I Type Granite Formation

Amphibole and pyroxene are more common in i type granitoids while s type granitoids may have garnet cordierite and sillimanite.

I type granite formation.

This type of rock dominates the landscape in the yosemite high country near tuolumne meadows. These result in i type granitoids derived from igneous protoliths and containing moderate amounts of al 2 o 3 and high amounts of na 2 o and s type granitoids derived from sedimentary protoliths and containing high amounts of al 2 o 3 and relatively low amounts of na 2 o. Granite is composed mainly of quartz and feldspar with minor amounts of mica amphiboles and other minerals this mineral composition usually gives granite a red pink gray or white color with dark mineral. Granites can be predominantly white pink or gray in color depending on their mineralogy the word granite comes from the latin granum a grain in reference to the coarse grained structure of such a completely crystalline rock.

Granite is an intrusive igneous rock which means it was formed in place during the cooling of molten rock generally the slower the molten rock cooled the larger it s mineral crystals with k feldspar megacrysts forming in special circumstances greater than 5cm. Granite is most often formed where oceanic plates dive beneath continental plates in tectonic environments called subduction zones. Granite is a light colored igneous rock with grains large enough to be visible with the unaided eye. Granite ˈ ɡ r æ n ɪ t is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture.

High amounts of na2o and s type granitoids derived from sedimentary protoliths and containing high amounts of al2o3 and relatively low amounts of na2o. It forms from the slow crystallization of magma below earth s surface.