HOW DOES MAGMA CRYSTALLIZE?
Crystals don’t all form at once. Some form at high temperature, and others form later as the magma cools. Low silica minerals crystallize first (at highest temperature). The approximate order of crystallization, which varies with composition, H2O and pressure, is BOWEN’S REACTION SERIES Discontinuous Series………….Continuous Series olivine Ca-plagioclase pyroxene (augite) Na-plagioclase amphibole (hornblende) biotite mica K- feldspar muscovite mica quartz MINERALS MAKE THE ROCK Which minerals are present in the rock depends on the composition of the magma from which they formed. Ultramafic rocks form today only in the mantle. Peridotite is made of Mafic magma forms gabbro and basalt. The minerals in basalt and gabbro are: Intermediate magma forms diorite and andesite. The minerals in diorite and andesite are: Felsic magma forms granite and rhyolite. The minerals in granite and rhyolite are: WHERE DOES MAGMA FORM? Magma forms in both the mantle and crust. Magma forms in various tec
