Gabbro

<p>Gabbro  is a <a href="/facts/Phaneritic/j5pQSmhr">phaneritic</a> (coarse-grained and magnesium- and iron-rich), <a href="/facts/Mafic/mVL7Ahuw">mafic</a> <a href="/facts/Intrusion/y65IUQps">intrusive</a> <a href="/facts/Igneous_rock/xeMJhUah">igneous rock</a> formed from the slow cooling <a href="/facts/Magma/hRotHju9">magma</a> into a <a href="/facts/Crystallinity/qA9S1duu">holocrystalline</a> mass deep beneath the <a href="/facts/Earth/HLLmDfj0">Earth</a>'s surface. Slow-cooling, coarse-grained gabbro is chemically equivalent to rapid-cooling, fine-grained <a href="/facts/Basalt/uhbwGPTb">basalt</a>. Much of the Earth's <a href="/facts/Oceanic_crust/0lGjI7jN">oceanic crust</a> is made of gabbro, formed at <a href="/facts/Mid-ocean_ridge/wYdgdSW3">mid-ocean ridges</a>. Gabbro is also found as <a href="/facts/Pluton/y65IUQps">plutons</a> associated with continental <a href="/facts/Volcanism/0s6p1eFJ">volcanism</a>. Due to its variant nature, the term <i>gabbro</i> may be applied loosely to a wide range of intrusive rocks, many of which are merely "gabbroic".  By rough analogy, gabbro is to <a href="/facts/Basalt/uhbwGPTb">basalt</a> as <a href="/facts/Granite/G2evuVKo">granite</a> is to <a href="/facts/Rhyolite/yKeR5Lut">rhyolite</a>.
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Gabbro open-in-new

Gabbro