MAGMA TYPES CAN BE READ IN ROCK

A

In comparison with basalt, andesite consists of higher concentrations of silicon dioxide – between 52 and 63 %. The rock is based on intermediary magma, which is thicker than mafic magma.

B

The most viscous magma type hardens into rhyolite. The rock contains more than 63 % silicon dioxide in the shape of crystals known as quartz. The crystals are the secondmost common mineral on Earth's surface.