Igneous rocks: Diorite Essay

Diorite is an igneous rock form from the partial melting of the crust caused from by basaltic magma from the mantle. It is associated with batholiths, dikes and stocks usually around volcanic arcs. Its volcanic equivalent is andesite which is formed from strombolian type volcanoes.DISCUSSIONPhysical propertiesDiorite is a phaneritic rock that is speckled inkiness and white/grey with a very variable colour top executive of between 40 and 90 over short distances. The rock has an equigranular or porphyritic texture and has a generally coarse grain size of it but can be pegmatitic. Phenocrysts of feldspar and horneblende can be order in the porphyritic variety. The equigranular and porphyritic varieties may vary in texture between each other within a few centimetres. A foliated appearance can develop from the roughly parallel coalition of the minerals.The rock has an intermediate composition between plagioclase feldspar (oligoclase or andesine) and amphibole (usually hornblende) wi th various other minor minerals like pyroxene, biotite. Quartz and alkali feldspar may also be present. When the amount of lechatelierite increases, the rock is named quartz diorite. The rock grades into granodiorite as the amount of quartz and alkali feldspar increases. radical feldspar increase. Some common accessory minerals are apatite, titanite and various beseech oxides.Xenoliths from the partially melted margins of the magma chamber are common.OriginDiorite usually forms on with granite in continental crust abovesubduction zones.