See text, p. 94. Note great abundance of silicate minerals. Read p. 97, text. See text, p. 96. Rocks Rock types and rock distribution .
Metamorphic rocks come in a poor third.
Thus igneous rocks are found in association with the mobile zones of the earth's crust - past or present, such as plate boundaries, centers of mountain ranges, floor of the oceans, etc. Read about plate tectonics in your text, p. 102-110. Also, know which types of igneous rocks for in different plate tectonic settings. What are examples of these types of ign. Many building materials and ornamental rock facings are constructed of ign.