Composition Of Granite And Basalt

Granite coarse or medium grained intrusive igneous rock that is rich in quartz and feldspar.

Composition of granite and basalt.

Basalt is mafic while granite is felsic basalt is common on both earth and other solar system bodies such as the moon and mars while granite is only common on earth and rare elsewhere in the solar system. Basalt is rich in iron and magnesium and is mainly composed of olivine pyroxene and plagioclase. Among other differences the nature of these rocks reveals that basalt is basic in nature whereas granite is acidic in nature. Granite cut and polished surface of granite magnified 1 5.

Of the two basalt is darker and consists of fine grained minerals such as magnesium and iron while granite is lighter and consist of feldspar and quartz. Most specimens are compact fine grained and glassy. This composition is as follows. Basalt is volcanic or extrusive forming at the surface while granite is plutonic or intrusive forming beneath the surface.

It is the most common plutonic rock of the earth s crust forming by the cooling of magma silicate melt at depth. They can also be porphyritic with phenocrysts of olivine augite or plagioclase. The granite field comprises two sub fields. The temperature of lava is between 1100 to 1250 c when it gets to the surface.

70 18 silicon dioxide sio2 14 47 aluminum oxide al2o3 4 11 potassium oxide k2o 3 48 sodium oxide na2o 1 99 calcium oxide cao 1 78 iron ii oxide feo 1 57 iron iii oxide 0 88 magnesium oxide mgo 0 84 water h2o 0 39 titanium dioxide tio2 0 19 diphosphorus pentoxide p2o5 and 0 12 manganese oxide mno. Holes left by gas bubbles can give basalt a coarsely porous texture. Rhyolite andesite and basalt form a series that varies in composition from felsic to mafic because of an increasing fraction of iron magnesium rich minerals that darkens the tone. Basalt is basic and contains a substantial amount of olivine whereas granite is acidic and is rich in quartz basalt is an extrusive igneous rock with small mineral crystals formed when magma cools.

Grant mason from the byu department of physics and astronomy discusses samples of granite and basalt rock.