This is a preview. Log in through your library . Abstract Twelve of the more recent proposals for the classification of igneous rocks are discussed with the intention of noting points of agreement and ...

THE closing years of the nineteenth century witnessed a revival of interest in the petrology of gneous rocks, which must be regarded as marking an important stage in the development of that subject.

Igneous rocks close igneous rockIgneous rocks are those which have been formed by the cooling and solidification of molten rock (magma) from underneath the earth’s crust. are formed by magma from the ...