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<!DOCTYPE html> <html class="client-nojs" lang="en" dir="ltr"> <head> <meta charset="UTF-8"/> <title>AAPG Wiki</title> <script>document.documentElement.className="client-js";RLCONF={"wgBreakFrames":!1,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy","wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"Z-XTLGLQ7KKUtfwCwEgd1wAAARc","wgCSPNonce":!1,"wgCanonicalNamespace":"","wgCanonicalSpecialPageName":!1,"wgNamespaceNumber":0,"wgPageName":"Main_Page","wgTitle":"Main Page","wgCurRevisionId":28193,"wgRevisionId":28193,"wgArticleId":1,"wgIsArticle":!0,"wgIsRedirect":!1,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["No AFT"],"wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Main_Page","wgRelevantArticleId":1,"wgIsProbablyEditable":!1,"wgRelevantPageIsProbablyEditable":!1,"wgRestrictionEdit":["sysop"],"wgRestrictionMove":["sysop"],"wgIsMainPage":!0,"wgMFDisplayWikibaseDescriptions":{"search":!1, "nearby":!1,"watchlist":!1,"tagline":!1},"wgArticleFeedbackv5Permissions":{"aft-reader":!0,"aft-member":!1,"aft-editor":!1,"aft-monitor":!1,"aft-administrator":!1,"aft-oversighter":!1,"aft-noone":!1},"aftv5Article":{"id":1,"title":"Main Page","namespace":0,"categories":["No AFT"],"permissionLevel":!1}};RLSTATE={"site.styles":"ready","noscript":"ready","user.styles":"ready","user":"ready","user.options":"loading","skins.vector.styles.legacy":"ready","skins.vector.styles.responsive":"ready"};RLPAGEMODULES=["site","mediawiki.page.startup","mediawiki.page.ready","skins.vector.legacy.js","ext.articleFeedbackv5.startup"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.implement("user.options@1hzgi",function($,jQuery,require,module){/*@nomin*/mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); });});</script> <link rel="stylesheet" href="/load.php?lang=en&modules=skins.vector.styles.legacy%2Cresponsive&only=styles&skin=vector"/> <script async="" src="/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector"></script> <meta name="ResourceLoaderDynamicStyles" content=""/> <link rel="stylesheet" href="/load.php?lang=en&modules=site.styles&only=styles&skin=vector"/> <meta name="generator" content="MediaWiki 1.35.9"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <link rel="shortcut icon" href="/favicon.ico"/> <link rel="search" type="application/opensearchdescription+xml" href="/opensearch_desc.php" title="AAPG Wiki (en)"/> <link rel="EditURI" type="application/rsd+xml" href="https://wiki.aapg.org/api.php?action=rsd"/> <link rel="license" href="/AAPG_Wiki:Copyrights"/> <link rel="alternate" type="application/atom+xml" title="AAPG Wiki Atom feed" href="/index.php?title=Special:RecentChanges&feed=atom"/>  <script async src="https://www.googletagmanager.com/gtag/js?id=UA-48078680-2"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'UA-48078680-2'); // Legacy Universal Analytics gtag('config', 'G-M6HFVNFXRJ'); // New GA4 </script>  </head> <body class="mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-Main_Page rootpage-Main_Page skin-vector action-view skin-vector-legacy"> <div id="mw-page-base" class="noprint"></div> <div id="mw-head-base" class="noprint"></div> <div id="content" class="mw-body" role="main"> <a id="top"></a> <div id="siteNotice" class="mw-body-content"></div> <div class="mw-indicators mw-body-content"> </div> <h1 id="firstHeading" class="firstHeading" lang="en">Main Page</h1> <div id="bodyContent" class="mw-body-content"> <div id="siteSub" class="noprint">From AAPG Wiki</div> <div id="contentSub"></div> <div id="contentSub2"></div> <div id="jump-to-nav"></div> <a class="mw-jump-link" href="#mw-head">Jump to navigation</a> <a class="mw-jump-link" href="#searchInput">Jump to search</a> <div id="mw-content-text" lang="en" dir="ltr" class="mw-content-ltr"><div class="mw-parser-output"><div class="mpg-banner"> <p><span class="mpg-title"><b>Welcome to AAPG Wiki</b></span> </p><p><span class="mpg-subtitle">an encyclopedia of subsurface science • <a href="/AAPG_Wiki:About" title="AAPG Wiki:About">about the wiki</a></span> </p> <div style="height:3em;"></div> <div class="mpg-info"><b><a href="/Special:Statistics" title="Special:Statistics">940</a></b> articles • <b><a href="/Special:Statistics" title="Special:Statistics">0</a></b> active users</div> <div class="mpg-credit">Image credit: The Booklight, Flickr, <span class="noglossary">CC-BY</span></div> </div> <div class="mpg-text-block"> <p><b>Welcome to AAPG Wiki — a new wiki for subsurface geoscience in the energy industry.</b> </p><p>The wiki has been seeded with two AAPG volumes: <i>Methods in Exploration</i> #10, and <i>Treatise in Petroleum Geology</i> #3. 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