GENERAL GEOLOGY

Detailed explanation-1: -Intrusive, or plutonic, igneous rock forms when magma is trapped deep inside the Earth. Great globs of molten rock rise toward the surface.

Detailed explanation-2: -Igneous rocks that form below the Earth’s surface are called intrusive igneous rocks (or plutonic). They form when magma enters an underground chamber, cools very slowly because they are underground and do not reach the cool surface of the Earth.

Detailed explanation-3: -Intrusive (Plutonic) Rocks Intrusive igneous rocks solidify within Earth. These rocks are also known as plutonic rocks-named for Pluto, the Greek god of the underworld. Intrusive igneous rocks are generally wholly crystalline and characterized by large crystal sizes visible to the naked eye because they cool slowly.

Detailed explanation-4: -These are called intrusive igneous rocks because the magma has intruded into pre-exiting rock layers. Types of intrusive igneous rocks are granite and basalt.