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Felsic. In geology, felsic is a modifier describing igneous rocks that are relatively rich in elements that form feldspar and quartz. [1] It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen ...
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 ...
The thin parts are the oceanic crust, which underlie the ocean basins (5–10 km) and is mafic-rich [9] (dense iron-magnesium silicate mineral or igneous rock). [10] The thicker crust is the continental crust, which is less dense [11] and is felsic-rich (igneous rocks rich in elements that form feldspar and quartz). [12]
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.
Magmatism along strike-slip faults is the process of rock melting, magma ascent and emplacement, associated with the tectonics and geometry of various strike-slip settings, most commonly occurring along transform boundaries at mid-ocean ridge spreading centres [1] and at strike-slip systems parallel to oblique subduction zones. [2]
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 ...
Show comments. There was once a magma-filled ocean on the south pole of the moon, scientists recently discovered after analyzing lunar soil that revealed ancient information about the moon's ...
Intraplate volcanism is volcanism that takes place away from the margins of tectonic plates. Most volcanic activity takes place on plate margins, and there is broad consensus among geologists that this activity is explained well by the theory of plate tectonics. However, the origins of volcanic activity within plates remains controversial.