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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).
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.
Silverthrone is part of the Pemberton Volcanic Belt, which is circumscribed by a group of epizonal intrusions.At another deeply eroded caldera complex called Franklin Glacier Complex, the Pemberton Volcanic Belt merges with the Garibaldi Volcanic Belt, a northwest-trending belt of volcanic cones and fields extending from near the Canada–United States border east of Vancouver on the British ...
Caldera. A caldera (/ kɔːlˈdɛrə, kæl -/ [1] kawl-DERR-ə, kal-) is a large cauldron -like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly ...
Metamorphic rock can be formed locally when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior. The study of metamorphic rocks (now exposed at the Earth's surface following erosion and uplift) provides information about the temperatures and pressures that occur at great depths within the Earth's crust.
Earth's crustal evolution involves the formation, destruction and renewal of the rocky outer shell at that planet 's surface. The variation in composition within the Earth's crust is much greater than that of other terrestrial planets. Mars, Venus, Mercury and other planetary bodies have relatively quasi-uniform crusts unlike that of the Earth ...
The greenstone belts may be subsequently intruded by dome-shaped magma chambers. [19] The intrusion deformed the felsic volcanic rocks along with the volcano-sedimentary sequences. [5] Observing modern volcanic processes is relatively easier than observing Archean volcanism, because erosion constantly started removing earlier formed materials. [20]
The Bushveld Igneous Complex (BIC) is the largest layered igneous intrusion [1][2] within the Earth's crust. [3] It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin: the Transvaal Basin. It is approximately two billion years old [4] and is divided into four limbs: northern, eastern ...