A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming...

high FeO, low potassium, and are composed of usually greater than 90% mafic minerals (dark colored, high magnesium and iron content). The Earth's mantle...

relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. Felsic refers...

volcanics. The hangingwall to the deposit is broadly related to a more mafic sequence of volcanic rocks, either andesite (examples being Whim Creek &...

feldspar (90–100%), with a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present. Anorthosites...

ultramafic-mafic intrusive complex consists of ultramafic peridotites and pyroxenites with associated chromitite layers toward the base with more mafic norites...

Gabbro (/ˈɡæbroʊ/ GAB-roh) is a phaneritic (coarse-grained), mafic intrusive igneous rock formed from the slow cooling of magnesium-rich and iron-rich...

consists largely of tonalitic and granodioritic gneisses and lesser amounts of mafic and ultramafic gneisses. It underlies and is largely concealed by thin,...

from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More...

of alkali metals. It is intermediate in composition between low-silica (mafic) gabbro and high-silica (felsic) granite. Diorite is found in mountain-building...

branches, the continuous (felsic minerals: feldspars) and the discontinuous (mafic minerals). The minerals at the top of the illustration (given aside) are...

TTG rocks were directly derived from preexisting mafic materials. The melting temperature of meta-mafic rocks (generally between 700 °C and 1000 °C) depends...

melting of crust rock from the heat of underlying mafic magmas. The lighter felsic magma floats on the mafic magma without significant mixing. Less commonly...

into four chemical types based on silica content: felsic, intermediate, mafic, and ultramafic. Felsic or silicic lavas have a silica content greater than...

felsic. Mafic rocks are primarily composed of biotite, hornblende, pyroxene and olivine. Generally, felsic rocks are light colored and mafic rocks are...

formation of a volcanic arc, the Tickalara Oceanic Arc. Sedimentary rocks, mafic volcanic and volcaniclastic rocks deposited in the Central Zone of the Lamboo...

Fractional crystallization of a mafic parent magma. Partial melting of crustal material. Magma mixing between felsic rhyolitic and mafic basaltic magmas in a magma...

into four chemical types based on silica content: felsic, intermediate, mafic, and ultramafic. Felsic or silicic magmas have a silica content greater...

together. The spinel petrogenesis in mafic magmatic rocks is strongly debated, but certainly results from mafic magma interaction with more evolved magma...

crystal mush.: 8  Two distinct mafic magmas were involved in the eruption, and a total volume of 3–5 km3 (0.72–1.20 cu mi) of mafic magma is atypically high...

resemblance to the modern ash beds of Cotopaxi, Krakatoa, and Mont Pelé. Mafic volcanism typically takes the form of Hawaiian eruptions that are nonexplosive...

fluid-mobile elements in the mantle, and the provision of evidence that oxidized mafic magmas bring base metals and sulfur from the mantle to form giant copper...

occurred simultaneously, with two definite episodes of magma activity, mafic and felsic, the former of which being chiefly composed of gabbro-heavy magma...

of mafic magma from the upper mantle. The different densities of felsic and mafic magma limit mixing, so that the silicic magma floats on the mafic magma...

Group consists predominantly of mafic volcanic and calcareous rocks. The Alwar Group mainly consists of arenaceous and mafic volcanic rocks. The Ajabgarh...

feldspar granite – Type of igneous rock rich in alkali feldspar Anorthosite – Mafic intrusive igneous rock composed predominantly of plagioclase Aplite – Fine-grained...

massive sulfides. The Blake River Megacaldera Complex consists of mainly mafic to intermediate volcanic flows and less abundant felsic volcanic flows and...

the few gemstones that occur in only one color. Peridot can be found in mafic and ultramafic rocks occurring in lava and peridotite xenoliths of the mantle...

"Petrological constraints on the recycling of mafic crystal mushes and intrusion of braided sills in the Torres del Paine Mafic Complex (Patagonia)" (PDF). Journal...

Brook Formation. Locally abundant rocks include tholeiitic to transitional mafic fragmental rocks and massive flows, as well as felsic tuffs, tholeiitic...