What are the 2 types of igneous rocks? The two main categories of igneous rocks are extrusive and intrusive. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from
A nonconformity exists between sedimentary rocks and metamorphic or igneous rocks when thesedimentary rock lies above and was deposited on the pre-existing and eroded metamorphicor igneous rock. How are Disconformities formed? A disconformity is an unconformity between parallel layers of sedimentary ...
Rocks are classified according to characteristics such asmineral and chemical composition, permeability, texture of the constituent particles, and particle size. ... This transformation produces three general classes of rock: igneous, sedimentary and metamorphic. What do geologists use to study different ...