Tag «mineral composition of intermediate igneous rocks»

Chemical Composition of Igneous Rocks

Igneous rocks make approximately 90% of the earth’s crust by volume. But their great abundance is hidden on the earth’s surface by a relatively thin layer of sedimentary and metamorphic rocks. Igneous rocks are formed by the cooling and solidification of magma. Magma is a hot viscous, siliceous melt containing water vapour and gases. It …