1.1 Extrusive Rocks Extrusive rocks are those rocks which have are ejected from a volcano or some other vent and are accumulated and solidified on the surface of the earth. These rocks may be further subdivided into two parts on the basis of the way of eruption. Learn the types of rocks and their formation. Understand key geology terms in simple words to improve your English vocabulary and knowledge. Rocks are commonly divided into three major classes according to the processes that resulted in their formation. A rock is a solid combination of minerals. The earth’s crust is made up of rocks that are different from one another in texture, structure, colour, permeability, mode of occurrence, and degree of resistance to denudation. Feldspar and quartz are the most common minerals found in rock. There are three main types of rocks : igneous, sedimentary, and metamorphic rocks . In this article, we will learn about types of rocks which is part of Geomorphology, an integral part of the Geography Syllabus.
