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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. Komatiite - Wikipedia

    en.wikipedia.org/wiki/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.

  4. Magmatism - Wikipedia

    en.wikipedia.org/wiki/Magmatism

    As tectonic plates move relative to a hotspot, the location of magmatic activity on the plate shifts, causing the development of time-progressive chains of volcanoes such as the Hawaiian–Emperor seamount chain. The main product of hotspot volcanoes are Ocean Island Basalts (OIB), which are distinct from MORB and IAB type basalts.

  5. Magma - Wikipedia

    en.wikipedia.org/wiki/Magma

    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 planets and some natural satellites. [3] Besides molten rock, magma may also contain suspended crystals and gas bubbles.

  6. Oceanic crust - Wikipedia

    en.wikipedia.org/wiki/Oceanic_crust

    The lines represent tectonic plate boundaries. Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. [1][2] The crust overlies the rigid uppermost ...

  7. Ultrapotassic igneous rocks - Wikipedia

    en.wikipedia.org/wiki/Ultrapotassic_igneous_rocks

    Ultrapotassic igneous rocks. Ultrapotassic igneous rocks are a class of rare, volumetrically minor, generally ultramafic or mafic silica-depleted igneous rocks. While there are debates on the exact classifications of ultrapotassic rocks, they are defined by using the chemical screens K 2 O/Na 2 O > 3 in much of the scientific literature. [1]

  8. 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 ...

  9. 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.