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  2. Ultramafic rock - Wikipedia

    en.wikipedia.org/wiki/Ultramafic_rock

    Peridotite, a type of ultramafic rock. Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are composed of usually greater than 90% mafic minerals (dark colored, high magnesium and iron content).

  3. Phreatomagmatic eruption - Wikipedia

    en.wikipedia.org/wiki/Phreatomagmatic_eruption

    Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water. They differ from exclusively magmatic eruptions and phreatic eruptions. Unlike phreatic eruptions, the products of phreatomagmatic eruptions contain juvenile (magmatic) clasts. [1] It is common for a large explosive eruption to have magmatic and ...

  4. Magmatism along strike-slip faults - Wikipedia

    en.wikipedia.org/wiki/Magmatism_along_strike...

    Strike-slip faults have a direct effect on magmatism. They can either induce magmatism, act as a conduit to magmatism and magmatic flow, or block magmatic flow. [3][4] In contrast, magmatism can also directly impact on strike-slip faults by determining fault formation, propagation and slip. [5] Both magma and strike-slip faults coexist and ...

  5. Anorthosite - Wikipedia

    en.wikipedia.org/wiki/Anorthosite

    Anorthosite (/ əˈnɔːrθəsaɪt /) is a phaneritic, intrusive igneous rock characterized by its composition: mostly plagioclase feldspar (90–100%), with a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present. Anorthosites are of enormous geologic interest, because it is ...

  6. Komatiite - Wikipedia

    en.wikipedia.org/wiki/Komatiite

    Komatiite. Komatiite / koʊˈmɑːtiˌaɪt / is a type of ultramafic mantle -derived volcanic rock defined as having crystallised from a lava of at least 18 wt% magnesium oxide (MgO). [1] It is classified as a 'picritic rock'. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content.

  7. Magma - Wikipedia

    en.wikipedia.org/wiki/Magma

    Magma (from Ancient Greek μάγμα (mágma) 'thick unguent') [1] is the molten or semi-molten natural material from which all igneous rocks are formed. [2] Magma (sometimes colloquially but incorrectly referred to as lava) is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial ...

  8. Igneous rock - Wikipedia

    en.wikipedia.org/wiki/Igneous_rock

    Igneous rock (igneous from Latin igneus 'fiery'), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet 's mantle or crust.

  9. Upper mantle - Wikipedia

    en.wikipedia.org/wiki/Upper_mantle

    The upper mantle of Earth is a very thick layer of rock inside the planet, which begins just beneath the crust (at about 10 km (6.2 mi) under the oceans and about 35 km (22 mi) under the continents) and ends at the top of the lower mantle at 670 km (420 mi). Temperatures range from approximately 500 K (227 °C; 440 °F) at the upper boundary ...