as illustrated by the water slowly seeping from sandstone in the accompanying image to the left. </p><p>Porosity is important, but, <i>alone</i>, it does not determine a rock's ability to act as an aquifer. Areas of the <a href="/wiki/Deccan_Traps" title="Deccan Traps">Deccan Traps</a> (a <a href="/wiki/Basalt" title="Basalt">basaltic</a> lava) in west central India are good examples of rock formations with high porosity but low permeability, which makes them poor aquifers. Similarly, the micro-porous (Upper <a href="/wiki/Cretaceous" title="Cretaceous">Cretaceous</a>) <a href="/wiki/Chalk_Group" title="Chalk Group">Chalk Group</a> of south east England, although having a reasonably high porosity, has a low grain-to-grain permeability, with its good water-yielding characteristics mostly due to micro-fracturing and fissuring. </p> <div class="mw-heading mw-heading4"><h4 id="Karst">Karst</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=11" title="Edit section: Karst"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:MammothCaveNPS.jpg" class="mw-file-description"><img alt="Several people in a jon boat on a river inside a cave." src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8b/MammothCaveNPS.jpg/220px-MammothCaveNPS.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8b/MammothCaveNPS.jpg/330px-MammothCaveNPS.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8b/MammothCaveNPS.jpg/440px-MammothCaveNPS.jpg 2x" data-file-width="516" data-file-height="387" /></a><figcaption>Water in karst aquifers can form <a href="/wiki/Subterranean_river" title="Subterranean river">subterranean rivers</a>.</figcaption></figure> <p><a href="/wiki/Karst" title="Karst">Karst</a> aquifers typically develop in <a href="/wiki/Limestone" title="Limestone">limestone</a>. Surface water containing natural <a href="/wiki/Carbonic_acid" title="Carbonic acid">carbonic acid</a> moves down into small fissures in limestone. This carbonic acid gradually dissolves limestone thereby enlarging the fissures. The enlarged fissures allow a larger quantity of water to enter which leads to a progressive enlargement of openings. Abundant small openings store a large quantity of water. The larger openings form a conduit system that drains the aquifer to springs.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>Characterization of karst aquifers requires field exploration to locate <a href="/wiki/Sinkhole" title="Sinkhole">sinkholes, swallets</a>, <a href="/wiki/Losing_stream" title="Losing stream">sinking streams</a>, and <a href="/wiki/Spring_(hydrology)" title="Spring (hydrology)">springs</a> in addition to studying <a href="/wiki/Geologic_map" title="Geologic map">geologic maps</a>.<sup id="cite_ref-DelineationGrdwtrBasinsTaylor_16-0" class="reference"><a href="#cite_note-DelineationGrdwtrBasinsTaylor-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 4">: 4 </span></sup> Conventional hydrogeologic methods such as aquifer tests and potentiometric mapping are insufficient to characterize the complexity of karst aquifers. These conventional investigation methods need to be supplemented with <a href="/wiki/Dye_tracing" title="Dye tracing">dye traces</a>, measurement of spring discharges, and analysis of water chemistry.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> U.S. Geological Survey dye tracing has determined that conventional groundwater models that assume a uniform distribution of porosity are not applicable for karst aquifers.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p><p>Linear alignment of surface features such as straight stream segments and sinkholes develop along <a href="/wiki/Fracture_(geology)" title="Fracture (geology)">fracture traces</a>. Locating a well in a fracture trace or intersection of fracture traces increases the likelihood to encounter good water production.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> Voids in karst aquifers can be large enough to cause destructive collapse or <a href="/wiki/Subsidence" title="Subsidence">subsidence</a> of the ground surface that can initiate a catastrophic release of contaminants.<sup id="cite_ref-FieldMethodsGeoHydrogeo_12-4" class="reference"><a href="#cite_note-FieldMethodsGeoHydrogeo-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 3–4">: 3–4 </span></sup> Groundwater flow rate in karst aquifers is much more rapid than in porous aquifers as shown in the accompanying image to the left. For example, in the Barton Springs Edwards aquifer, dye traces measured the karst groundwater flow rates from 0.5 to 7 miles per day (0.8 to 11.3 km/d).<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> The rapid groundwater flow rates make <a href="/wiki/Karst#Hydrology" title="Karst">karst aquifers much more sensitive</a> to groundwater contamination than porous aquifers.<sup id="cite_ref-DelineationGrdwtrBasinsTaylor_16-1" class="reference"><a href="#cite_note-DelineationGrdwtrBasinsTaylor-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 1">: 1 </span></sup> </p><p>In the extreme case, groundwater may exist in <i>underground rivers</i> (e.g., <a href="/wiki/Cave" title="Cave">caves</a> underlying <a href="/wiki/Karst_topography" class="mw-redirect" title="Karst topography">karst topography</a>. </p> <div class="mw-heading mw-heading4"><h4 id="Fractured">Fractured</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=12" title="Edit section: Fractured"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>If a rock unit of low <a href="/wiki/Porosity" title="Porosity">porosity</a> is highly fractured, it can also make a good aquifer (via <a href="/wiki/Fracture_(geology)" title="Fracture (geology)">fissure</a> flow), provided the rock has a hydraulic conductivity sufficient to facilitate movement of water. </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Major_US_Aquifers_by_Rock_Type.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Major_US_Aquifers_by_Rock_Type.jpg/220px-Major_US_Aquifers_by_Rock_Type.jpg" decoding="async" width="220" height="170" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Major_US_Aquifers_by_Rock_Type.jpg/330px-Major_US_Aquifers_by_Rock_Type.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Major_US_Aquifers_by_Rock_Type.jpg/440px-Major_US_Aquifers_by_Rock_Type.jpg 2x" data-file-width="1056" data-file-height="816" /></a><figcaption>Map of major US aquifers by rock type</figcaption></figure> <div class="mw-heading mw-heading2"><h2 id="Human_use_of_groundwater">Human use of groundwater</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=13" title="Edit section: Human use of groundwater"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/Groundwater#Challenges" title="Groundwater">Groundwater § Challenges</a></div> <div class="excerpt-block"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1066933788"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable dablink excerpt-hat selfref">This section is an excerpt from <a href="/wiki/Groundwater#Uses_by_humans" title="Groundwater">Groundwater § Uses by humans</a>.<span class="mw-editsection-like plainlinks"><span class="mw-editsection-bracket">[</span><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Groundwater&action=edit#Uses_by_humans">edit</a><span class="mw-editsection-bracket">]</span></span></div><div class="excerpt"> Reliance on groundwater will only increase, mainly due to growing water demand by all sectors combined with <a href="/wiki/Effects_of_climate_change_on_the_water_cycle" title="Effects of climate change on the water cycle">increasing variation in rainfall patterns</a>.<sup id="cite_ref-Groundwater_WWDR2022_21-0" class="reference"><a href="#cite_note-Groundwater_WWDR2022-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup></div></div> <p>Challenges for using groundwater include: <a href="/wiki/Overdrafting" title="Overdrafting">overdrafting</a> (extracting groundwater beyond the <a href="/wiki/Dynamic_equilibrium" title="Dynamic equilibrium">equilibrium</a> yield of the aquifer), <a href="/wiki/Groundwater-related_subsidence" title="Groundwater-related subsidence">groundwater-related subsidence</a> of land, groundwater becoming saline, <a href="/wiki/Groundwater_pollution" title="Groundwater pollution">groundwater pollution</a>. </p> <div class="mw-heading mw-heading2"><h2 id="By_country_or_continent">By country or continent</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=14" title="Edit section: By country or continent"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="/wiki/List_of_aquifers" title="List of aquifers">List of aquifers</a> and <a href="/wiki/Aquifers_in_the_United_States" class="mw-redirect" title="Aquifers in the United States">Aquifers in the United States</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Texas_blind_salamander.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Texas_blind_salamander.jpg/220px-Texas_blind_salamander.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Texas_blind_salamander.jpg/330px-Texas_blind_salamander.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Texas_blind_salamander.jpg/440px-Texas_blind_salamander.jpg 2x" data-file-width="488" data-file-height="366" /></a><figcaption><a href="/wiki/Texas_blind_salamander" title="Texas blind salamander">Texas blind salamander</a> found in <a href="/wiki/Edwards_Aquifer" title="Edwards Aquifer">Edwards Aquifer</a></figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Africa">Africa</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=15" title="Edit section: Africa"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Aquifer depletion is a problem in some areas, especially in northern <a href="/wiki/Africa" title="Africa">Africa</a>, where one example is the <a href="/wiki/Great_Manmade_River" class="mw-redirect" title="Great Manmade River">Great Manmade River</a> project of <a href="/wiki/Libya" title="Libya">Libya</a>. However, new methods of groundwater management such as artificial recharge and injection of surface waters during seasonal wet periods has extended the life of many freshwater aquifers, especially in the United States. </p> <div class="mw-heading mw-heading3"><h3 id="Australia">Australia</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=16" title="Edit section: Australia"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Great_Artesian_Basin" title="Great Artesian Basin">Great Artesian Basin</a> situated in <a href="/wiki/Australia" title="Australia">Australia</a> is arguably the largest groundwater aquifer in the world<sup id="cite_ref-qldgovt_22-0" class="reference"><a href="#cite_note-qldgovt-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> (over 1.7 million km<sup>2</sup> or 0.66 million sq mi). It plays a large part in water supplies for Queensland, and some remote parts of South Australia. </p> <div class="mw-heading mw-heading3"><h3 id="Canada">Canada</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=17" title="Edit section: Canada"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Discontinuous sand bodies at the base of the <a href="/wiki/McMurray_Formation" title="McMurray Formation">McMurray Formation</a> in the <a href="/wiki/Athabasca_Oil_Sands" class="mw-redirect" title="Athabasca Oil Sands">Athabasca Oil Sands</a> region of northeastern <a href="/wiki/Alberta" title="Alberta">Alberta</a>, Canada, are commonly referred to as the <a href="/wiki/McMurray_Formation#Hydrogeology" title="McMurray Formation">Basal Water Sand (BWS) aquifers</a>.<sup id="cite_ref-Total2005_23-0" class="reference"><a href="#cite_note-Total2005-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> Saturated with water, they are confined beneath impermeable <a href="/wiki/Bitumen" title="Bitumen">bitumen</a>-saturated sands that are exploited to recover bitumen for <a href="/wiki/Synthetic_crude" title="Synthetic crude">synthetic crude</a> oil production. Where they are deep-lying and recharge occurs from underlying <a href="/wiki/Devonian" title="Devonian">Devonian</a> <a href="/wiki/Formation_(geology)" class="mw-redirect" title="Formation (geology)">formations</a> they are saline, and where they are shallow and recharged by <a href="/wiki/Meteoric_water" title="Meteoric water">surface water</a> they are non-saline. The BWS typically pose problems for the recovery of bitumen, whether by <a href="/wiki/Open-pit_mining" title="Open-pit mining">open-pit mining</a> or by <i>in situ</i> methods such as <a href="/wiki/Steam-assisted_gravity_drainage" title="Steam-assisted gravity drainage">steam-assisted gravity drainage</a> (SAGD), and in some areas they are targets for waste-water injection.<sup id="cite_ref-Barson_24-0" class="reference"><a href="#cite_note-Barson-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Pembina_25-0" class="reference"><a href="#cite_note-Pembina-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FMFNtoCEAAJun2012_26-0" class="reference"><a href="#cite_note-FMFNtoCEAAJun2012-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="South_America">South America</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=18" title="Edit section: South America"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Guarani_Aquifer" title="Guarani Aquifer">Guarani Aquifer</a>, located beneath the surface of <a href="/wiki/Argentina" title="Argentina">Argentina</a>, <a href="/wiki/Brazil" title="Brazil">Brazil</a>, <a href="/wiki/Paraguay" title="Paraguay">Paraguay</a>, and <a href="/wiki/Uruguay" title="Uruguay">Uruguay</a>, is one of the world's largest aquifer systems and is an important source of <a href="/wiki/Fresh_water" title="Fresh water">fresh water</a>.<sup id="cite_ref-Science_and_Diplomacy._27-0" class="reference"><a href="#cite_note-Science_and_Diplomacy.-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> Named after the <a href="/wiki/Guaran%C3%AD_people" title="Guaraní people">Guarani people</a>, it covers 1,200,000 km<sup>2</sup> (460,000 sq mi), with a volume of about 40,000 km<sup>3</sup> (9,600 cu mi), a thickness of between 50 and 800 m (160 and 2,620 ft) and a maximum depth of about 1,800 m (5,900 ft). </p> <div class="mw-heading mw-heading3"><h3 id="United_States">United States</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=19" title="Edit section: United States"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Ogallala_Aquifer" title="Ogallala Aquifer">Ogallala Aquifer</a> of the central United States is one of the world's great aquifers, but in places it is being rapidly <a href="/wiki/Overdrafting" title="Overdrafting">depleted</a> by growing municipal use, and continuing agricultural use. This huge aquifer, which underlies portions of eight states, contains primarily <a href="/wiki/Fossil_water" title="Fossil water">fossil water</a> from the time of the last <a href="/wiki/Quaternary_glaciation" title="Quaternary glaciation">glaciation</a>. Annual recharge, in the more arid parts of the aquifer, is estimated to total only about 10 percent of annual withdrawals. According to a 2013 report by the <a href="/wiki/United_States_Geological_Survey" title="United States Geological Survey">United States Geological Survey</a> (USGS), the depletion between 2001 and 2008, inclusive, is about 32 percent of the cumulative depletion during the entire 20th century.<sup id="cite_ref-KonikowUSGSjan2013_28-0" class="reference"><a href="#cite_note-KonikowUSGSjan2013-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p><p>In the United States, the biggest users of water from aquifers include agricultural irrigation and oil and coal extraction.<sup id="cite_ref-depletion_29-0" class="reference"><a href="#cite_note-depletion-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> "Cumulative total groundwater depletion in the United States accelerated in the late 1940s and continued at an almost steady linear rate through the end of the century. In addition to widely recognized environmental consequences, groundwater depletion also adversely impacts the long-term sustainability of groundwater supplies to help meet the Nation’s water needs."<sup id="cite_ref-KonikowUSGSjan2013_28-1" class="reference"><a href="#cite_note-KonikowUSGSjan2013-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p><p>An example of a significant and sustainable carbonate aquifer is the <a href="/wiki/Edwards_Aquifer" title="Edwards Aquifer">Edwards Aquifer</a><sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> in central <a href="/wiki/Texas" title="Texas">Texas</a>. This carbonate aquifer has historically been providing high quality water for nearly 2 million people, and even today, is full because of tremendous recharge from a number of area streams, rivers and <a href="/wiki/Lake" title="Lake">lakes</a>. The primary risk to this resource is human development over the recharge areas. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=20" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Aquifer_storage_and_recovery" title="Aquifer storage and recovery">Aquifer storage and recovery</a> – Injection of water into an aquifer for later use</li> <li><a href="/wiki/Aquifer_Susceptibility" class="mw-redirect" title="Aquifer Susceptibility">Aquifer Susceptibility</a> – Ability of permeable rock to hold liquids<span style="display:none" class="category-annotation-with-redirected-description">Pages displaying short descriptions of redirect targets</span></li> <li><a href="/wiki/Artesian_aquifer" class="mw-redirect" title="Artesian aquifer">Artesian aquifer</a> – Confined aquifer containing groundwater under positive pressure<span style="display:none" class="category-annotation-with-redirected-description">Pages displaying short descriptions of redirect targets</span></li> <li><a href="/wiki/Catchment_hydrology" title="Catchment hydrology">Catchment hydrology</a> – Hydrology of drainage basins</li> <li><a href="/wiki/Hydraulic_tomography" title="Hydraulic tomography">Hydraulic tomography</a> – Use of multiple hydraulic tests to characterize an aquifer</li> <li><a href="/wiki/Overexploitation" title="Overexploitation">Overexploitation</a> – Depleting a renewable resource</li> <li><a href="/wiki/Seasonal_thermal_energy_storage" title="Seasonal thermal energy storage">Seasonal thermal energy storage</a> – Storage of heat or cold for periods of up to several months</li> <li><a href="/wiki/Spring_(hydrology)" title="Spring (hydrology)">Spring (hydrology)</a> – Point at which water emerges from an aquifer to the surface</li> <li><a href="/wiki/Surficial_aquifer" title="Surficial aquifer">Surficial aquifer</a> – Shallow, thin aquifer</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=21" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFWalker2022" class="citation journal cs1">Walker, Kira (2022). <a rel="nofollow" class="external text" href="https://www.natureasia.com/en/nmiddleeast/article/10.1038/nmiddleeast.2022.72">"Ancient systems keep water flowing"</a>. <i>Nature Middle East</i>. Nature. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1038%2Fnmiddleeast.2022.72">10.1038/nmiddleeast.2022.72</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:253486495">253486495</a><span class="reference-accessdate">. Retrieved <span class="nowrap">10 July</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature+Middle+East&rft.atitle=Ancient+systems+keep+water+flowing&rft.date=2022&rft_id=info%3Adoi%2F10.1038%2Fnmiddleeast.2022.72&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A253486495%23id-name%3DS2CID&rft.aulast=Walker&rft.aufirst=Kira&rft_id=https%3A%2F%2Fwww.natureasia.com%2Fen%2Fnmiddleeast%2Farticle%2F10.1038%2Fnmiddleeast.2022.72&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.usgs.gov/special-topic/water-science-school/science/aquifers-and-groundwater">"Aquifers and Groundwater"</a>. <i>USGS</i>. <q>...more than 30,000 feet. On average, however, the porosity and permeability of rocks decrease as their depth below land surface increases; the pores and cracks in rocks at great depths are closed or greatly reduced in size because of the weight of overlying rocks.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=USGS&rft.atitle=Aquifers+and+Groundwater&rft_id=https%3A%2F%2Fwww.usgs.gov%2Fspecial-topic%2Fwater-science-school%2Fscience%2Faquifers-and-groundwater&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.nationalgeographic.org/encyclopedia/aquifers/">"Aquifers"</a>. <i>National Geographic Society</i>. 2019-07-30<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-09-17</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=National+Geographic+Society&rft.atitle=Aquifers&rft.date=2019-07-30&rft_id=http%3A%2F%2Fwww.nationalgeographic.org%2Fencyclopedia%2Faquifers%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://ebooks.inflibnet.ac.in/geop16/chapter/types-of-aquifers-aquiclude-aquitard-and-aquifuge-and-location-of-aquifers/">"Types of aquifers: Aquiclude, Aquitard and Aquifuge and location of aquifers – Geography of Water Resources"</a>. <i>ebooks.inflibnet.ac.in</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-06-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=ebooks.inflibnet.ac.in&rft.atitle=Types+of+aquifers%3A+Aquiclude%2C+Aquitard+and+Aquifuge+and+location+of+aquifers+%E2%80%93+Geography+of+Water+Resources&rft_id=https%3A%2F%2Febooks.inflibnet.ac.in%2Fgeop16%2Fchapter%2Ftypes-of-aquifers-aquiclude-aquitard-and-aquifuge-and-location-of-aquifers%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.gizmag.com/freshwater-reserves-under-sea/30072/">"Huge reserves of freshwater lie beneath the ocean floor"</a>. Gizmag.com. 11 December 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">15 December</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Huge+reserves+of+freshwater+lie+beneath+the+ocean+floor&rft.pub=Gizmag.com&rft.date=2013-12-11&rft_id=http%3A%2F%2Fwww.gizmag.com%2Ffreshwater-reserves-under-sea%2F30072%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPostGroenKooiPerson2013" class="citation journal cs1">Post, V. E. A.; Groen, J.; Kooi, H.; Person, M.; Ge, S.; Edmunds, W. M. (2013). "Offshore fresh groundwater reserves as a global phenomenon". <i>Nature</i>. <b>504</b> (7478): 71–78. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2013Natur.504...71P">2013Natur.504...71P</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1038%2Fnature12858">10.1038/nature12858</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/24305150">24305150</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:4468578">4468578</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature&rft.atitle=Offshore+fresh+groundwater+reserves+as+a+global+phenomenon&rft.volume=504&rft.issue=7478&rft.pages=71-78&rft.date=2013&rft_id=info%3Adoi%2F10.1038%2Fnature12858&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A4468578%23id-name%3DS2CID&rft_id=info%3Apmid%2F24305150&rft_id=info%3Abibcode%2F2013Natur.504...71P&rft.aulast=Post&rft.aufirst=V.+E.+A.&rft.au=Groen%2C+J.&rft.au=Kooi%2C+H.&rft.au=Person%2C+M.&rft.au=Ge%2C+S.&rft.au=Edmunds%2C+W.+M.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFreezeCherry1979" class="citation book cs1">Freeze, R.A.; Cherry, J.A. (1979). <a rel="nofollow" class="external text" href="https://archive.org/details/groundwater00free"><i>Groundwater</i></a>. Prentice-Hall. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-13-365312-0" title="Special:BookSources/978-0-13-365312-0"><bdi>978-0-13-365312-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/643719314">643719314</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Groundwater&rft.pub=Prentice-Hall&rft.date=1979&rft_id=info%3Aoclcnum%2F643719314&rft.isbn=978-0-13-365312-0&rft.aulast=Freeze&rft.aufirst=R.A.&rft.au=Cherry%2C+J.A.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fgroundwater00free&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span> Accessed from: <a rel="nofollow" class="external free" href="http://hydrogeologistswithoutborders.org/wordpress/1979-english/">http://hydrogeologistswithoutborders.org/wordpress/1979-english/</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200406061947/http://hydrogeologistswithoutborders.org/wordpress/1979-english/">Archived</a> 2020-04-06 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20100809084433/http://www.ces.ncsu.edu/plymouth/programs/vepras.html">"Morphological Features of Soil Wetness"</a>. Ces.ncsu.edu. Archived from <a rel="nofollow" class="external text" href="http://www.ces.ncsu.edu/plymouth/programs/vepras.html">the original</a> on 9 August 2010<span class="reference-accessdate">. Retrieved <span class="nowrap">6 September</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Morphological+Features+of+Soil+Wetness&rft.pub=Ces.ncsu.edu&rft_id=http%3A%2F%2Fwww.ces.ncsu.edu%2Fplymouth%2Fprograms%2Fvepras.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.connectedwaters.unsw.edu.au/schools-resources/fact-sheets/understanding-aquitards-and-aquicludes">"Understanding Aquitards and Aquicludes | UNSW Connected Waters Initiative"</a>. <i>www.connectedwaters.unsw.edu.au</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2022-12-07</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.connectedwaters.unsw.edu.au&rft.atitle=Understanding+Aquitards+and+Aquicludes+%7C+UNSW+Connected+Waters+Initiative&rft_id=https%3A%2F%2Fwww.connectedwaters.unsw.edu.au%2Fschools-resources%2Ffact-sheets%2Funderstanding-aquitards-and-aquicludes&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><i>The energy balance of groundwater flow applied to subsurface drainage in anisotropic soils by pipes or ditches with entrance resistance</i>. International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. On line : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/pdf/enerart.pdf">[1]</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20090219221547/http://waterlog.info/pdf/enerart.pdf">Archived</a> 2009-02-19 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> . Paper based on: R.J. Oosterbaan, J. Boonstra and K.V.G.K. Rao, 1996, "The energy balance of groundwater flow". Published in V.P.Singh and B.Kumar (eds.), Subsurface-Water Hydrology, pp. 153–60, Vol. 2 of Proceedings of the International Conference on Hydrology and Water Resources, New Delhi, India, 1993. Kluwer Academic Publishers, Dordrecht, The Netherlands. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-7923-3651-8" title="Special:BookSources/978-0-7923-3651-8">978-0-7923-3651-8</a> . On line : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/pdf/enerbal.pdf">[2]</a> . The corresponding "EnDrain" software can be downloaded from : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/software.htm">[3]</a>, or from : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/endrain.htm">[4]</a></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text">ILRI (2000), <i>Subsurface drainage by (tube)wells: Well spacing equations for fully and partially penetrating wells in uniform or layered aquifers with or without anisotropy and entrance resistance</i>, 9 pp. Principles used in the "WellDrain" model. International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. On line : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/pdf/wellspac.pdf">[5]</a> . Download "WellDrain" software from : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/software.htm">[6]</a>, or from : <a rel="nofollow" class="external autonumber" href="http://www.waterlog.info/weldrain.htm">[7]</a></span> </li> <li id="cite_note-FieldMethodsGeoHydrogeo-12"><span class="mw-cite-backlink">^ <a href="#cite_ref-FieldMethodsGeoHydrogeo_12-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FieldMethodsGeoHydrogeo_12-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FieldMethodsGeoHydrogeo_12-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FieldMethodsGeoHydrogeo_12-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-FieldMethodsGeoHydrogeo_12-4"><sup><i><b>e</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAssaadLaMoreauxHughes2004" class="citation book cs1">Assaad, Fakhry; LaMoreaux, Philip; Hughes, Travis (2004). <i>Field methods for geologists and hydrogeologists</i>. Berlin, Germany: Springer-Verlag Berlin Heidelberg. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-662-05438-3">10.1007/978-3-662-05438-3</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3-540-40882-6" title="Special:BookSources/978-3-540-40882-6"><bdi>978-3-540-40882-6</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Field+methods+for+geologists+and+hydrogeologists&rft.place=Berlin%2C+Germany&rft.pub=Springer-Verlag+Berlin+Heidelberg&rft.date=2004&rft_id=info%3Adoi%2F10.1007%2F978-3-662-05438-3&rft.isbn=978-3-540-40882-6&rft.aulast=Assaad&rft.aufirst=Fakhry&rft.au=LaMoreaux%2C+Philip&rft.au=Hughes%2C+Travis&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-SandSandstone-13"><span class="mw-cite-backlink">^ <a href="#cite_ref-SandSandstone_13-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-SandSandstone_13-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPettijohnPotterSiever1987" class="citation book cs1">Pettijohn, Francis; Potter, Paul; Siever, Raymond (1987). <i>Sand and Sandstone</i>. New York: Springer Science+Business Media. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-1-4612-1066-5">10.1007/978-1-4612-1066-5</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-387-96350-1" title="Special:BookSources/978-0-387-96350-1"><bdi>978-0-387-96350-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Sand+and+Sandstone&rft.place=New+York&rft.pub=Springer+Science%2BBusiness+Media&rft.date=1987&rft_id=info%3Adoi%2F10.1007%2F978-1-4612-1066-5&rft.isbn=978-0-387-96350-1&rft.aulast=Pettijohn&rft.aufirst=Francis&rft.au=Potter%2C+Paul&rft.au=Siever%2C+Raymond&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAlleyReillyFranke1999" class="citation book cs1">Alley, William; Reilly, Thomas; Franke, O. (1999). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/sustainabilityof00alle/page/8"><i>Sustainability of ground-water resources</i></a></span>. Circular 1186. Denver, Colorado: U.S. Geological Survey. p. <a rel="nofollow" class="external text" href="https://archive.org/details/sustainabilityof00alle/page/8">8</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.3133%2Fcir1186">10.3133/cir1186</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-607-93040-5" title="Special:BookSources/978-0-607-93040-5"><bdi>978-0-607-93040-5</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Sustainability+of+ground-water+resources.&rft.place=Denver%2C+Colorado&rft.series=Circular+1186&rft.pages=8&rft.pub=U.S.+Geological+Survey&rft.date=1999&rft_id=info%3Adoi%2F10.3133%2Fcir1186&rft.isbn=978-0-607-93040-5&rft.aulast=Alley&rft.aufirst=William&rft.au=Reilly%2C+Thomas&rft.au=Franke%2C+O.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fsustainabilityof00alle%2Fpage%2F8&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDreybrodt1988" class="citation book cs1">Dreybrodt, Wolfgang (1988). <i>Processes in karst systems: physics, chemistry, and geology</i>. Springer Series in Physical Environment. Vol. 4. Berlin: Springer. pp. 2–3. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-642-83352-6">10.1007/978-3-642-83352-6</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3-642-83354-0" title="Special:BookSources/978-3-642-83354-0"><bdi>978-3-642-83354-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Processes+in+karst+systems%3A+physics%2C+chemistry%2C+and+geology&rft.place=Berlin&rft.series=Springer+Series+in+Physical+Environment&rft.pages=2-3&rft.pub=Springer&rft.date=1988&rft_id=info%3Adoi%2F10.1007%2F978-3-642-83352-6&rft.isbn=978-3-642-83354-0&rft.aulast=Dreybrodt&rft.aufirst=Wolfgang&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-DelineationGrdwtrBasinsTaylor-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-DelineationGrdwtrBasinsTaylor_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-DelineationGrdwtrBasinsTaylor_16-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTaylor1997" class="citation book cs1">Taylor, Charles (1997). <a rel="nofollow" class="external text" href="https://pubs.usgs.gov/wri/1996/4254/report.pdf"><i>Delineation of ground-water basins and recharge areas for municipal water-supply springs in a karst aquifer system in the Elizabethtown area, Northern Kentucky</i></a> <span class="cs1-format">(PDF)</span>. Water-Resources Investigations Report 96-4254. Denver, Colorado: U.S. Geological Survey. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.3133%2Fwri964254">10.3133/wri964254</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Delineation+of+ground-water+basins+and+recharge+areas+for+municipal+water-supply+springs+in+a+karst+aquifer+system+in+the+Elizabethtown+area%2C+Northern+Kentucky&rft.place=Denver%2C+Colorado&rft.series=Water-Resources+Investigations+Report+96-4254&rft.pub=U.S.+Geological+Survey&rft.date=1997&rft_id=info%3Adoi%2F10.3133%2Fwri964254&rft.aulast=Taylor&rft.aufirst=Charles&rft_id=https%3A%2F%2Fpubs.usgs.gov%2Fwri%2F1996%2F4254%2Freport.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTaylorGreene2008" class="citation book cs1">Taylor, Charles; Greene, Earl (2008). <a rel="nofollow" class="external text" href="https://pubs.usgs.gov/tm/04d02/pdf/TM4-D2-chap3.pdf">"Hydrogeologic characterization and methods used in the investigation of karst hydrology."</a> <span class="cs1-format">(PDF)</span>. <i>Field Techniques for Estimating Water Fluxes Between Surface Water and Ground Water</i>. Techniques and Methods 4–D2. U.S. Geological Survey. p. 107. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20081102202902/http://pubs.usgs.gov/tm/04d02/pdf/TM4-D2-chap3.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2008-11-02.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Hydrogeologic+characterization+and+methods+used+in+the+investigation+of+karst+hydrology.&rft.btitle=Field+Techniques+for+Estimating+Water+Fluxes+Between+Surface+Water+and+Ground+Water&rft.series=Techniques+and+Methods+4%E2%80%93D2&rft.pages=107&rft.pub=U.S.+Geological+Survey&rft.date=2008&rft.aulast=Taylor&rft.aufirst=Charles&rft.au=Greene%2C+Earl&rft_id=https%3A%2F%2Fpubs.usgs.gov%2Ftm%2F04d02%2Fpdf%2FTM4-D2-chap3.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRenkenCunninghamZygnerskiWacker2005" class="citation journal cs1">Renken, R.; Cunningham, K.; Zygnerski, M.; Wacker, M.; Shapiro, A.; Harvey, R.; Metge, D.; Osborn, C.; Ryan, J. (November 2005). "Assessing the Vulnerability of a Municipal Well Field to Contamination in a Karst Aquifer". <i>Environmental and Engineering Geoscience</i>. <b>11</b> (4). GeoScienceWorld: 320. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2005EEGeo..11..319R">2005EEGeo..11..319R</a>. <a href="/wiki/CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.372.1559">10.1.1.372.1559</a></span>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.2113%2F11.4.319">10.2113/11.4.319</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Environmental+and+Engineering+Geoscience&rft.atitle=Assessing+the+Vulnerability+of+a+Municipal+Well+Field+to+Contamination+in+a+Karst+Aquifer&rft.volume=11&rft.issue=4&rft.pages=320&rft.date=2005-11&rft_id=https%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fsummary%3Fdoi%3D10.1.1.372.1559%23id-name%3DCiteSeerX&rft_id=info%3Adoi%2F10.2113%2F11.4.319&rft_id=info%3Abibcode%2F2005EEGeo..11..319R&rft.aulast=Renken&rft.aufirst=R.&rft.au=Cunningham%2C+K.&rft.au=Zygnerski%2C+M.&rft.au=Wacker%2C+M.&rft.au=Shapiro%2C+A.&rft.au=Harvey%2C+R.&rft.au=Metge%2C+D.&rft.au=Osborn%2C+C.&rft.au=Ryan%2C+J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFetter1988" class="citation book cs1">Fetter, Charles (1988). <i>Applied Hydrology</i>. Columbus, Ohio: Merrill. pp. 294–295. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-675-20887-1" title="Special:BookSources/978-0-675-20887-1"><bdi>978-0-675-20887-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Applied+Hydrology&rft.place=Columbus%2C+Ohio&rft.pages=294-295&rft.pub=Merrill&rft.date=1988&rft.isbn=978-0-675-20887-1&rft.aulast=Fetter&rft.aufirst=Charles&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFScanlonMaceBarrettSmith2003" class="citation journal cs1"><a href="/wiki/Bridget_Scanlon" title="Bridget Scanlon">Scanlon, Bridget</a>; Mace, Robert; Barrett, Michael; Smith, Brian (2003). "Can we simulate regional groundwater flow in a karst system using equivalent porous media models? Case study, Barton Springs Edwards aquifer, USA". <i>Journal of Hydrology</i>. <b>276</b> (1–4). Elsevier Science: 142. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2003JHyd..276..137S">2003JHyd..276..137S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0022-1694%2803%2900064-7">10.1016/S0022-1694(03)00064-7</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:16046040">16046040</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Hydrology&rft.atitle=Can+we+simulate+regional+groundwater+flow+in+a+karst+system+using+equivalent+porous+media+models%3F+Case+study%2C+Barton+Springs+Edwards+aquifer%2C+USA&rft.volume=276&rft.issue=1%E2%80%934&rft.pages=142&rft.date=2003&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A16046040%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1016%2FS0022-1694%2803%2900064-7&rft_id=info%3Abibcode%2F2003JHyd..276..137S&rft.aulast=Scanlon&rft.aufirst=Bridget&rft.au=Mace%2C+Robert&rft.au=Barrett%2C+Michael&rft.au=Smith%2C+Brian&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-Groundwater_WWDR2022-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-Groundwater_WWDR2022_21-0">^</a></b></span> <span class="reference-text">United Nations (2022) <a rel="nofollow" class="external text" href="https://unesdoc.unesco.org/ark:/48223/pf0000380721">The United Nations World Water Development Report 2022: Groundwater: Making the invisible visible</a>. UNESCO, Paris Text was copied from this source, which is available under a <a href="//creativecommons.org/licenses/by/3.0/" class="extiw" title="creativecommons:by/3.0/">Creative Commons Attribution 3.0 International License</a></span> </li> <li id="cite_note-qldgovt-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-qldgovt_22-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20061113031749/http://www.nrw.qld.gov.au/factsheets/pdf/water/w68.pdf">"The Great Artesian Basin"</a> <span class="cs1-format">(PDF)</span>. <i>Facts: Water Series</i>. Queensland Department of Natural Resources and Water. Archived from <a rel="nofollow" class="external text" href="http://www.nrw.qld.gov.au/factsheets/pdf/water/w68.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 13 November 2006<span class="reference-accessdate">. Retrieved <span class="nowrap">3 January</span> 2007</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Facts%3A+Water+Series&rft.atitle=The+Great+Artesian+Basin&rft_id=http%3A%2F%2Fwww.nrw.qld.gov.au%2Ffactsheets%2Fpdf%2Fwater%2Fw68.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-Total2005-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-Total2005_23-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation report cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20131202222021/http://www.total-ep-canada.com/upstream/documents/application/CR_4_Groundwater_Report.pdf">Joslyn North Mine Project: Environmental Impact Assessment Hydrologeology</a> <span class="cs1-format">(PDF)</span> (Report). <a href="/wiki/Edmonton" title="Edmonton">Edmonton</a>, Alberta: Deer Creek Energy. December 2005. p. 4. Archived from <a rel="nofollow" class="external text" href="http://www.total-ep-canada.com/upstream/documents/application/CR_4_Groundwater_Report.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2 December 2013.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Joslyn+North+Mine+Project%3A+Environmental+Impact+Assessment+Hydrologeology&rft.place=Edmonton%2C+Alberta&rft.pages=4&rft.pub=Deer+Creek+Energy&rft.date=2005-12&rft_id=http%3A%2F%2Fwww.total-ep-canada.com%2Fupstream%2Fdocuments%2Fapplication%2FCR_4_Groundwater_Report.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-Barson-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-Barson_24-0">^</a></b></span> <span class="reference-text">Barson, D., Bachu, S. and Esslinger, P. 2001. Flow systems in the Mannville Group in the east-central Athabasca area and implications for steam-assisted gravity drainage (SAGD) operations for in situ bitumen production. Bulletin of Canadian Petroleum Geology, vol. 49, no. 3, pp. 376–92.</span> </li> <li id="cite_note-Pembina-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-Pembina_25-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGriffithsWoynillowicz2003" class="citation report cs1">Griffiths, Mary; Woynillowicz, Dan (April 2003). <a rel="nofollow" class="external text" href="https://www.ualberta.ca/~ersc/water/links/pembina.pdf">Oil and Troubled Waters: Reducing the impact of the oil and gas industry on Alberta's water resources</a> <span class="cs1-format">(PDF)</span> (Report). Edmonton, Alberta: Pembina Institute. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131215203350/http://www.ualberta.ca/~ersc/water/links/pembina.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2013-12-15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Oil+and+Troubled+Waters%3A+Reducing+the+impact+of+the+oil+and+gas+industry+on+Alberta%27s+water+resources&rft.place=Edmonton%2C+Alberta&rft.pub=Pembina+Institute&rft.date=2003-04&rft.aulast=Griffiths&rft.aufirst=Mary&rft.au=Woynillowicz%2C+Dan&rft_id=https%3A%2F%2Fwww.ualberta.ca%2F~ersc%2Fwater%2Flinks%2Fpembina.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-FMFNtoCEAAJun2012-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-FMFNtoCEAAJun2012_26-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFMFN2012" class="citation report cs1">FMFN (June 2012). <a rel="nofollow" class="external text" href="http://www.ceaa-acee.gc.ca/050/documents/p65505/81570E.pdf">Fort McKay's Review of Teck Resources Ltd. – Frontier Oil Sands Mine Project Integrated Application</a> <span class="cs1-format">(PDF)</span> (Report). Fort McKay First Nation. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130620145209/http://www.ceaa-acee.gc.ca/050/documents/p65505/81570E.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2013-06-20.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Fort+McKay%27s+Review+of+Teck+Resources+Ltd.+%E2%80%93+Frontier+Oil+Sands+Mine+Project+Integrated+Application&rft.pub=Fort+McKay+First+Nation&rft.date=2012-06&rft.au=FMFN&rft_id=http%3A%2F%2Fwww.ceaa-acee.gc.ca%2F050%2Fdocuments%2Fp65505%2F81570E.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-Science_and_Diplomacy.-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-Science_and_Diplomacy._27-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrittain2015" class="citation journal cs1">Brittain, John (22 June 2015). <a rel="nofollow" class="external text" href="http://www.sciencediplomacy.org/perspective/2015/international-atomic-energy-agency">"The International Atomic Energy Agency: Linking Nuclear Science and Diplomacy"</a>. <i>Science and Diplomacy</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Science+and+Diplomacy&rft.atitle=The+International+Atomic+Energy+Agency%3A+Linking+Nuclear+Science+and+Diplomacy&rft.date=2015-06-22&rft.aulast=Brittain&rft.aufirst=John&rft_id=http%3A%2F%2Fwww.sciencediplomacy.org%2Fperspective%2F2015%2Finternational-atomic-energy-agency&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-KonikowUSGSjan2013-28"><span class="mw-cite-backlink">^ <a href="#cite_ref-KonikowUSGSjan2013_28-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-KonikowUSGSjan2013_28-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKonikow" class="citation report cs1">Konikow, Leonard F. <a rel="nofollow" class="external text" href="https://pubs.usgs.gov/sir/2013/5079/SIR2013-5079.pdf">Groundwater Depletion in the United States (1900–2008)</a> <span class="cs1-format">(PDF)</span> (Report). Scientific Investigations Report. Reston, <a href="/wiki/Virginia" title="Virginia">VA</a>: U.S. Department of the Interior, U.S. Geological Survey. p. 63. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130615203529/http://pubs.usgs.gov/sir/2013/5079/SIR2013-5079.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2013-06-15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Groundwater+Depletion+in+the+United+States+%281900%E2%80%932008%29&rft.place=Reston%2C+VA&rft.series=Scientific+Investigations+Report&rft.pages=63&rft.pub=U.S.+Department+of+the+Interior%2C+U.S.+Geological+Survey&rft.aulast=Konikow&rft.aufirst=Leonard+F.&rft_id=http%3A%2F%2Fpubs.usgs.gov%2Fsir%2F2013%2F5079%2FSIR2013-5079.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-depletion-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-depletion_29-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFZabarenko2013" class="citation news cs1">Zabarenko, Deborah (20 May 2013). <a rel="nofollow" class="external text" href="https://www.reuters.com/article/us-usa-water-idUSBRE94J0Y920130520">"Drop in U.S. underground water levels has accelerated: USGS"</a>. <i>Reuters</i>. Washington, DC.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reuters&rft.atitle=Drop+in+U.S.+underground+water+levels+has+accelerated%3A+USGS&rft.date=2013-05-20&rft.aulast=Zabarenko&rft.aufirst=Deborah&rft_id=https%3A%2F%2Fwww.reuters.com%2Farticle%2Fus-usa-water-idUSBRE94J0Y920130520&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.edwardsaquifer.org/">"Edwards Aquifer Authority"</a>. Edwardsaquifer.org<span class="reference-accessdate">. Retrieved <span class="nowrap">15 December</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Edwards+Aquifer+Authority&rft.pub=Edwardsaquifer.org&rft_id=http%3A%2F%2Fwww.edwardsaquifer.org%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAquifer" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Aquifer&action=edit&section=22" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.un-igrac.org/">IGRAC International Groundwater Resources Assessment Centre</a></li> <li><a rel="nofollow" class="external text" href="https://gw-project.org/">The Groundwater Project</a> - Online platform for groundwater knowledge</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Physical_aquifer_properties_used_in_hydrogeology" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Aquiferproperties" title="Template:Aquiferproperties"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Aquiferproperties" title="Template talk:Aquiferproperties"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Aquiferproperties" title="Special:EditPage/Template:Aquiferproperties"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Physical_aquifer_properties_used_in_hydrogeology" style="font-size:114%;margin:0 4em">Physical <a class="mw-selflink selflink">aquifer</a> properties used in <a href="/wiki/Hydrogeology" title="Hydrogeology">hydrogeology</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hydraulic_head" title="Hydraulic head">hydraulic head</a></li> <li><a href="/wiki/Hydraulic_conductivity" title="Hydraulic conductivity">hydraulic conductivity</a></li> <li><a href="/wiki/Specific_storage" title="Specific storage">storativity</a></li> <li><a href="/wiki/Permeability_(earth_sciences)" class="mw-redirect" title="Permeability (earth sciences)">permeability</a></li> <li><a href="/wiki/Porosity" title="Porosity">porosity</a></li> <li><a href="/wiki/Water_content" title="Water content">water content</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Aquifers" style="padding:3px"><table class="nowraplinks hlist mw-collapsible {{{state=autocollapse}}} navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Aquifers" title="Template:Aquifers"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Aquifers" title="Template talk:Aquifers"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Aquifers" title="Special:EditPage/Template:Aquifers"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Aquifers" style="font-size:114%;margin:0 4em"><a class="mw-selflink selflink">Aquifers</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Canada</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Arkell_Spring_Grounds" title="Arkell Spring Grounds">Arkell Spring Grounds</a></li> <li><a href="/wiki/Laurentian_River_System" title="Laurentian River System">Laurentian River System</a></li> <li><a href="/wiki/Oak_Ridges_Moraine" title="Oak Ridges Moraine">Oak Ridges Moraine</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">United States</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Biscayne_Aquifer" title="Biscayne Aquifer">Biscayne Aquifer</a></li> <li><a href="/wiki/Bishop_Subbasin" title="Bishop Subbasin">Bishop Subbasin</a></li> <li><a href="/wiki/Buried_Valley_Aquifer_System" title="Buried Valley Aquifer System">Buried Valley Aquifer System</a></li> <li><a href="/wiki/Edwards_Aquifer" title="Edwards Aquifer">Edwards Aquifer</a></li> <li><a href="/wiki/Floridan_aquifer" title="Floridan aquifer">Floridan aquifer</a></li> <li><a href="/wiki/Fox_Hills_Formation" title="Fox Hills Formation">Fox Hills Formation</a></li> <li><a href="/wiki/Kirkwood%E2%80%93Cohansey_aquifer" title="Kirkwood–Cohansey aquifer">Kirkwood–Cohansey aquifer</a></li> <li><a href="/wiki/Mahomet_Aquifer" title="Mahomet Aquifer">Mahomet Aquifer</a></li> <li><a href="/wiki/Ogallala_Aquifer" title="Ogallala Aquifer">Ogallala Aquifer</a></li> <li><a href="/wiki/Permian_Basin_(North_America)" title="Permian Basin (North America)">Permian Basin</a></li> <li><a href="/wiki/San_Diego_Formation" title="San Diego Formation">San Diego Formation</a></li> <li><a href="/wiki/Sankoty_Aquifer" title="Sankoty Aquifer">Sankoty Aquifer</a></li> <li><a href="/wiki/Santa_Clara_valley_aquifer" title="Santa Clara valley aquifer">Santa Clara valley aquifer</a></li> <li><a href="/wiki/Snake_River_Aquifer" title="Snake River Aquifer">Snake River Aquifer</a></li> <li><a href="/wiki/Southern_Hills_Aquifer" title="Southern Hills Aquifer">Southern Hills Aquifer</a></li> <li><a href="/wiki/Turlock_Basin" title="Turlock Basin">Turlock Basin</a></li> <li><a href="/wiki/Wekepeke" title="Wekepeke">Wekepeke</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Mexico</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lake_Texcoco" title="Lake Texcoco">Lake Texcoco</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">South America</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Guarani_Aquifer" title="Guarani Aquifer">Guarani Aquifer</a></li> <li><a href="/wiki/Hamza_River" title="Hamza River">Hamza River</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Australia</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Botany_Sands_Aquifer" title="Botany Sands Aquifer">Botany Sands Aquifer</a></li> <li><a href="/wiki/Gnangara_Mound" title="Gnangara Mound">Gnangara Mound</a></li> <li><a href="/wiki/Great_Artesian_Basin" title="Great Artesian Basin">Great Artesian Basin</a></li> <li><a href="/wiki/Jandakot_Mound" title="Jandakot Mound">Jandakot Mound</a></li> <li><a href="/wiki/Yarragadee_Aquifer" title="Yarragadee Aquifer">Yarragadee Aquifer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">New Zealand</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Waiwhetu_Aquifer" title="Waiwhetu Aquifer">Waiwhetu Aquifer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Africa</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bas_Saharan_Basin" title="Bas Saharan Basin">Bas Saharan Basin</a></li> <li><a href="/wiki/Lotikipi_Basin_Aquifer" title="Lotikipi Basin Aquifer">Lotikipi Basin Aquifer</a></li> <li><a href="/wiki/Nubian_Sandstone_Aquifer_System" title="Nubian Sandstone Aquifer System">Nubian Sandstone Aquifer System</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Middle-East</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Yarkon-Taninim_Aquifer" title="Yarkon-Taninim Aquifer">Yarkon-Taninim Aquifer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Europe</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alnarpsstr%C3%B6mmen" title="Alnarpsströmmen">Alnarpsströmmen</a></li> <li><a href="/wiki/Schwyll_Aquifer" title="Schwyll Aquifer">Schwyll Aquifer</a></li> <li><a href="/wiki/Upper_Rhine_Plain" title="Upper Rhine Plain">Upper Rhine Plain</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related articles</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_aquifers" title="List of aquifers">List of aquifers</a></li> <li><a href="/wiki/Aquifers_in_the_United_States" class="mw-redirect" title="Aquifers in the United States">Aquifers in the United States</a></li> <li><a href="/wiki/Aquifer_storage_and_recovery" title="Aquifer storage and recovery">Aquifer storage and recovery</a></li> <li><a href="/wiki/Aquifer_test" title="Aquifer test">Aquifer test</a></li> <li><a href="/wiki/Artesian_aquifer" class="mw-redirect" title="Artesian aquifer">Artesian aquifer</a></li> <li><a href="/wiki/Sole_Source_Aquifer" title="Sole Source Aquifer">Sole Source Aquifer</a></li> <li><a href="/wiki/Surficial_aquifer" title="Surficial aquifer">Surficial aquifer</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><b><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Aquifers" title="Category:Aquifers">Category</a></b></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Natural_resources" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Natural_resources" title="Template:Natural resources"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Natural_resources" title="Template talk:Natural resources"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Natural_resources" title="Special:EditPage/Template:Natural resources"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Natural_resources" style="font-size:114%;margin:0 4em"><a href="/wiki/Natural_resource" title="Natural resource">Natural resources</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Atmosphere_of_Earth" title="Atmosphere of Earth">Air</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;"><a href="/wiki/Air_pollution" title="Air pollution">Pollution / quality</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/National_Ambient_Air_Quality_Standards" title="National Ambient Air Quality Standards">Ambient standards <span style="font-size:85%;">(US)</span></a></li> <li><a href="/wiki/Air_quality_index" title="Air quality index">Index</a></li> <li><a href="/wiki/Indoor_air_quality" title="Indoor air quality">Indoor</a></li> <li><a href="/wiki/Air_quality_law" title="Air quality law">Law</a> <ul><li><a href="/wiki/Clean_Air_Act_(United_States)" title="Clean Air Act (United States)">Clean Air Act <span style="font-size:85%;">(US)</span></a></li></ul></li> <li><a href="/wiki/Ozone_depletion" title="Ozone depletion">Ozone depletion</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;">Emissions</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Airshed" title="Airshed">Airshed</a></li> <li><a href="/wiki/Emissions_trading" title="Emissions trading">Trading</a></li> <li><a href="/wiki/Reducing_emissions_from_deforestation_and_forest_degradation" class="mw-redirect" title="Reducing emissions from deforestation and forest degradation">Deforestation (REDD)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Energy" title="Energy">Energy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bioenergy" title="Bioenergy">Bio</a></li> <li><a href="/wiki/Energy_law" title="Energy law">Law</a></li> <li><a href="/wiki/Energy_resources" class="mw-redirect" title="Energy resources">Resources</a></li> <li><a href="/wiki/Fossil_fuel" title="Fossil fuel">Fossil fuels</a> (<a href="/wiki/Fuel_gas" title="Fuel gas">gas</a>, <a href="/wiki/Peak_coal" title="Peak coal">peak coal</a>, <a href="/wiki/Peak_gas" title="Peak gas">peak gas</a>, <a href="/wiki/Peak_oil" title="Peak oil">peak oil</a>)</li> <li><a href="/wiki/Geothermal_energy" title="Geothermal energy">Geothermal</a></li> <li><a href="/wiki/Hydropower" title="Hydropower">Hydro</a></li> <li><a href="/wiki/Nuclear_power" title="Nuclear power">Nuclear</a></li> <li><a href="/wiki/Solar_energy" title="Solar energy">Solar</a> <ul><li><a href="/wiki/Sunlight" title="Sunlight">sunlight</a></li> <li><a href="/wiki/Shade_(shadow)" title="Shade (shadow)">shade</a></li></ul></li> <li><a href="/wiki/Wind_power" title="Wind power">Wind</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Land" title="Land">Land</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agricultural_land" title="Agricultural land">Agricultural</a> <ul><li><a href="/wiki/Arable_land" title="Arable land">arable</a> <ul><li><a href="/wiki/Peak_farmland" title="Peak farmland">peak farmland</a></li></ul></li></ul></li> <li><a href="/wiki/Land_degradation" title="Land degradation">Degradation</a></li> <li><a href="/wiki/Field_(agriculture)" title="Field (agriculture)">Field</a></li> <li><a href="/wiki/Landscape" title="Landscape">Landscape</a> <ul><li><a href="/wiki/Cityscape" title="Cityscape">cityscape</a></li> <li><a href="/wiki/Seascape" title="Seascape">seascape</a></li> <li><a href="/wiki/Soundscape" title="Soundscape">soundscape</a></li> <li><a href="/wiki/Viewshed" title="Viewshed">viewshed</a></li></ul></li> <li><a href="/wiki/Land_law" title="Land law">Law</a> <ul><li><a href="/wiki/Property_law" title="Property law">property</a></li></ul></li> <li><a href="/wiki/Land_management" title="Land management">Management</a> <ul><li><a href="/wiki/Habitat_conservation" title="Habitat conservation">habitat conservation</a></li></ul></li> <li><a href="/wiki/Mineral" title="Mineral">Minerals</a> <ul><li><a href="/wiki/Gemstone" title="Gemstone">gemstone</a></li> <li><a href="/wiki/Industrial_mineral" title="Industrial mineral">industrial</a></li> <li><a href="/wiki/Ore" title="Ore">ore</a> <ul><li><a href="/wiki/Metal" title="Metal">metal</a></li></ul></li> <li><a href="/wiki/Mining" title="Mining">mining</a> <ul><li><a href="/wiki/Mining_law" title="Mining law">law</a></li> <li><a href="/wiki/Sand_mining" title="Sand mining">sand</a></li></ul></li> <li><a href="/wiki/Peak_minerals" title="Peak minerals">peak</a> <ul><li><a href="/wiki/Peak_copper" class="mw-redirect" title="Peak copper">copper</a></li> <li><a href="/wiki/Peak_phosphorus" class="mw-redirect" title="Peak phosphorus">phosphorus</a></li></ul></li> <li><a href="/wiki/Mineral_rights" title="Mineral rights">rights</a></li></ul></li> <li><a href="/wiki/Soil" title="Soil">Soil</a> <ul><li><a href="/wiki/Soil_conservation" title="Soil conservation">conservation</a></li> <li><a href="/wiki/Soil_fertility" title="Soil fertility">fertility</a></li> <li><a href="/wiki/Soil_health" title="Soil health">health</a></li> <li><a href="/wiki/Soil_resilience" title="Soil resilience">resilience</a></li></ul></li> <li><a href="/wiki/Land_use" title="Land use">Use</a> <ul><li><a href="/wiki/Land-use_planning" title="Land-use planning">planning</a></li> <li><a href="/wiki/Open_space_reserve" title="Open space reserve">reserve</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Life" title="Life">Life</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Biodiversity" title="Biodiversity">Biodiversity</a></li> <li><a href="/wiki/Bioprospecting" title="Bioprospecting">Bioprospecting</a> <ul><li><a href="/wiki/Biopiracy" title="Biopiracy">biopiracy</a></li></ul></li> <li><a href="/wiki/Biosphere" title="Biosphere">Biosphere</a></li> <li><a href="/wiki/Bushfood" class="mw-redirect" title="Bushfood">Bushfood</a></li> <li><a href="/wiki/Bushmeat" title="Bushmeat">Bushmeat</a></li> <li><a href="/wiki/Fishery" title="Fishery">Fisheries</a> <ul><li><a href="/wiki/Climate_change_and_fisheries" title="Climate change and fisheries">climate change</a></li> <li><a href="/wiki/Fisheries_law" title="Fisheries law">law</a></li> <li><a href="/wiki/Fisheries_management" title="Fisheries management">management</a></li></ul></li> <li><a href="/wiki/Forest" title="Forest">Forests</a> <ul><li><a href="/wiki/Forest_genetic_resources" title="Forest genetic resources">genetic resources</a></li> <li><a href="/wiki/Forestry_law" title="Forestry law">law</a></li> <li><a href="/wiki/Forest_management" title="Forest management">management</a></li> <li><a href="/wiki/Non-timber_forest_product" title="Non-timber forest product">non-timber products</a></li></ul></li> <li><a href="/wiki/Game_(food)" class="mw-redirect" title="Game (food)">Game</a> <ul><li><a href="/wiki/Game_law" title="Game law">law</a></li></ul></li> <li><a href="/wiki/Marine_conservation" title="Marine conservation">Marine conservation</a></li> <li><a href="/wiki/Meadow" title="Meadow">Meadow</a></li> <li><a href="/wiki/Pasture" title="Pasture">Pasture</a></li> <li><a href="/wiki/Plant" title="Plant">Plants</a> <ul><li><a href="/wiki/Plant_Treaty" class="mw-redirect" title="Plant Treaty">FAO Plant Treaty</a></li> <li><a href="/wiki/Food" title="Food">food</a></li> <li><a href="/wiki/Plant_genetic_resources" title="Plant genetic resources">genetic resources</a></li> <li><a href="/wiki/Gene_bank" title="Gene bank">gene banks</a></li> <li><a href="/wiki/List_of_plants_used_in_herbalism" title="List of plants used in herbalism">herbal medicines</a></li> <li><a href="/wiki/UPOV" class="mw-redirect" title="UPOV">UPOV Convention</a></li> <li><a href="/wiki/Wood" title="Wood">wood</a></li></ul></li> <li><a href="/wiki/Rangeland" title="Rangeland">Rangeland</a></li> <li><a href="/wiki/Seed_bank" title="Seed bank">Seed bank</a></li> <li><a href="/wiki/Wildlife" title="Wildlife">Wildlife</a> <ul><li><a href="/wiki/Wildlife_conservation" title="Wildlife conservation">conservation</a></li> <li><a href="/wiki/Wildlife_management" title="Wildlife management">management</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Water" title="Water">Water</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;">Types / location</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">Aquifer</a> <ul><li><a href="/wiki/Aquifer_storage_and_recovery" title="Aquifer storage and recovery">storage and recovery</a></li></ul></li> <li><a href="/wiki/Drinking_water" title="Drinking water">Drinking</a></li> <li><a href="/wiki/Fresh_water" title="Fresh water">Fresh</a></li> <li><a href="/wiki/Groundwater" title="Groundwater">Groundwater</a> <ul><li><a href="/wiki/Groundwater_pollution" title="Groundwater pollution">pollution</a></li> <li><a href="/wiki/Groundwater_recharge" title="Groundwater recharge">recharge</a></li> <li><a href="/wiki/Groundwater_remediation" title="Groundwater remediation">remediation</a></li></ul></li> <li><a href="/wiki/Hydrosphere" title="Hydrosphere">Hydrosphere</a></li> <li><a href="/wiki/Ice" title="Ice">Ice</a> <ul><li><a href="/wiki/Iceberg" title="Iceberg">bergs</a></li> <li><a href="/wiki/Glacier" title="Glacier">glacial</a></li> <li><a href="/wiki/Polar_ice_cap" title="Polar ice cap">polar</a></li></ul></li> <li><a href="/wiki/Irrigation" title="Irrigation">Irrigation</a> <ul><li><i><a href="/wiki/Huerta" title="Huerta">huerta</a></i></li></ul></li> <li><a href="/wiki/Marine_resources" title="Marine resources">Marine</a></li> <li><a href="/wiki/Rain" title="Rain">Rain</a> <ul><li><a href="/wiki/Rainwater_harvesting" title="Rainwater harvesting">harvesting</a></li></ul></li> <li><a href="/wiki/Stormwater" title="Stormwater">Stormwater</a></li> <li><a href="/wiki/Surface_water" title="Surface water">Surface water</a></li> <li><a href="/wiki/Sewage" title="Sewage">Sewage</a> <ul><li><a href="/wiki/Reclaimed_water" title="Reclaimed water">reclaimed water</a></li></ul></li> <li><a href="/wiki/Drainage_basin" title="Drainage basin">Watershed</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;">Aspects</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Desalination" title="Desalination">Desalination</a></li> <li><a href="/wiki/Flood" title="Flood">Floods</a></li> <li><a href="/wiki/Water_law" class="mw-redirect" title="Water law">Law</a></li> <li><a href="/wiki/Leaching_(agriculture)" title="Leaching (agriculture)">Leaching</a></li> <li><a href="/wiki/Sanitation" title="Sanitation">Sanitation</a> <ul><li><a href="/wiki/Improved_sanitation" title="Improved sanitation">improved</a></li></ul></li> <li><a href="/wiki/Water_scarcity" title="Water scarcity">Scarcity</a></li> <li><a href="/wiki/Water_security" title="Water security">Security</a></li> <li><a href="/wiki/Water_supply" title="Water supply">Supply</a></li> <li><a href="/wiki/Water_efficiency" title="Water efficiency">Efficiency</a></li> <li><a href="/wiki/Water_conflict" title="Water conflict">Conflict</a></li> <li><a href="/wiki/Water_conservation" title="Water conservation">Conservation</a></li> <li><a href="/wiki/Peak_water" title="Peak water">Peak water</a></li> <li><a href="/wiki/Water_pollution" title="Water pollution">Pollution</a></li> <li><a href="/wiki/Water_privatization" title="Water privatization">Privatization</a></li> <li><a href="/wiki/Water_quality" title="Water quality">Quality</a></li> <li><a href="/wiki/Water_right" title="Water right">Right</a></li> <li><a href="/wiki/Water_resources" title="Water resources">Resources</a> <ul><li><a href="/wiki/Improved_water_source" title="Improved water source">improved</a></li> <li><a href="/wiki/Water_resource_policy" title="Water resource policy">policy</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Commons" title="Commons">Commons</a> <ul><li><a href="/wiki/Enclosure" title="Enclosure">enclosure</a></li> <li><a href="/wiki/Global_commons" title="Global commons">global</a></li> <li><a href="/wiki/Common_land" title="Common land">land</a></li> <li><a href="/wiki/Tragedy_of_the_commons" title="Tragedy of the commons">tragedy of</a></li></ul></li> <li><a href="/wiki/Natural_resource_economics" title="Natural resource economics">Economics</a> <ul><li><a href="/wiki/Ecological_economics" title="Ecological economics">ecological</a></li> <li><a href="/wiki/Land_(economics)" title="Land (economics)">land</a></li></ul></li> <li><a href="/wiki/Ecosystem_services" class="mw-redirect" title="Ecosystem services">Ecosystem services</a></li> <li><a href="/wiki/Exploitation_of_natural_resources" title="Exploitation of natural resources">Exploitation</a> <ul><li><a href="/wiki/Overexploitation" title="Overexploitation">overexploitation</a></li> <li><a href="/wiki/Earth_Overshoot_Day" title="Earth Overshoot Day">Earth Overshoot Day</a></li></ul></li> <li><a href="/wiki/Natural_resource_management" title="Natural resource management">Management</a> <ul><li><a href="/wiki/Adaptive_management" title="Adaptive management">adaptive</a></li></ul></li> <li><a href="/wiki/Natural_capital" title="Natural capital">Natural capital</a> <ul><li><a href="/wiki/Natural_capital_accounting" title="Natural capital accounting">accounting</a></li> <li><a href="/wiki/Environmental_good" title="Environmental good">good</a></li></ul></li> <li><a href="/wiki/Natural_heritage" title="Natural heritage">Natural heritage</a></li> <li><a href="/wiki/Nature_reserve" title="Nature reserve">Nature reserve</a> <ul><li><a href="/wiki/Remnant_natural_area" title="Remnant natural area">remnant natural area</a></li></ul></li> <li><a href="/wiki/Systems_ecology" title="Systems ecology">Systems ecology</a></li> <li><a href="/wiki/Urban_ecology" title="Urban ecology">Urban ecology</a></li> <li><a href="/wiki/Wilderness" title="Wilderness">Wilderness</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;"><a href="/wiki/Resource" title="Resource">Resource</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Common-pool_resource" title="Common-pool resource">Common-pool</a></li> <li><a href="/wiki/Conflict_resource" class="mw-redirect" title="Conflict resource">Conflict <span style="font-size:85%;">(perpetuation)</span></a></li> <li><a href="/wiki/Resource_curse" title="Resource curse">Curse</a></li> <li><a href="/wiki/Resource_depletion" title="Resource depletion">Depletion</a></li> <li><a href="/wiki/Resource_extraction" class="mw-redirect" title="Resource extraction">Extraction</a></li> <li><a href="/wiki/Resource_nationalism" title="Resource nationalism">Nationalism</a></li> <li><a href="/wiki/Renewable_resource" title="Renewable resource">Renewable</a> / <a href="/wiki/Non-renewable_resource" title="Non-renewable resource">Non-renewable</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Natural_resources" title="Category:Natural resources">Category</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Subterranea" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Subterranea" title="Template:Subterranea"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/w/index.php?title=Template_talk:Subterranea&action=edit&redlink=1" class="new" title="Template talk:Subterranea (page does not exist)"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Subterranea" title="Special:EditPage/Template:Subterranea"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Subterranea" style="font-size:114%;margin:0 4em"><a href="/wiki/Subterranea_(geography)" title="Subterranea (geography)">Subterranea</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Natural features</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Types</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alcove_(landform)" title="Alcove (landform)">Alcove</a></li> <li><a href="/wiki/Ant_colony" title="Ant colony">Ant colony</a></li> <li><a class="mw-selflink selflink">Aquifer</a></li> <li><a href="/wiki/Burrow" title="Burrow">Burrow</a> <ul><li><a href="/wiki/Burrow_fossil" title="Burrow fossil">Burrow fossil</a></li> <li><a href="/wiki/Communal_burrow" title="Communal burrow">Communal burrow</a></li> <li><a href="/wiki/Paleoburrow" title="Paleoburrow">Paleoburrow</a></li></ul></li> <li><a href="/wiki/Cave" title="Cave">Cave</a> <ul><li><a href="/wiki/Glacier_cave" title="Glacier cave">Glacier cave</a></li> <li><a href="/wiki/Grotto" title="Grotto">Grotto</a></li> <li><a href="/wiki/Ice_cave" title="Ice cave">Ice cave</a></li> <li><a href="/wiki/Lava_cave" title="Lava cave">Lava cave</a></li> <li><a href="/wiki/Lava_tube" title="Lava tube">Lava tube</a></li> <li><a href="/wiki/Pit_Cave" class="mw-redirect" title="Pit Cave">Pit Cave</a></li> <li><a href="/wiki/Show_cave" title="Show cave">Show cave</a></li> <li><a href="/wiki/Solutional_cave" title="Solutional cave">Solutional cave</a></li> <li><a href="/wiki/Talus_cave" title="Talus cave">Talus cave</a></li></ul></li> <li><a href="/wiki/Cenote" title="Cenote">Cenote</a></li> <li><a href="/wiki/Karst" title="Karst">Karst</a></li> <li><a href="/wiki/Lava_tree_mold" title="Lava tree mold">Lava tree mold</a></li> <li><a href="/wiki/Magma_chamber" title="Magma chamber">Magma chamber</a></li> <li><a href="/wiki/Maternity_den" title="Maternity den">Maternity den</a></li> <li><a href="/wiki/Nest" title="Nest">Nest</a> <ul><li><a href="/wiki/Beehive" title="Beehive">Bee</a></li></ul></li> <li><a href="/wiki/Pit_crater" title="Pit crater">Pit crater</a></li> <li><a href="/wiki/Rock_shelter" title="Rock shelter">Rock shelter</a></li> <li><a href="/wiki/Sinkhole" title="Sinkhole">Sinkhole</a></li> <li><a href="/wiki/Subterranean_fauna" title="Subterranean fauna">Subterranean fauna</a></li> <li><a href="/wiki/Subterranean_river" title="Subterranean river">Subterranean river</a></li> <li><a href="/wiki/Subterranean_waterfall" title="Subterranean waterfall">Subterranean waterfall</a></li> <li><a href="/wiki/Underground_lake" title="Underground lake">Underground lake</a></li> <li><a href="/wiki/Volcanic_pipe" title="Volcanic pipe">Volcanic pipe</a></li> <li><a href="/wiki/Warren_(burrow)" title="Warren (burrow)">Warren</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Exemplars</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Balve_Cave" title="Balve Cave">Balve Cave</a></li> <li><a href="/wiki/Castellana_Caves" title="Castellana Caves">Castellana Caves</a></li> <li><a href="/wiki/Hang_S%C6%A1n_%C4%90o%C3%B2ng" title="Hang Sơn Đoòng">Hang Sơn Đoòng</a></li> <li><a href="/wiki/Jewel_Cave_National_Monument" title="Jewel Cave National Monument">Jewel Cave National Monument</a></li> <li><a href="/wiki/Kazumura_Cave" title="Kazumura Cave">Kazumura Cave</a></li> <li><a href="/wiki/Lechuguilla_Cave" title="Lechuguilla Cave">Lechuguilla Cave</a></li> <li><a href="/wiki/Mammoth_Cave_National_Park" title="Mammoth Cave National Park">Mammoth Cave National Park</a></li> <li><a href="/wiki/Reed_Flute_Cave" title="Reed Flute Cave">Reed Flute Cave</a></li> <li><a href="/wiki/Subterranean_rivers_of_London" title="Subterranean rivers of London">Subterranean rivers of London</a></li> <li><a href="/wiki/Veryovkina_Cave" title="Veryovkina Cave">Veryovkina Cave</a></li> <li><a href="/wiki/Wind_Cave_National_Park" title="Wind Cave National Park">Wind Cave National Park</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Man-made features</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Types</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air_raid_shelter" title="Air raid shelter">Air raid shelter</a></li> <li><a href="/wiki/Basement" title="Basement">Basement</a></li> <li><a href="/wiki/Burial_vault_(tomb)" title="Burial vault (tomb)">Burial vault</a></li> <li><a href="/wiki/Borehole" title="Borehole">Borehole</a></li> <li><a href="/wiki/Bunker" title="Bunker">Bunker</a></li> <li><a href="/wiki/Blast_shelter" title="Blast shelter">Blast shelter</a></li> <li><a href="/wiki/Catacombs" title="Catacombs">Catacombs</a></li> <li><a href="/wiki/Casemate" title="Casemate">Casemate</a></li> <li><a href="/wiki/Mausoleum" title="Mausoleum">Crypt Mausoleum</a></li> <li><a href="/wiki/Dungeon" title="Dungeon">Dungeon</a></li> <li><a href="/wiki/Dugout_(shelter)" title="Dugout (shelter)">Dugout (shelter)</a></li> <li><a href="/wiki/Dry_well" title="Dry well">Dry well</a></li> <li><a href="/wiki/Earth_shelter" title="Earth shelter">Earth shelter</a></li> <li><a href="/wiki/Erdstall" title="Erdstall">Erdstall</a></li> <li><a href="/wiki/Fallout_shelter" title="Fallout shelter">Fallout shelter</a></li> <li><a href="/wiki/Fogou" title="Fogou">Fogou</a></li> <li><a href="/wiki/Defensive_fighting_position#Terminology" title="Defensive fighting position">Foxhole</a></li> <li><a href="/wiki/Hypogeum" title="Hypogeum">Hypogeum</a></li> <li><a href="/wiki/Manhole" title="Manhole">Manhole</a></li> <li><a href="/wiki/Mining" title="Mining">Mine</a></li> <li><a href="/wiki/Missile_launch_facility" title="Missile launch facility">Missile launch facility</a></li> <li><a href="/wiki/Passage_grave" title="Passage grave">Passage grave</a></li> <li><a href="/wiki/Quarry" title="Quarry">Quarry</a></li> <li><a href="/wiki/Rock-cut_tomb" title="Rock-cut tomb">Rock-cut tomb</a></li> <li><a href="/wiki/Root_cellar" title="Root cellar">Root cellar</a></li> <li><a href="/wiki/Tunnel" title="Tunnel">Tunnel</a></li> <li><a href="/wiki/Utility_vault" title="Utility vault">Utility vault</a></li> <li><a href="/wiki/Underground_city" title="Underground city">Underground city</a></li> <li><a href="/wiki/Underground_base" title="Underground base">Underground base</a></li> <li><a href="/wiki/Underground_hangar" title="Underground hangar">Underground hangar</a></li> <li><a href="/wiki/Well" title="Well">Well</a></li> <li><a href="/wiki/Wine_cave" title="Wine cave">Wine cave</a></li> <li><a href="/wiki/Rapid_transit" title="Rapid transit">Subway system</a></li> <li><a href="/wiki/Secret_passage" title="Secret passage">Secret passage</a></li> <li><a href="/wiki/Semi-basement" title="Semi-basement">Semi-basement</a></li> <li><a href="/wiki/Sewerage" title="Sewerage">Sewerage</a> <ul><li><a href="/wiki/Septic_tank" title="Septic tank">Septic tank</a></li></ul></li> <li><a href="/wiki/Stepwell" title="Stepwell">Stepwell</a></li> <li><a href="/wiki/Storm_cellar" title="Storm cellar">Storm cellar</a></li> <li><a href="/wiki/Smuggling_tunnel" title="Smuggling tunnel">Smuggling tunnel</a></li> <li><a href="/wiki/Spider_hole" title="Spider hole">Spider hole</a></li> <li><a href="/wiki/Ventilation_shaft" title="Ventilation shaft">Ventilation shaft</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Exemplars</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/816_Nuclear_Military_Plant" title="816 Nuclear Military Plant">816 Nuclear Military Plant</a></li> <li><a href="/wiki/Caves_of_Maastricht" title="Caves of Maastricht">Caves of Maastricht</a></li> <li><a href="/wiki/The_Caves_of_%C3%86giss%C3%AD%C3%B0a" title="The Caves of Ægissíða">The Caves of Ægissíða</a></li> <li><a href="/wiki/Heritage_of_Mercury._Almad%C3%A9n_and_Idrija" title="Heritage of Mercury. Almadén and Idrija"> Almadén Mercury Mines</a></li> <li><a href="/wiki/Coober_Pedy" title="Coober Pedy">Coober Pedy</a></li> <li><a href="/wiki/Cheyenne_Mountain_Complex" title="Cheyenne Mountain Complex">Cheyenne Mountain Complex</a></li> <li><a href="/wiki/Chicago_Tunnel_Company" title="Chicago Tunnel Company">Chicago Tunnel Company</a></li> <li><a href="/wiki/Houston_tunnel_system" title="Houston tunnel system">Houston tunnel system</a></li> <li><a href="/wiki/Kosvinsky_Kamen" title="Kosvinsky Kamen">Kosvinsky Kamen</a></li> <li><a href="/wiki/K%C5%91b%C3%A1nya_cellar_system" title="Kőbánya cellar system">Kőbánya cellar system</a></li> <li><a href="/wiki/Kome_Caves" title="Kome Caves">Kome Caves</a></li> <li><a href="/wiki/Underground_City_(Beijing)" title="Underground City (Beijing)">Underground City (Beijing)</a></li> <li><a href="/wiki/Underground_City,_Montreal" title="Underground City, Montreal">Underground City, Montreal</a></li> <li><a href="/wiki/Underground_Great_Wall_of_China" title="Underground Great Wall of China">Underground Great Wall of China</a></li> <li><a href="/wiki/Maginot_Line" title="Maginot Line">Maginot Line</a></li> <li><a href="/wiki/Mines_of_Paris" title="Mines of Paris">Mines of Paris</a></li> <li><a href="/wiki/Mustang_Caves" title="Mustang Caves">Mustang Caves</a></li> <li><a href="/wiki/Mount_Yamantau" title="Mount Yamantau">Mount Yamantau</a></li> <li><a href="/wiki/Mogao_Caves" title="Mogao Caves">Mogao Caves</a></li> <li><a href="/wiki/Naples_underground_geothermal_zone" title="Naples underground geothermal zone">Naples underground geothermal zone</a></li> <li><a href="/wiki/North_American_Aerospace_Defense_Command" class="mw-redirect" title="North American Aerospace Defense Command">North American Aerospace Defense Command</a></li> <li><a href="/wiki/Raven_Rock_Mountain_Complex" title="Raven Rock Mountain Complex">Raven Rock Mountain Complex</a></li> <li><a href="/wiki/Shanghai_tunnels" title="Shanghai tunnels">Shanghai tunnels</a></li> <li><a href="/wiki/Subterranean_London" title="Subterranean London">Subterranean London</a></li> <li><a href="/wiki/Subterranean_Toledo" title="Subterranean Toledo">Subterranean Toledo</a></li> <li><a href="/wiki/Turda_Salt_Mines" class="mw-redirect" title="Turda Salt Mines">Turda Salt Mines</a></li> <li><a href="/wiki/Yaodong" title="Yaodong">Yaodong</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Fictional features</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Types</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hollow_Earth" title="Hollow Earth">Hollow Earth</a></li> <li><a href="/wiki/Subterranean_fiction" title="Subterranean fiction">Subterranean fiction</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight: normal;">Exemplars</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Allegory_of_the_cave" title="Allegory of the cave">Allegory of the cave</a></li> <li><a href="/wiki/Batcave" title="Batcave">Batcave</a></li> <li><a href="/wiki/Greek_underworld" title="Greek underworld">Greek Underworld</a></li> <li><a href="/wiki/Journey_to_the_Center_of_the_Earth" title="Journey to the Center of the Earth">Journey to the Center of the Earth</a></li> <li><a href="/wiki/Moria_(Middle-earth)" class="mw-redirect" title="Moria (Middle-earth)">Moria (Middle-earth)</a></li> <li><a href="/wiki/Nome_Kingdom" class="mw-redirect" title="Nome Kingdom">Nome Kingdom</a></li> <li><a href="/wiki/Pellucidar" title="Pellucidar">Pellucidar</a></li> <li><a href="/wiki/Subterranea_(comics)" class="mw-redirect" title="Subterranea (comics)">Subterranea (comics)</a></li> <li><a href="/wiki/Tunnels_in_popular_culture" title="Tunnels in popular culture">Tunnels in popular culture</a></li> <li><a href="/wiki/Underdark" title="Underdark">Underdark</a></li> <li><a href="/wiki/Underland_(Narnia)" title="Underland (Narnia)">Underland (Narnia)</a></li> <li><a href="/wiki/Wonderland_(fictional_country)" title="Wonderland (fictional country)">Wonderland (fictional country)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organisations</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/American_Society_of_Reclamation_Sciences" title="American Society of Reclamation Sciences">American Society of Reclamation Sciences</a></li> <li><a href="/wiki/Bergamt" title="Bergamt">Bergamt</a></li> <li><a href="/wiki/Cave_Research_Foundation" title="Cave Research Foundation">Cave Research Foundation</a></li> <li><a href="/wiki/History_of_hard_rock_miners%27_organizations" title="History of hard rock miners' organizations">History of hard rock miners' organizations</a></li> <li><a href="/wiki/National_Mine_Map_Repository" title="National Mine Map Repository">National Mine Map Repository</a></li> <li><a href="/wiki/National_Mining_Association" title="National Mining Association">National Mining Association</a></li> <li><a href="/wiki/National_Speleological_Society" title="National Speleological Society">National Speleological Society</a> <ul><li><a href="/wiki/Grotto_(National_Speleological_Society)" title="Grotto (National Speleological Society)">Grotto</a></li></ul></li> <li><a href="/wiki/Institute_of_Materials,_Minerals_and_Mining" title="Institute of Materials, Minerals and Mining">Institute of Materials, Minerals and Mining</a></li> <li><a href="/wiki/Institution_of_Mining_Engineers" title="Institution of Mining Engineers">Institution of Mining Engineers</a></li> <li><a href="/wiki/International_Union_of_Speleology" title="International Union of Speleology">International Union of Speleology</a></li> <li><a href="/wiki/Research_Centre_for_Deep_Drilling" title="Research Centre for Deep Drilling">Research Centre for Deep Drilling</a></li> <li><a href="/wiki/Society_of_Economic_Geologists" title="Society of Economic Geologists">Society of Economic Geologists</a></li> <li><a href="/wiki/Southern_African_Institute_of_Mining_and_Metallurgy" title="Southern African Institute of Mining and Metallurgy">Southern African Institute of Mining and Metallurgy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cave_conservation" title="Cave conservation">Cave conservation</a></li> <li><a href="/wiki/Cave_dweller" title="Cave dweller">Cave dweller</a></li> <li><a href="/wiki/Cave_diving" title="Cave diving">Cave diving</a></li> <li><a href="/wiki/Cave_gate" title="Cave gate">Cave gate</a></li> <li><a href="/wiki/Cave_rescue" title="Cave rescue">Cave rescue</a></li> <li><a href="/wiki/Cave_painting" title="Cave painting">Cave painting</a></li> <li><a href="/wiki/Caving" title="Caving">Caving</a></li> <li><a href="/wiki/Civil_defense" title="Civil defense">Civil defense</a></li> <li><a href="/wiki/Tunnel_warfare" title="Tunnel warfare">Tunnel warfare</a></li> <li><a href="/wiki/Tunnel_network" title="Tunnel network">Tunnel network</a></li> <li><a href="/wiki/Trench_warfare" title="Trench warfare">Trench warfare</a></li> <li><a href="/wiki/Underground_construction" title="Underground construction">Underground construction</a> <ul><li><a href="/wiki/Tunnel_construction" title="Tunnel construction">Tunnel construction</a></li></ul></li> <li><a href="/wiki/Underground_living" title="Underground living">Underground living</a></li> <li><a href="/wiki/Mine_rescue" title="Mine rescue">Mine rescue</a></li> <li><a href="/wiki/Mine_exploration" title="Mine exploration">Mine exploration</a></li> <li><a href="/wiki/Mining_engineering" title="Mining engineering">Mining engineering</a></li> <li><a href="/wiki/Mole_people" title="Mole people">Mole people</a> <ul><li><a href="/wiki/Mole_people_(fiction)" title="Mole people (fiction)">in fiction</a></li></ul></li> <li><a href="/wiki/Speleology" title="Speleology">Speleology</a></li> <li><a href="/wiki/Subterranean_warfare" title="Subterranean warfare">Subterranean warfare</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><style data-mw-deduplicate="TemplateStyles:r1038841319">.mw-parser-output .tooltip-dotted{border-bottom:1px dotted;cursor:help}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1038841319"></div><div role="navigation" class="navbox authority-control" aria-labelledby="Authority_control_databases_frameless&#124;text-top&#124;10px&#124;alt=Edit_this_at_Wikidata&#124;link=https&#58;//www.wikidata.org/wiki/Q208791#identifiers&#124;class=noprint&#124;Edit_this_at_Wikidata" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Authority_control_databases_frameless&#124;text-top&#124;10px&#124;alt=Edit_this_at_Wikidata&#124;link=https&#58;//www.wikidata.org/wiki/Q208791#identifiers&#124;class=noprint&#124;Edit_this_at_Wikidata" style="font-size:114%;margin:0 4em"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q208791#identifiers" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">National</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://d-nb.info/gnd/4022375-9">Germany</a></span></li><li><span class="uid"><span class="rt-commentedText tooltip tooltip-dotted" title="Aquifers"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/sh85006264">United States</a></span></span></li><li><span class="uid"><span class="rt-commentedText tooltip tooltip-dotted" title="zvodně"><a rel="nofollow" class="external text" href="https://aleph.nkp.cz/F/?func=find-c&local_base=aut&ccl_term=ica=ph855476&CON_LNG=ENG">Czech Republic</a></span></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="http://olduli.nli.org.il/F/?func=find-b&local_base=NLX10&find_code=UID&request=987007294022905171">Israel</a></span></li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://catalog.archives.gov/id/10637702">NARA</a></span></li></ul></div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Aquifer&oldid=1255804936">https://en.wikipedia.org/w/index.php?title=Aquifer&oldid=1255804936</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Aquifers" title="Category:Aquifers">Aquifers</a></li><li><a href="/wiki/Category:Hydraulic_engineering" title="Category:Hydraulic engineering">Hydraulic engineering</a></li><li><a href="/wiki/Category:Hydrology" title="Category:Hydrology">Hydrology</a></li><li><a href="/wiki/Category:Hydrogeology" title="Category:Hydrogeology">Hydrogeology</a></li><li><a href="/wiki/Category:Water_and_the_environment" title="Category:Water and the environment">Water and the environment</a></li><li><a href="/wiki/Category:Bodies_of_water" title="Category:Bodies of water">Bodies of water</a></li><li><a href="/wiki/Category:Water_supply" title="Category:Water supply">Water supply</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Webarchive_template_wayback_links" title="Category:Webarchive template wayback links">Webarchive template wayback links</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Articles_with_excerpts" title="Category:Articles with excerpts">Articles with excerpts</a></li><li><a href="/wiki/Category:Pages_displaying_short_descriptions_of_redirect_targets_via_Module:Annotated_link" title="Category:Pages displaying short descriptions of redirect targets via Module:Annotated link">Pages displaying short descriptions of redirect targets via Module:Annotated link</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 6 November 2024, at 19:30<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Aquifer&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-57488d5c7d-tfngh","wgBackendResponseTime":239,"wgPageParseReport":{"limitreport":{"cputime":"1.150","walltime":"1.377","ppvisitednodes":{"value":6568,"limit":1000000},"postexpandincludesize":{"value":160547,"limit":2097152},"templateargumentsize":{"value":2248,"limit":2097152},"expansiondepth":{"value":16,"limit":100},"expensivefunctioncount":{"value":12,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":145740,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 1156.767 1 -total"," 29.61% 342.509 1 Template:Reflist"," 16.50% 190.849 9 Template:Annotated_link"," 12.67% 146.598 10 Template:Navbox"," 12.42% 143.639 2 Template:Excerpt"," 11.28% 130.428 5 Template:Cite_journal"," 8.44% 97.670 1 Template:Aquiferproperties"," 7.40% 85.557 1 Template:Short_description"," 6.31% 72.970 9 Template:Rp"," 5.59% 64.689 9 Template:R/superscript"]},"scribunto":{"limitreport-timeusage":{"value":"0.728","limit":"10.000"},"limitreport-memusage":{"value":17341589,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-57488d5c7d-qgqr9","timestamp":"20241128015402","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Aquifer","url":"https:\/\/en.wikipedia.org\/wiki\/Aquifer","sameAs":"http:\/\/www.wikidata.org\/entity\/Q208791","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q208791","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2002-04-03T21:07:21Z","dateModified":"2024-11-06T19:30:39Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/c\/c7\/Groundwater_flow.svg","headline":"permeable rock containing groundwater"}</script> </body> </html>