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class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Mineralogy"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.4</span> <span>Mineralogy</span> </div> </a> <ul id="toc-Mineralogy-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Naming" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Naming"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Naming</span> </div> </a> <ul id="toc-Naming-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Composition_of_volcanic_rocks" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Composition_of_volcanic_rocks"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Composition of volcanic rocks</span> </div> </a> <ul id="toc-Composition_of_volcanic_rocks-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mechanical_behaviour_of_volcanic_rocks" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Mechanical_behaviour_of_volcanic_rocks"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Mechanical behaviour of volcanic rocks</span> </div> </a> <ul id="toc-Mechanical_behaviour_of_volcanic_rocks-sublist" class="vector-toc-list"> </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> </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 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href="https://ca.wikipedia.org/wiki/Roca_volc%C3%A0nica" title="Roca volcànica – Catalan" lang="ca" hreflang="ca" data-title="Roca volcànica" 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/Extruzivn%C3%AD_hornina" title="Extruzivní hornina – Czech" lang="cs" hreflang="cs" data-title="Extruzivní hornina" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Vulkanit" title="Vulkanit – German" lang="de" hreflang="de" data-title="Vulkanit" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Vulkaaniline_kivim" title="Vulkaaniline kivim – Estonian" lang="et" hreflang="et" data-title="Vulkaaniline kivim" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%97%CF%86%CE%B1%CE%B9%CF%83%CF%84%CE%B5%CE%B9%CE%BF%CE%B3%CE%B5%CE%BD%CE%AD%CF%82_%CF%80%CE%AD%CF%84%CF%81%CF%89%CE%BC%CE%B1" title="Ηφαιστειογενές πέτρωμα – Greek" lang="el" hreflang="el" data-title="Ηφαιστειογενές πέτρωμα" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Roca_volc%C3%A1nica" title="Roca volcánica – Spanish" lang="es" hreflang="es" data-title="Roca volcánica" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Vulkana_roko" title="Vulkana roko – Esperanto" lang="eo" hreflang="eo" data-title="Vulkana roko" 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/Arroka_bolkaniko" title="Arroka bolkaniko – Basque" lang="eu" hreflang="eu" data-title="Arroka bolkaniko" 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%B3%D9%86%DA%AF_%D8%A2%D8%AA%D8%B4%D9%81%D8%B4%D8%A7%D9%86%DB%8C" title="سنگ آتشفشانی – Persian" lang="fa" hreflang="fa" data-title="سنگ آتشفشانی" 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/Roche_volcanique" title="Roche volcanique – French" lang="fr" hreflang="fr" data-title="Roche volcanique" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Rocha_volc%C3%A1nica" title="Rocha volcánica – Galician" lang="gl" hreflang="gl" data-title="Rocha volcánica" 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/%ED%99%94%EC%82%B0%EC%95%94" title="화산암 – Korean" lang="ko" hreflang="ko" data-title="화산암" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D5%80%D6%80%D5%A1%D5%A2%D5%AD%D5%A1%D5%B5%D5%AB%D5%B6_%D5%A1%D5%BA%D5%A1%D6%80" title="Հրաբխային ապար – Armenian" lang="hy" hreflang="hy" data-title="Հրաբխային ապար" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%9C%E0%A5%8D%E0%A4%B5%E0%A4%BE%E0%A4%B2%E0%A4%BE%E0%A4%AE%E0%A5%81%E0%A4%96%E0%A5%80%E0%A4%AF_%E0%A4%B6%E0%A5%88%E0%A4%B2" title="ज्वालामुखीय शैल – Hindi" lang="hi" hreflang="hi" data-title="ज्वालामुखीय शैल" 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/Batuan_vulkanik" title="Batuan vulkanik – Indonesian" lang="id" hreflang="id" data-title="Batuan vulkanik" 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-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Gosberg" title="Gosberg – Icelandic" lang="is" hreflang="is" data-title="Gosberg" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A1%D7%9C%D7%A2_%D7%92%D7%A2%D7%A9%D7%99" title="סלע געשי – Hebrew" lang="he" hreflang="he" data-title="סלע געשי" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kw mw-list-item"><a href="https://kw.wikipedia.org/wiki/Karrek_danek" title="Karrek danek – Cornish" lang="kw" hreflang="kw" data-title="Karrek danek" data-language-autonym="Kernowek" data-language-local-name="Cornish" class="interlanguage-link-target"><span>Kernowek</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Vulkanit" title="Vulkanit – Luxembourgish" lang="lb" hreflang="lb" data-title="Vulkanit" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Batuan_gunung_berapi" title="Batuan gunung berapi – Malay" lang="ms" hreflang="ms" data-title="Batuan gunung berapi" 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-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Extrusief_gesteente" title="Extrusief gesteente – Dutch" lang="nl" hreflang="nl" data-title="Extrusief gesteente" 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/%E7%81%AB%E5%B1%B1%E5%B2%A9" title="火山岩 – Japanese" lang="ja" hreflang="ja" data-title="火山岩" 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/Dagbergart" title="Dagbergart – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Dagbergart" 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-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Dagbergart" title="Dagbergart – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Dagbergart" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Vulqon_tog%CA%BB_jinslari" title="Vulqon togʻ jinslari – Uzbek" lang="uz" hreflang="uz" data-title="Vulqon togʻ jinslari" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Vulkanit" title="Vulkanit – Low German" lang="nds" hreflang="nds" data-title="Vulkanit" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl badge-Q70893996 mw-list-item" title=""><a href="https://pl.wikipedia.org/wiki/Ska%C5%82y_wylewne" title="Skały wylewne – Polish" lang="pl" hreflang="pl" data-title="Skały wylewne" 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/Rocha_vulc%C3%A2nica" title="Rocha vulcânica – Portuguese" lang="pt" hreflang="pt" data-title="Rocha vulcânica" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Extruz%C3%ADvna_hornina" title="Extruzívna hornina – Slovak" lang="sk" hreflang="sk" data-title="Extruzívna hornina" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sr badge-Q70893996 mw-list-item" title=""><a href="https://sr.wikipedia.org/wiki/%D0%92%D1%83%D0%BB%D0%BA%D0%B0%D0%BD%D1%81%D0%BA%D0%B5_%D1%81%D1%82%D0%B5%D0%BD%D0%B5" title="Вулканске стене – Serbian" lang="sr" hreflang="sr" data-title="Вулканске стене" 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-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Vulkaniitti" title="Vulkaniitti – Finnish" lang="fi" hreflang="fi" data-title="Vulkaniitti" 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/Vulkaniska_bergarter" title="Vulkaniska bergarter – Swedish" lang="sv" hreflang="sv" data-title="Vulkaniska bergarter" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%AB%E0%B8%B4%E0%B8%99%E0%B8%A0%E0%B8%B9%E0%B9%80%E0%B8%82%E0%B8%B2%E0%B9%84%E0%B8%9F" title="หินภูเขาไฟ – Thai" lang="th" hreflang="th" data-title="หินภูเขาไฟ" 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/Volkanik_kaya" title="Volkanik kaya – Turkish" lang="tr" hreflang="tr" data-title="Volkanik kaya" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li 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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">"Volcanics" redirects here. For Volcanic pistols, see <a href="/wiki/Volcanic_Repeating_Arms" title="Volcanic Repeating Arms">Volcanic Repeating Arms</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">For the album, see <a href="/wiki/Volcanic_Rock_(album)" title="Volcanic Rock (album)">Volcanic Rock (album)</a>.</div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Ignimbrite.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Ignimbrite.jpg/220px-Ignimbrite.jpg" decoding="async" width="220" height="188" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Ignimbrite.jpg/330px-Ignimbrite.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Ignimbrite.jpg/440px-Ignimbrite.jpg 2x" data-file-width="600" data-file-height="513" /></a><figcaption><a href="/wiki/Ignimbrite" title="Ignimbrite">Ignimbrite</a>, a volcanic rock deposited by <a href="/wiki/Pyroclastic_flow" title="Pyroclastic flow">pyroclastic flows</a></figcaption></figure> <p><b>Volcanic rocks</b> (often shortened to <b>volcanics</b> in scientific contexts) are <a href="/wiki/Rock_(geology)" title="Rock (geology)">rocks</a> formed from <a href="/wiki/Lava" title="Lava">lava</a> erupted from a <a href="/wiki/Volcano" title="Volcano">volcano</a>. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into <a href="/wiki/Subvolcanic_rock" title="Subvolcanic rock">hypabyssal</a> and <a href="/wiki/Metamorphic_rock" title="Metamorphic rock">metamorphic rocks</a> and constitute an important element of some <a href="/wiki/Sediment" title="Sediment">sediments</a> and <a href="/wiki/Sedimentary_rock" title="Sedimentary rock">sedimentary rocks</a>. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of <a href="/wiki/Precambrian" title="Precambrian">Precambrian</a> <a href="/wiki/Shield_(geology)" title="Shield (geology)">shield</a> geology, the term "volcanic" is often applied to what are strictly <a href="/wiki/Metavolcanic_rock" title="Metavolcanic rock">metavolcanic rocks</a>. Volcanic rocks and sediment that form from <a href="/wiki/Magma" title="Magma">magma</a> erupted into the air are called "pyroclastics," and these are also technically sedimentary rocks. </p><p>Volcanic rocks are among the most common rock types on Earth's surface, particularly in the oceans. On land, they are very common at plate boundaries and in <a href="/wiki/Flood_basalt" title="Flood basalt">flood basalt provinces</a>. It has been estimated that volcanic rocks cover about 8% of the Earth's current land surface.<sup id="cite_ref-Wilkinson2008_1-0" class="reference"><a href="#cite_note-Wilkinson2008-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Characteristics">Characteristics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=1" title="Edit section: Characteristics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Setting_and_size">Setting and size</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=2" title="Edit section: Setting and size"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b>. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Volcanic_rock&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2011</span>)</i></span></div></td></tr></tbody></table> <ul><li><a href="/wiki/Lava" title="Lava">Lava</a></li> <li><a href="/wiki/Tephra" title="Tephra">Tephra</a></li> <li><a href="/wiki/Volcanic_bomb" title="Volcanic bomb">Volcanic bomb</a></li> <li><a href="/wiki/Lapilli" title="Lapilli">Lapilli</a></li> <li><a href="/wiki/Volcanic_ash" title="Volcanic ash">Volcanic ash</a></li></ul> <p><br /> </p> <table class="wikitable"> <caption>Classification of Volcaniclastic rocks and sediments<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><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> </caption> <tbody><tr> <td> </td> <td> </td> <th colspan="2">Pyroclastic deposit </th></tr> <tr> <th>Clast size in mm </th> <th>Pyroclast </th> <th>Primarily unconsolidated: tephra </th> <th>Primarily consolidated: pyroclastic rock </th></tr> <tr> <td>> 64 mm </td> <td>Bomb, block </td> <td>Agglomerate, bed of blocks or bomb, block tephra </td> <td>Agglomerate, pyroclastic breccia </td></tr> <tr> <td>64 to 2 mm </td> <td>Lapillus </td> <td>Layer, bed of lapilli or lapilli tephra </td> <td>Lapilli tuff </td></tr> <tr> <td>2 to 1/16 mm </td> <td>Coarse ash grain </td> <td>Coarse ash </td> <td>Coarse (ash tuff) </td></tr> <tr> <td class="nowrap">< 1/16 mm </td> <td>Fine ash grain (dust grain) </td> <td>Fine ash (dust) </td> <td>Fine (ash) tuff (dust tuff) </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Texture">Texture</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=3" title="Edit section: Texture"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:LvMS-Lvm.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5a/LvMS-Lvm.jpg/220px-LvMS-Lvm.jpg" decoding="async" width="220" height="289" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5a/LvMS-Lvm.jpg/330px-LvMS-Lvm.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5a/LvMS-Lvm.jpg/440px-LvMS-Lvm.jpg 2x" data-file-width="1770" data-file-height="2328" /></a><figcaption>Photomicrograph of a <a href="/wiki/Volcanic_lithic_fragment" class="mw-redirect" title="Volcanic lithic fragment">volcanic lithic fragment</a> (<a href="/wiki/Sand_grain" class="mw-redirect" title="Sand grain">sand grain</a>); upper picture is plane-polarized light, bottom picture is cross-polarized light, scale box at left-center is 0.25 millimeter.</figcaption></figure> <p>Volcanic rocks are usually fine-grained or <a href="/wiki/Aphanitic" class="mw-redirect" title="Aphanitic">aphanitic</a> to glass in texture. They often contain <a href="/wiki/Xenolith" title="Xenolith">clasts</a> of other <a href="/wiki/Rock_(geology)" title="Rock (geology)">rocks</a> and <a href="/wiki/Phenocryst" title="Phenocryst">phenocrysts</a>. Phenocrysts are <a href="/wiki/Crystal" title="Crystal">crystals</a> that are larger than the <a href="/wiki/Matrix_(geology)" title="Matrix (geology)">matrix</a> and are identifiable with the unaided <a href="/wiki/Human_eye" title="Human eye">eye</a>. <a href="/wiki/Rhomb_porphyry" class="mw-redirect" title="Rhomb porphyry">Rhomb porphyry</a> is an example with large <a href="/wiki/Rhombus" title="Rhombus">rhomb</a> shaped <a href="/wiki/Phenocrysts" class="mw-redirect" title="Phenocrysts">phenocrysts</a> embedded in a very fine grained matrix.<sup id="cite_ref-Oslo_4-0" class="reference"><a href="#cite_note-Oslo-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>Volcanic rocks often have a <a href="/wiki/Vesicular_texture" title="Vesicular texture">vesicular texture</a> caused by voids left by <a href="/wiki/Volatile_(astrogeology)#Igneous_petrology" title="Volatile (astrogeology)">volatiles</a> trapped in the molten <a href="/wiki/Lava" title="Lava">lava</a>. <a href="/wiki/Pumice" title="Pumice">Pumice</a> is a highly vesicular rock produced in <a href="/wiki/Explosive_eruption" title="Explosive eruption">explosive volcanic eruptions</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Chemistry">Chemistry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=4" title="Edit section: Chemistry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Most modern petrologists classify igneous rocks, including volcanic rocks, by their chemistry when dealing with their origin. The fact that different mineralogies and textures may be developed from the same initial <a href="/wiki/Magma" title="Magma">magmas</a> has led petrologists to rely heavily on chemistry to look at a volcanic rock's origin.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Classification_extrusive_rocks_EN.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0a/Classification_extrusive_rocks_EN.svg/290px-Classification_extrusive_rocks_EN.svg.png" decoding="async" width="290" height="201" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0a/Classification_extrusive_rocks_EN.svg/435px-Classification_extrusive_rocks_EN.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0a/Classification_extrusive_rocks_EN.svg/580px-Classification_extrusive_rocks_EN.svg.png 2x" data-file-width="750" data-file-height="520" /></a><figcaption><a href="/wiki/IUGS" class="mw-redirect" title="IUGS">IUGS</a> classification of <a href="/wiki/Aphanitic" class="mw-redirect" title="Aphanitic">aphanitic</a> volcanic rocks according to their relative alkali (Na<sub>2</sub>O + K<sub>2</sub>O) and silica (SiO<sub>2</sub>) weight contents. Blue area is roughly where alkaline rocks plot; yellow area where subalkaline rocks plot. Original source: *<style data-mw-deduplicate="TemplateStyles:r920966791">.mw-parser-output span.smallcaps{font-variant:small-caps}.mw-parser-output span.smallcaps-smaller{font-size:85%}</style><span class="smallcaps">Le Maitre, R.W.</span> (<i>ed.</i>); 1989: <i>A classification of igneous rocks and glossary of terms</i>, Blackwell Science, Oxford. </figcaption></figure> <p>The chemical classification of igneous rocks is based first on the total content of <a href="/wiki/Silicon" title="Silicon">silicon</a> and alkali metals (<a href="/wiki/Sodium" title="Sodium">sodium</a> and <a href="/wiki/Potassium" title="Potassium">potassium</a>) expressed as weight fraction of silica and alkali oxides (<a href="/wiki/Potassium_oxide" title="Potassium oxide">K<sub>2</sub>O</a> plus <a href="/wiki/Sodium_oxide" title="Sodium oxide">Na<sub>2</sub>O</a>). These place the rock in one of the fields of the <a href="/wiki/TAS_classification" title="TAS classification">TAS diagram</a>. <a href="/wiki/Ultramafic_rock" title="Ultramafic rock">Ultramafic rock</a> and <a href="/wiki/Carbonatite" title="Carbonatite">carbonatites</a> have their own specialized classification, but these rarely occur as volcanic rocks. Some fields of the TAS diagram are further subdivided by the ratio of potassium oxide to sodium oxide. Additional classifications may be made on the basis of other components, such as aluminum or iron content.<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><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><sup id="cite_ref-philpotts-ague-2009=139-148_8-0" class="reference"><a href="#cite_note-philpotts-ague-2009=139-148-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>Volcanic rocks are also broadly divided into subalkaline, alkaline, and peralkaline volcanic rocks. Subalkaline rocks are defined as rocks in which </p><p>SiO<sub>2</sub> < -3.3539 × 10<sup>−4</sup> × A<sup>6</sup> + 1.2030 × 10<sup>−2</sup> × A<sup>5</sup> - 1.5188 × 10<sup>−1</sup> × A<sup>4</sup> + 8.6096 × 10<sup>−1</sup> × A<sup>3</sup> - 2.1111 × A<sup>2</sup> + 3.9492 × A + 39.0 </p><p>where both silica and total alkali oxide content (A) are expressed as <a href="/wiki/Molar_fraction" class="mw-redirect" title="Molar fraction">molar fraction</a>. Because the TAS diagram uses weight fraction and the boundary between alkaline and subalkaline rock is defined in terms of molar fraction, the position of this curve on the TAS diagram is only approximate. Peralkaline volcanic rocks are defined as rocks having Na<sub>2</sub>O + K<sub>2</sub>O > Al<sub>2</sub>O<sub>3</sub>, so that some of the alkali oxides must be present as <a href="/wiki/Aegirine" title="Aegirine">aegirine</a> or sodic <a href="/wiki/Amphibole" title="Amphibole">amphibole</a> rather than <a href="/wiki/Feldspar" title="Feldspar">feldspar</a>.<sup id="cite_ref-irvine-baragar-1971_9-0" class="reference"><a href="#cite_note-irvine-baragar-1971-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-philpotts-ague-2009=139-148_8-1" class="reference"><a href="#cite_note-philpotts-ague-2009=139-148-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>The chemistry of volcanic rocks is dependent on two things: the initial composition of the primary magma and the subsequent differentiation. Differentiation of most magmas tends to increase the silica (<a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a>) content, mainly by <a href="/wiki/Fractional_crystallization_(geology)" title="Fractional crystallization (geology)">crystal fractionation</a>. The initial composition of most magmas is <a href="/wiki/Basalt" title="Basalt">basaltic</a>, albeit small differences in initial compositions may result in multiple differentiation series. The most common of these series are the <a href="/wiki/Tholeiitic_magma_series" title="Tholeiitic magma series">tholeiitic</a>, <a href="/wiki/Calc-alkaline" class="mw-redirect" title="Calc-alkaline">calc-alkaline</a>, and <a href="/wiki/Alkaline_magma_series" title="Alkaline magma series">alkaline</a>.<sup id="cite_ref-irvine-baragar-1971_9-1" class="reference"><a href="#cite_note-irvine-baragar-1971-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-philpotts-ague-2009=139-148_8-2" class="reference"><a href="#cite_note-philpotts-ague-2009=139-148-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Mineralogy">Mineralogy</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=5" title="Edit section: Mineralogy"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Most volcanic rocks share a number of common <a href="/wiki/Mineral" title="Mineral">minerals</a>. Differentiation of volcanic rocks tends to increase the silica (SiO<sub>2</sub>) content mainly by <a href="/wiki/Fractional_crystallization_(geology)" title="Fractional crystallization (geology)">fractional crystallization</a>. Thus, more evolved volcanic rocks tend to be richer in minerals with a higher amount of silica such as <a href="/wiki/Phyllosilicate" class="mw-redirect" title="Phyllosilicate">phyllo</a> and <a href="/wiki/Tectosilicate" class="mw-redirect" title="Tectosilicate">tectosilicates</a> including the feldspars, <a href="/wiki/Quartz" title="Quartz">quartz</a> <a href="/wiki/Polymorphism_(materials_science)" class="mw-redirect" title="Polymorphism (materials science)">polymorphs</a> and <a href="/wiki/Muscovite" title="Muscovite">muscovite</a>. While still dominated by silicates, more primitive volcanic rocks have mineral assemblages with less silica, such as <a href="/wiki/Olivine" title="Olivine">olivine</a> and the <a href="/wiki/Pyroxene" title="Pyroxene">pyroxenes</a>. <a href="/wiki/Bowen%27s_reaction_series" title="Bowen's reaction series">Bowen's reaction series</a> correctly predicts the order of formation of the most common minerals in volcanic rocks.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p><p>Occasionally, a magma may pick up crystals that crystallized from another magma; these crystals are called <a href="/wiki/Xenocryst" class="mw-redirect" title="Xenocryst">xenocrysts</a>. <a href="/wiki/Diamond" title="Diamond">Diamonds</a> found in <a href="/wiki/Kimberlite" title="Kimberlite">kimberlites</a> are rare but well-known xenocrysts; the kimberlites do not create the diamonds, but pick them up and transport them to the surface of the Earth.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="Naming">Naming</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=6" title="Edit section: Naming"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:LvMS-Lvv.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ad/LvMS-Lvv.jpg/220px-LvMS-Lvv.jpg" decoding="async" width="220" height="373" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ad/LvMS-Lvv.jpg/330px-LvMS-Lvv.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ad/LvMS-Lvv.jpg/440px-LvMS-Lvv.jpg 2x" data-file-width="1316" data-file-height="2231" /></a><figcaption>An aphanitic volcanic sand grain, with fine-grained groundmass, as seen under a <a href="/wiki/Petrographic_microscope" title="Petrographic microscope">petrographic microscope</a></figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Olivine_basalt2.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Olivine_basalt2.jpg/220px-Olivine_basalt2.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Olivine_basalt2.jpg/330px-Olivine_basalt2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/49/Olivine_basalt2.jpg/440px-Olivine_basalt2.jpg 2x" data-file-width="600" data-file-height="600" /></a><figcaption>Vesicular olivine basalt from <a href="/wiki/La_Palma" title="La Palma">La Palma</a> (green <a href="/wiki/Phenocrysts" class="mw-redirect" title="Phenocrysts">phenocrysts</a> are <a href="/wiki/Olivine" title="Olivine">olivine</a>).</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Pumice_on_20_dollars.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bd/Pumice_on_20_dollars.jpg/220px-Pumice_on_20_dollars.jpg" decoding="async" width="220" height="238" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bd/Pumice_on_20_dollars.jpg/330px-Pumice_on_20_dollars.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bd/Pumice_on_20_dollars.jpg/440px-Pumice_on_20_dollars.jpg 2x" data-file-width="1800" data-file-height="1948" /></a><figcaption>A 15-centimeter (5.9 in) piece of <a href="/wiki/Pumice" title="Pumice">pumice</a> supported by a rolled U.S. $20 bill demonstrates its very low density.</figcaption></figure> <p>Volcanic rocks are named according to both their <a href="/wiki/Chemical_composition" title="Chemical composition">chemical composition</a> and texture. <a href="/wiki/Basalt" title="Basalt">Basalt</a> is a very common volcanic rock with low <a href="/wiki/Silica" class="mw-redirect" title="Silica">silica</a> content. <a href="/wiki/Rhyolite" title="Rhyolite">Rhyolite</a> is a volcanic rock with high silica content. Rhyolite has silica content similar to that of <a href="/wiki/Granite" title="Granite">granite</a> while basalt is compositionally equal to <a href="/wiki/Gabbro" title="Gabbro">gabbro</a>. Intermediate volcanic rocks include <a href="/wiki/Andesite" title="Andesite">andesite</a>, <a href="/wiki/Dacite" title="Dacite">dacite</a>, <a href="/wiki/Trachyte" title="Trachyte">trachyte</a>, and <a href="/wiki/Latite" title="Latite">latite</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p><p><a href="/wiki/Pyroclastic_rock" title="Pyroclastic rock">Pyroclastic rocks</a> are the product of explosive volcanism. They are often <a href="/wiki/Felsic" title="Felsic">felsic</a> (high in silica). Pyroclastic rocks are often the result of volcanic debris, such as <a href="/wiki/Volcanic_ash" title="Volcanic ash">ash</a>, <a href="/wiki/Volcanic_bomb" title="Volcanic bomb">bombs</a> and <a href="/wiki/Tephra" title="Tephra">tephra</a>, and other <a href="/wiki/Volcanic" class="mw-redirect" title="Volcanic">volcanic</a> <a href="/wiki/Ejecta" title="Ejecta">ejecta</a>. Examples of pyroclastic rocks are <a href="/wiki/Tuff" title="Tuff">tuff</a> and <a href="/wiki/Ignimbrite" title="Ignimbrite">ignimbrite</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p><p>Shallow <a href="/wiki/Intrusion" class="mw-redirect" title="Intrusion">intrusions</a>, which possess structure similar to volcanic rather than <a href="/wiki/Pluton" class="mw-redirect" title="Pluton">plutonic</a> rocks, are also considered to be volcanic, shading into <a href="/wiki/Subvolcanic" class="mw-redirect" title="Subvolcanic">subvolcanic</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p><p>The terms lava stone and lava rock are more used by marketers than geologists, who would likely say "volcanic rock" (because <a href="/wiki/Lava" title="Lava">lava</a> is a molten liquid and <a href="/wiki/Rock_(geology)" title="Rock (geology)">rock</a> is solid). "Lava stone" may describe anything from a friable <a href="/wiki/Silicic" title="Silicic">silicic</a> <a href="/wiki/Pumice" title="Pumice">pumice</a> to solid <a href="/wiki/Mafic" title="Mafic">mafic</a> flow basalt, and is sometimes used to describe rocks that were never <a href="/wiki/Lava" title="Lava">lava</a>, but look as if they were (such as <a href="/wiki/Sedimentary" class="mw-redirect" title="Sedimentary">sedimentary</a> <a href="/wiki/Chinese_scholar%27s_rocks" class="mw-redirect" title="Chinese scholar's rocks">limestone with dissolution pitting</a>). To convey anything about the physical or chemical properties of the rock, a more specific term should be used; a good supplier will know what sort of volcanic rock they are selling.<sup id="cite_ref-what_10-0" class="reference"><a href="#cite_note-what-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Composition_of_volcanic_rocks">Composition of volcanic rocks</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=7" title="Edit section: Composition of volcanic rocks"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG/220px-Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG/330px-Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/99/Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG/440px-Aa_next_to_pahoehoe_lava_at_Craters_of_the_Moon_NM-750px.JPG 2x" data-file-width="750" data-file-height="563" /></a><figcaption><a href="/wiki/Lava#Volcanic_morphologies" title="Lava">ʻAʻā next to pāhoehoe lava</a> at the <a href="/wiki/Craters_of_the_Moon_National_Monument_and_Preserve" title="Craters of the Moon National Monument and Preserve">Craters of the Moon National Monument and Preserve</a>, Idaho, United States.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Latit_-_Boxberg,_Hocheifel.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Latit_-_Boxberg%2C_Hocheifel.jpg/220px-Latit_-_Boxberg%2C_Hocheifel.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Latit_-_Boxberg%2C_Hocheifel.jpg/330px-Latit_-_Boxberg%2C_Hocheifel.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Latit_-_Boxberg%2C_Hocheifel.jpg/440px-Latit_-_Boxberg%2C_Hocheifel.jpg 2x" data-file-width="2100" data-file-height="2100" /></a><figcaption>A German example of <a href="/wiki/Latite" title="Latite">latite</a>, a type of volcanic rock</figcaption></figure> <p>The sub-family of rocks that form from volcanic lava are called <a href="/wiki/Igneous_volcanic_rock" class="mw-redirect" title="Igneous volcanic rock">igneous volcanic rocks</a> (to differentiate them from igneous rocks that form from magma below the surface, called <a href="/wiki/Igneous_plutonic_rock" class="mw-redirect" title="Igneous plutonic rock">igneous plutonic rocks</a>). </p><p>The lavas of different volcanoes, when cooled and hardened, differ much in their appearance and composition. If a <a href="/wiki/Rhyolite" title="Rhyolite">rhyolite</a> lava-stream cools quickly, it can quickly freeze into a black glassy substance called <a href="/wiki/Obsidian" title="Obsidian">obsidian</a>. When filled with bubbles of gas, the same lava may form the spongy appearing <a href="/wiki/Pumice" title="Pumice">pumice</a>. Allowed to cool slowly, it forms a light-colored, uniformly solid rock called rhyolite.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Rhyolite_2013.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/be/Rhyolite_2013.jpg/220px-Rhyolite_2013.jpg" decoding="async" width="220" height="169" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/be/Rhyolite_2013.jpg/330px-Rhyolite_2013.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/be/Rhyolite_2013.jpg/440px-Rhyolite_2013.jpg 2x" data-file-width="1375" data-file-height="1058" /></a><figcaption>A sample of rhyolite</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Scoria_AmsterdamIsland_2_edit.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Scoria_AmsterdamIsland_2_edit.jpg/220px-Scoria_AmsterdamIsland_2_edit.jpg" decoding="async" width="220" height="203" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Scoria_AmsterdamIsland_2_edit.jpg/330px-Scoria_AmsterdamIsland_2_edit.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/73/Scoria_AmsterdamIsland_2_edit.jpg/440px-Scoria_AmsterdamIsland_2_edit.jpg 2x" data-file-width="2114" data-file-height="1947" /></a><figcaption>Basaltic <a href="/wiki/Scoria" title="Scoria">scoria</a> from <a href="/wiki/%C3%8Ele_Amsterdam" title="Île Amsterdam">Amsterdam Island</a> in the Indian Ocean</figcaption></figure> <p>The lavas, having cooled rapidly in contact with the air or water, are mostly finely crystalline or have at least fine-grained ground-mass representing that part of the viscous semi-crystalline lava flow that was still liquid at the moment of eruption. At this time they were exposed only to atmospheric pressure, and the steam and other gases, which they contained in great quantity were free to escape; many important modifications arise from this, the most striking being the frequent presence of numerous steam cavities (<a href="/wiki/Vesicular_texture" title="Vesicular texture">vesicular</a> structure) often drawn out to elongated shapes subsequently filled up with minerals by infiltration (<a href="/wiki/Amygdule" title="Amygdule">amygdaloidal</a> structure).<sup id="cite_ref-EB1911_11-0" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-lavasteine_13-0" class="reference"><a href="#cite_note-lavasteine-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><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> </p><p>As crystallization was going on while the mass was still creeping forward under the surface of the Earth, the latest formed minerals (in the <a href="/wiki/Matrix_(geology)" title="Matrix (geology)">ground-mass</a>) are commonly arranged in subparallel winding lines that follow the direction of movement (fluxion or fluidal structure)—and larger early minerals that previously crystallized may show the same arrangement. Most lavas fall considerably below their original temperatures before emitted. In their behavior, they present a close analogy to hot solutions of salts in water, which, when they approach the saturation temperature, first deposit a crop of large, well-formed crystals (labile stage) and subsequently precipitate clouds of smaller less perfect crystalline particles (metastable stage).<sup id="cite_ref-EB1911_11-1" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>In igneous rocks the first generation of crystals generally forms before the lava has emerged to the surface, that is to say, during the ascent from the subterranean depths to the crater of the volcano. It has frequently been verified by observation that freshly emitted lavas contain large crystals borne along in a molten, liquid mass. The large, well-formed, early crystals (<a href="/wiki/Phenocryst" title="Phenocryst">phenocrysts</a>) are said to be <a href="/wiki/Porphyritic" title="Porphyritic">porphyritic</a>; the smaller crystals of the surrounding matrix or ground-mass belong to the post-effusion stage. More rarely lavas are completely fused at the moment of ejection; they may then cool to form a non-porphyritic, finely crystalline rock, or if more rapidly chilled may in large part be non-crystalline or glassy (vitreous rocks such as obsidian, <a href="/wiki/Tachylyte" class="mw-redirect" title="Tachylyte">tachylyte</a>, <a href="/wiki/Pitchstone" title="Pitchstone">pitchstone</a>).<sup id="cite_ref-EB1911_11-2" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>A common feature of glassy rocks is the presence of rounded bodies (<a href="/wiki/Spherulites" class="mw-redirect" title="Spherulites">spherulites</a>), consisting of fine divergent fibres radiating from a center; they consist of imperfect crystals of feldspar, mixed with quartz or <a href="/wiki/Tridymite" title="Tridymite">tridymite</a>; similar bodies are often produced artificially in glasses that are allowed to cool slowly. Rarely these spherulites are hollow or consist of concentric shells with spaces between (<a href="/wiki/Lithophysae" class="mw-redirect" title="Lithophysae">lithophysae</a>). <a href="/wiki/Perlite" title="Perlite">Perlitic</a> structure, also common in glasses, consists of the presence of concentric rounded cracks owing to contraction on cooling.<sup id="cite_ref-EB1911_11-3" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Volcanic_rock.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/71/Volcanic_rock.jpg/220px-Volcanic_rock.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/71/Volcanic_rock.jpg/330px-Volcanic_rock.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/71/Volcanic_rock.jpg/440px-Volcanic_rock.jpg 2x" data-file-width="2048" data-file-height="1536" /></a><figcaption>Volcanic rocks, <a href="/wiki/Porto_Moniz" title="Porto Moniz">Porto Moniz</a>, <a href="/wiki/Madeira" title="Madeira">Madeira</a></figcaption></figure> <p>The phenocrysts or porphyritic minerals are not only larger than those of the ground-mass; as the matrix was still liquid when they formed they were free to take perfect crystalline shapes, without interference by the pressure of adjacent crystals. They seem to have grown rapidly, as they are often filled with enclosures of glassy or finely crystalline material like that of the ground-mass . Microscopic examination of the phenocrysts often reveals that they have had a complex history. Very frequently they show layers of different composition, indicated by variations in color or other optical properties; thus augite may be green in the center surrounded by various shades of brown; or they may be pale green centrally and darker green with strong <a href="/wiki/Pleochroism" title="Pleochroism">pleochroism</a> (aegirine) at the periphery.<sup id="cite_ref-EB1911_11-4" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>In the feldspars the center is usually richer in calcium than the surrounding layers, and successive zones may often be noted, each less calcic than those within it. Phenocrysts of quartz (and of other minerals), instead of sharp, perfect crystalline faces, may show rounded corroded surfaces, with the points blunted and irregular tongue-like projections of the matrix into the substance of the crystal. It is clear that after the mineral had crystallized it was partly again dissolved or corroded at some period before the matrix solidified.<sup id="cite_ref-EB1911_11-5" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>Corroded phenocrysts of <a href="/wiki/Biotite" title="Biotite">biotite</a> and <a href="/wiki/Hornblende" title="Hornblende">hornblende</a> are very common in some lavas; they are surrounded by black rims of <a href="/wiki/Magnetite" title="Magnetite">magnetite</a> mixed with pale green augite. The hornblende or biotite substance has proved unstable at a certain stage of consolidation, and has been replaced by a paramorph of augite and magnetite, which may partially or completely substitute for the original crystal but still retains its characteristic outlines.<sup id="cite_ref-EB1911_11-6" class="reference"><a href="#cite_note-EB1911-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Mechanical_behaviour_of_volcanic_rocks">Mechanical behaviour of volcanic rocks</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Volcanic_rock&action=edit&section=8" title="Edit section: Mechanical behaviour of volcanic rocks"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The mechanical behaviour of volcanic rocks is complicated by their complex microstructure.<sup id="cite_ref-HeapViolay2021_15-0" class="reference"><a href="#cite_note-HeapViolay2021-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Heap2015_16-0" class="reference"><a href="#cite_note-Heap2015-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> For example, attributes such as the partitioning of the void space (pores and microcracks), pore and crystal size and shape, and hydrothermal alteration can all vary widely in volcanic rocks and can all influence the resultant mechanical behaviour (e.g., Young's modulus, compressive and tensile strength, and the pressure at which they transition from brittle to ductile behaviour<sup id="cite_ref-HeapViolay2021_15-1" class="reference"><a href="#cite_note-HeapViolay2021-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup>). As for other crustal rocks, volcanic rocks are brittle and ductile at low and high effective confining pressures, respectively. Brittle behaviour is manifest as faults and fractures, and ductile behaviour can either be distributed (cataclastic pore collapse) or localised (compaction bands).<sup id="cite_ref-HeapViolay2021_15-2" class="reference"><a href="#cite_note-HeapViolay2021-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> Understanding the mechanical behaviour of volcanic rocks can help us better understand volcanic hazards, such as flank collapse.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2021)">citation needed</span></a></i>]</sup> </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=Volcanic_rock&action=edit&section=9" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Extrusive_rock" title="Extrusive rock">Extrusive rock</a></li> <li><a href="/wiki/Intrusive_rock" title="Intrusive rock">Intrusive rock</a></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=Volcanic_rock&action=edit&section=10" 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="cite-bracket" style="column-width: refs <sup id=" id="cite_ref-lavasteine_13-1"> <ol class="references"> <li id="cite_note-Wilkinson2008-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Wilkinson2008_1-0">^</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="CITEREFWilkinsonMcElroyKeslerPeters2008" class="citation journal cs1">Wilkinson, Bruce H; McElroy, Brandon J; Kesler, Stephen E; Peters, Shanan E; Rothman, Edward D (2008). "Global geologic maps are tectonic speedometers—Rates of rock cycling from area-age frequencies". <i>Geological Society of America Bulletin</i>. <b>121</b> (5–6): 760–79. <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/2009GSAB..121..760W">2009GSAB..121..760W</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1130%2FB26457.1">10.1130/B26457.1</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Geological+Society+of+America+Bulletin&rft.atitle=Global+geologic+maps+are+tectonic+speedometers%E2%80%94Rates+of+rock+cycling+from+area-age+frequencies&rft.volume=121&rft.issue=5%E2%80%936&rft.pages=760-79&rft.date=2008&rft_id=info%3Adoi%2F10.1130%2FB26457.1&rft_id=info%3Abibcode%2F2009GSAB..121..760W&rft.aulast=Wilkinson&rft.aufirst=Bruce+H&rft.au=McElroy%2C+Brandon+J&rft.au=Kesler%2C+Stephen+E&rft.au=Peters%2C+Shanan+E&rft.au=Rothman%2C+Edward+D&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" 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 id="CITEREFLe_BasStreckeisen1991" class="citation journal cs1">Le Bas, M. 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"The IUGS systematics of igneous rocks". <i>Journal of the Geological Society</i>. <b>148</b> (5): 825–33. <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/1991JGSoc.148..825L">1991JGSoc.148..825L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1144%2Fgsjgs.148.5.0825">10.1144/gsjgs.148.5.0825</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:28548230">28548230</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+the+Geological+Society&rft.atitle=The+IUGS+systematics+of+igneous+rocks&rft.volume=148&rft.issue=5&rft.pages=825-33&rft.date=1991&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A28548230%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1144%2Fgsjgs.148.5.0825&rft_id=info%3Abibcode%2F1991JGSoc.148..825L&rft.aulast=Le+Bas&rft.aufirst=M.+J.&rft.au=Streckeisen%2C+AL&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" 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 journal cs1"><a rel="nofollow" class="external text" href="http://www.bgs.ac.uk/downloads/start.cfm?id=7">"Rock Classification Scheme - Vol 1 - Igneous"</a>. <i>British Geological Survey: Rock Classification Scheme</i>. <b>1</b>. NERC: 1–52. 1999. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20161124091415/http://www.bgs.ac.uk/downloads/start.cfm?id=7">Archived</a> from the original on 24 November 2016.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=British+Geological+Survey%3A+Rock+Classification+Scheme&rft.atitle=Rock+Classification+Scheme+-+Vol+1+-+Igneous&rft.volume=1&rft.pages=1-52&rft.date=1999&rft_id=http%3A%2F%2Fwww.bgs.ac.uk%2Fdownloads%2Fstart.cfm%3Fid%3D7&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" class="Z3988"></span></span> </li> <li id="cite_note-Oslo-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-Oslo_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCorfuLarsen2020" class="citation journal cs1 cs1-prop-long-vol">Corfu, Fernando; Larsen, Bjørn Tore (December 2020). 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J.; Streckeisen, A. L. (1991). "The IUGS systematics of igneous rocks". <i>Journal of the Geological Society</i>. <b>148</b> (5): 825–833. <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/1991JGSoc.148..825L">1991JGSoc.148..825L</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=10.1.1.692.4446">10.1.1.692.4446</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/10.1144%2Fgsjgs.148.5.0825">10.1144/gsjgs.148.5.0825</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:28548230">28548230</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+the+Geological+Society&rft.atitle=The+IUGS+systematics+of+igneous+rocks&rft.volume=148&rft.issue=5&rft.pages=825-833&rft.date=1991&rft_id=https%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fsummary%3Fdoi%3D10.1.1.692.4446%23id-name%3DCiteSeerX&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A28548230%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1144%2Fgsjgs.148.5.0825&rft_id=info%3Abibcode%2F1991JGSoc.148..825L&rft.aulast=Le+Bas&rft.aufirst=M.+J.&rft.au=Streckeisen%2C+A.+L.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" 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 class="citation journal cs1"><a rel="nofollow" class="external text" href="http://nora.nerc.ac.uk/id/eprint/3223/1/RR99006.pdf">"Rock Classification Scheme - Vol 1 - Igneous"</a> <span class="cs1-format">(PDF)</span>. <i>British Geological Survey: Rock Classification Scheme</i>. <b>1</b>: 1–52. 1999.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=British+Geological+Survey%3A+Rock+Classification+Scheme&rft.atitle=Rock+Classification+Scheme+-+Vol+1+-+Igneous&rft.volume=1&rft.pages=1-52&rft.date=1999&rft_id=http%3A%2F%2Fnora.nerc.ac.uk%2Fid%2Feprint%2F3223%2F1%2FRR99006.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" 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 class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110930102012/http://geology.csupomona.edu/alert/igneous/igclass.htm">"Classification of igneous rocks"</a>. Archived from <a rel="nofollow" class="external text" href="http://geology.csupomona.edu/alert/igneous/igclass.htm">the original</a> on 30 September 2011.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Classification+of+igneous+rocks&rft_id=http%3A%2F%2Fgeology.csupomona.edu%2Falert%2Figneous%2Figclass.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" class="Z3988"></span></span> </li> <li id="cite_note-philpotts-ague-2009=139-148-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-philpotts-ague-2009=139-148_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-philpotts-ague-2009=139-148_8-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-philpotts-ague-2009=139-148_8-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPhilpottsAgue2009" class="citation book cs1">Philpotts, Anthony R.; Ague, Jay J. (2009). <i>Principles of igneous and metamorphic petrology</i> (2nd ed.). 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Retrieved <span class="nowrap">9 Sep</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=reddome.com&rft.atitle=What+is+Lava+Rock&rft_id=http%3A%2F%2Freddome.com%2Flava-rock.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" class="Z3988"></span></span> </li> <li id="cite_note-EB1911-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-EB1911_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-EB1911_11-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-EB1911_11-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-EB1911_11-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-EB1911_11-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-EB1911_11-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-EB1911_11-6"><sup><i><b>g</b></i></sup></a></span> <span class="reference-text"><span class="noprint"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png" decoding="async" width="12" height="13" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/18px-Wikisource-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/24px-Wikisource-logo.svg.png 2x" data-file-width="410" data-file-height="430" /></span></span> </span>One or more of the preceding sentences incorporates text from a publication now in the <a href="/wiki/Public_domain" title="Public domain">public domain</a>: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFlett1911" class="citation encyclopaedia cs1">Flett, John Smith (1911). 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href="https://search.worldcat.org/issn/0258-8900">0258-8900</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:233217231">233217231</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Bulletin+of+Volcanology&rft.atitle=The+mechanical+behaviour+and+failure+modes+of+volcanic+rocks%3A+a+review&rft.volume=83&rft.issue=33&rft.pages=33&rft.date=2021&rft_id=info%3Adoi%2F10.1007%2Fs00445-021-01447-2&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A233217231%23id-name%3DS2CID&rft.issn=0258-8900&rft_id=info%3Abibcode%2F2021BVol...83...33H&rft.aulast=Heap&rft.aufirst=Michael+J&rft.au=Violay%2C+Marie&rft_id=https%3A%2F%2Fdoi.org%2F10.1007%252Fs00445-021-01447-2&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" class="Z3988"></span></span> </li> <li id="cite_note-Heap2015-16"><span 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title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Bulletin+of+Volcanology&rft.atitle=Fracture+and+compaction+of+andesite+in+a+volcanic+edifice&rft.volume=77&rft.issue=55&rft.pages=55&rft.date=2015&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC4551152%23id-name%3DPMC&rft_id=info%3Apmid%2F26321781&rft_id=info%3Adoi%2F10.1007%2Fs00445-015-0938-7&rft_id=info%3Abibcode%2F2015BVol...77...55H&rft.aulast=Heap&rft.aufirst=Michael+J&rft.au=Farquharson%2C+Jamie&rft.au=Baud%2C+Patrick&rft.au=Lavall%C3%A9e%2C+Yan&rft.au=Reuschl%C3%A9%2C+Thierry&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC4551152&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVolcanic+rock" class="Z3988"></span></span> </li> </ol></div> <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 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navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Igneous_rocks" title="Template:Igneous rocks"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Igneous_rocks" title="Template talk:Igneous rocks"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Igneous_rocks" title="Special:EditPage/Template:Igneous rocks"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Common_igneous_rocks_classified_by_silicon_dioxide_content" style="font-size:114%;margin:0 4em">Common <a href="/wiki/Igneous_rock" title="Igneous rock">igneous rocks</a> classified by <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">silicon dioxide</a> content</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0;background:transparent;color:inherit;"><div style="padding:0px"><table class="navbox-columns-table" style="border-spacing: 0px; text-align:left;width:100%;"><tbody><tr><td class="navbox-abovebelow" style="font-weight:bold;">Type</td><td class="navbox-abovebelow" style="border-left:2px solid #fdfdfd;font-weight:bold;"><a href="/wiki/Ultramafic_rock" title="Ultramafic rock">Ultramafic</a><br /><45% <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a></td><td class="navbox-abovebelow" style="border-left:2px solid #fdfdfd;font-weight:bold;"><a href="/wiki/Mafic" title="Mafic">Mafic</a><br />45–52% <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a></td><td class="navbox-abovebelow" style="border-left:2px solid #fdfdfd;font-weight:bold;"><a href="/wiki/Intermediate_composition" title="Intermediate composition">Intermediate</a><br />52–63% <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a></td><td class="navbox-abovebelow" style="border-left:2px solid #fdfdfd;font-weight:bold;"><a href="/wiki/Intermediate_composition" title="Intermediate composition">Intermediate</a>–<a href="/wiki/Felsic" title="Felsic">felsic</a><br />63–69% <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a></td><td class="navbox-abovebelow" style="border-left:2px solid #fdfdfd;font-weight:bold;"><a href="/wiki/Felsic" title="Felsic">Felsic</a><br />>69% <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">SiO<sub>2</sub></a></td></tr><tr style="vertical-align:top"><td class="navbox-list" style="padding:0px;text-align: center;width:12%;"><div> <p><b><a class="mw-selflink selflink">Volcanic rocks</a>:</b><br /><b><a href="/wiki/Subvolcanic_rock" title="Subvolcanic rock">Subvolcanic rocks</a>:</b><br /><b><a href="/wiki/Pluton" class="mw-redirect" title="Pluton">Plutonic rocks</a>:</b> </p> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;text-align: center;width:12%;"><div> <p><a href="/wiki/Picrite_basalt" title="Picrite basalt">Picrite basalt</a><br /><br /><a href="/wiki/Peridotite" title="Peridotite">Peridotite</a> </p> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;text-align: center;width:12%;"><div> <p><a href="/wiki/Basalt" title="Basalt">Basalt</a><br /><a href="/wiki/Diabase" title="Diabase">Diabase (Dolerite)</a><br /><a href="/wiki/Gabbro" title="Gabbro">Gabbro</a> </p> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;text-align: center;width:12%;"><div> <p><a href="/wiki/Andesite" title="Andesite">Andesite</a><br /><a href="/wiki/Diorite" title="Diorite">Microdiorite</a><br /><a href="/wiki/Diorite" title="Diorite">Diorite</a> </p> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;text-align: center;width:12%;"><div> <p><a href="/wiki/Dacite" title="Dacite">Dacite</a><br /><a href="/wiki/Granodiorite" title="Granodiorite">Microgranodiorite</a><br /><a href="/wiki/Granodiorite" title="Granodiorite">Granodiorite</a> </p> </div></td><td class="navbox-list" style="border-left:2px solid #fdfdfd;padding:0px;text-align: center;width:12%;"><div> <p><a href="/wiki/Rhyolite" title="Rhyolite">Rhyolite</a><br /><a href="/wiki/Granite" title="Granite">Microgranite</a><br /><a href="/wiki/Granite" title="Granite">Granite</a> </p> </div></td></tr></tbody></table></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="Volcanoes" 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="3" style="text-align:center;"><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:Volcanoes" title="Template:Volcanoes"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Volcanoes" title="Template talk:Volcanoes"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Volcanoes" title="Special:EditPage/Template:Volcanoes"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Volcanoes" style="font-size:114%;margin:0 4em"><a href="/wiki/Volcano" title="Volcano">Volcanoes</a></div></th></tr><tr><th scope="row" class="navbox-group" style="text-align:center;;width:1%">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/Caldera" title="Caldera">Caldera</a></li> <li><a href="/wiki/Cinder_cone" title="Cinder cone">Cinder cone</a></li> <li><a href="/wiki/Complex_volcano" title="Complex volcano">Complex volcano</a></li> <li><a href="/wiki/Cryovolcano" title="Cryovolcano">Cryovolcano</a></li> <li><a href="/wiki/Cryptoexplosion" title="Cryptoexplosion">Cryptovolcanic structure</a></li> <li><a href="/wiki/Fissure_vent" title="Fissure vent">Fissure vent</a></li> <li>Lava cone</li> <li><a href="/wiki/Lava_dome" title="Lava dome">Lava dome</a></li> <li><a href="/wiki/Maar" title="Maar">Maar</a></li> <li><a href="/wiki/Mud_volcano" title="Mud volcano">Mud volcano</a></li> <li><a href="/wiki/Parasitic_cone" title="Parasitic cone">Parasitic cone</a></li> <li><a href="/wiki/Pyroclastic_cone" class="mw-redirect" title="Pyroclastic cone">Pyroclastic cone</a></li> <li><a href="/wiki/Pyroclastic_shield" title="Pyroclastic shield">Pyroclastic shield</a></li> <li><a href="/wiki/Rootless_cone" title="Rootless cone">Rootless cone</a></li> <li><a href="/wiki/Shield_volcano" title="Shield volcano">Shield volcano</a></li> <li><a href="/wiki/Somma_volcano" title="Somma volcano">Somma volcano</a></li> <li><a href="/wiki/Stratovolcano" title="Stratovolcano">Stratovolcano</a></li> <li><a href="/wiki/Subglacial_volcano" title="Subglacial volcano">Subglacial volcano</a></li> <li><a href="/wiki/Submarine_volcano" title="Submarine volcano">Submarine volcano</a></li> <li><a href="/wiki/Supervolcano" title="Supervolcano">Supervolcano</a></li> <li><a href="/wiki/Tossol" title="Tossol">Tossol</a></li> <li><a href="/wiki/Volcanic_cone" title="Volcanic cone">Volcanic cone</a></li> <li><a href="/wiki/Harmonic_tremor" title="Harmonic tremor">Harmonic tremor</a></li></ul> </div></td><td class="noviewer navbox-image" rowspan="3" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/File:Puu_Oo_cropped.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Puu_Oo_cropped.jpg/90px-Puu_Oo_cropped.jpg" decoding="async" width="90" height="62" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Puu_Oo_cropped.jpg/135px-Puu_Oo_cropped.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Puu_Oo_cropped.jpg/180px-Puu_Oo_cropped.jpg 2x" data-file-width="845" data-file-height="578" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="text-align:center;;width:1%"><a class="mw-selflink selflink">Volcanic rocks</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/Agglomerate" title="Agglomerate">Agglomerate</a></li> <li><a href="/wiki/Andesite" title="Andesite">Andesite</a></li> <li><a href="/wiki/Basalt" title="Basalt">Basalt</a></li> <li><a href="/wiki/Basaltic_andesite" title="Basaltic andesite">Basaltic andesite</a></li> <li><a href="/wiki/Benmoreite" title="Benmoreite">Benmoreite</a></li> <li><a href="/wiki/Blairmorite" title="Blairmorite">Blairmorite</a></li> <li><a href="/wiki/Scoria" title="Scoria">Cinder</a></li> <li><a href="/wiki/Dacite" title="Dacite">Dacite</a></li> <li><a href="/wiki/Felsite" title="Felsite">Felsite</a></li> <li><a href="/wiki/Ignimbrite" title="Ignimbrite">Ignimbrite</a></li> <li><a href="/wiki/Komatiite" title="Komatiite">Komatiite</a></li> <li><a href="/wiki/Lapilli" title="Lapilli">Lapilli</a></li> <li><a href="/wiki/Latite" title="Latite">Latite</a></li> <li><a href="/wiki/Leucitite" title="Leucitite">Leucitite</a></li> <li><a href="/wiki/Nephelinite" title="Nephelinite">Nephelinite</a></li> <li><a href="/wiki/Obsidian" title="Obsidian">Obsidian</a></li> <li><a href="/wiki/Phonolite" title="Phonolite">Phonolite</a></li> <li><a href="/wiki/Phonotephrite" title="Phonotephrite">Phonotephrite</a></li> <li><a href="/wiki/Pumice" title="Pumice">Pumice</a></li> <li><a href="/wiki/Rhyodacite" title="Rhyodacite">Rhyodacite</a></li> <li><a href="/wiki/Rhyolite" title="Rhyolite">Rhyolite</a></li> <li><a href="/wiki/Tephra" title="Tephra">Tephra</a></li> <li><a href="/wiki/Tephriphonolite" title="Tephriphonolite">Tephriphonolite</a></li> <li><a href="/wiki/Trachyandesite" title="Trachyandesite">Trachyandesite</a></li> <li><a href="/wiki/Trachybasalt" title="Trachybasalt">Trachybasalt</a></li> <li><a href="/wiki/Trachyte" title="Trachyte">Trachyte</a></li> <li><a href="/wiki/Tuff" title="Tuff">Tuff</a></li> <li><a href="/wiki/Pyroclastic_fall" title="Pyroclastic fall">Pyroclastic fall</a></li> <li><a href="/wiki/Pyroclastic_flow" title="Pyroclastic flow">Pyroclastic flow</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="text-align:center;;width:1%">Lists and groups</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/Hotspot_(geology)" title="Hotspot (geology)">Hotspot</a></li> <li><a href="/wiki/Lists_of_volcanoes" title="Lists of volcanoes">Lists of volcanoes</a></li> <li><a href="/wiki/List_of_volcanic_eruptions_by_death_toll" title="List of volcanic eruptions by death toll">Eruptions by death toll</a></li> <li><a href="/wiki/Decade_Volcanoes" title="Decade Volcanoes">Decade Volcanoes</a></li> <li><a href="/wiki/Volcanic_arc" title="Volcanic arc">Volcanic arc</a></li> <li><a href="/wiki/Volcanic_belt" title="Volcanic belt">Volcanic belt</a></li> <li><a href="/wiki/Volcanic_field" title="Volcanic field">Volcanic field</a> <ul><li><a href="/wiki/Monogenetic_volcanic_field" title="Monogenetic volcanic field">monogenetic</a></li> <li><a href="/wiki/Polygenetic_volcanic_field" title="Polygenetic volcanic field">polygenetic</a></li></ul></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="3" style="text-align:center;"><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> <b><a href="/wiki/Category:Volcanoes" title="Category:Volcanoes">Category</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <b><a href="https://commons.wikimedia.org/wiki/Category:Volcanoes" class="extiw" title="commons:Category:Volcanoes">Commons</a></b></li> <li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Symbol_portal_class.svg" class="mw-file-description" title="Portal"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/16px-Symbol_portal_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/23px-Symbol_portal_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/31px-Symbol_portal_class.svg.png 2x" data-file-width="180" data-file-height="185" /></a></span> <b><a href="/wiki/Portal:Volcanoes" title="Portal:Volcanoes">Portal</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="WikiProject"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/37/People_icon.svg/16px-People_icon.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/37/People_icon.svg/24px-People_icon.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/37/People_icon.svg/32px-People_icon.svg.png 2x" data-file-width="100" data-file-height="100" /></span></span> <b><a href="/wiki/Wikipedia:WikiProject_Volcanoes" title="Wikipedia:WikiProject Volcanoes">WikiProject</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 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/Q108689#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/Q108689#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/Q108689#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/4152764-1">Germany</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/sh85144250">United States</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://catalogue.bnf.fr/ark:/12148/cb12264522p">France</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://data.bnf.fr/ark:/12148/cb12264522p">BnF data</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://id.ndl.go.jp/auth/ndlna/00565266">Japan</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://www.nli.org.il/en/authorities/987007543698105171">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="http://esu.com.ua/search_articles.php?id=30106">Encyclopedia of Modern Ukraine</a></span><ul><li><span class="uid"><a rel="nofollow" class="external text" href="http://esu.com.ua/search_articles.php?id=18090">2</a></span></li></ul></li></ul></div></td></tr></tbody></table></div>    </div><noscript><img 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