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Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Felsic magma or lava is higher in viscosity than mafic magma/lava, and have low temperatures to keep the felsic minerals molten. Felsic rocks are usually light in color and have specific ...
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation of LIPs is variously attributed to mantle plumes or to processes associated with divergent plate ...
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 ...
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.
Felsic eruption forms felsic volcanic rocks near the volcano and a spectrum of volcano-sedimentary sequence in the sea in Archean. [1] Archean felsic volcanic rocks are felsic volcanic rocks that were formed in the Archean Eon (4 to 2.5 billion years ago). [2] The term "felsic" means that the rocks have silica content of 62–78%. [3]
Earth's crustal evolution. Surface map of oceanic crust showing the generation of younger (red) crust and eventual destruction of older (blue) crust. This demonstrates the crustal spatial evolution at the Earth's surface dictated by plate tectonics. Earth's crustal evolution involves the formation, destruction and renewal of the rocky outer ...
Peridotite. Peridotite (US: / ˈpɛrɪdoʊˌtaɪt, pəˈrɪdə -/ PERR-ih-doh-tyte, pə-RID-ə-) is a dense, coarse-grained igneous rock consisting mostly of the silicate minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium (Mg 2+), reflecting the high proportions of ...
Petrology. Gabbro is a coarse-grained (phaneritic) igneous rock that is relatively low in silica and rich in iron, magnesium, and calcium. Such rock is described as mafic. Gabbro is composed of pyroxene (mostly clinopyroxene) and calcium-rich plagioclase, with minor amounts of hornblende, olivine, orthopyroxene and accessory minerals. [4]