2.2 Three Classes of Rocks: Igneous, Sedimentary, and Metamorphic

1. 2.2 Three Classes of Rocks: Igneous, Sedimentary, and Metamorphic

2. Igneous Rocks – rocks that form from hot, molten rock • Ex. Obsidian, pumice, pegmatite, and basalt

3. Igneouos Rock

4. Intrusive Rock – igneous rocks formed from the magma that cooled and hardened beneath Earth’s surface • Extrusive Rock – igneous rocs that were formed from lava cooling on Earth’s surface.

5. Sedimentary Rock – layers of rocks that form when small pieces of rock carried by water or wind and settle or sink down in water onto the rocks below them. • Ex. Limestone, shale, conglomerate, and sandstone

6. Sedimentary Rock

7. Metamorphic Rock – rocks that have been changed because of intense pressure and heat within Earth’s interior • Ex. Gneiss, marble, schist, quartzite, and slate

8. Metamorphic Rock

9. Classifying – grouping of objects or events that have the same characteristics. • Remote Sensing – mapping of Earth’s surface from aircraft or orbiting satellites • Geophysical Prospecting – using sensitive instruments to detect mineral deposits hidden deep underground

10. Geochemcial Prospecting – making chemical analysis of samples taken from the environment. • Exploration – drilling holes to verify an ore body’s existence