ABSTRACT
Mountains are lithic entities, composed of a diversity of rock and minerals. These massive structures are compressed, folded, faulted, heated, layered, melted, shaped, sheared, twisted, and uplifted by their sheer pressure and weight as the tectonic plates under them move. Some types of rocks discussed in this chapter are: igneous, metamorphic and sedimentary rocks. Planetary geologic forces constantly are making and breaking down rock. Igneous rock can change into either metamorphic rock or sedimentary rock. And, finally, sedimentary rock can change into igneous rock or metamorphic rock. Volcanic activity often results in mountain building. The sudden and extreme movement of an earthquake influences mountain building and contributes to mountain weathering. Earthquakes are a regular part of plate tectonics and occur almost constantly around the world. Once tectonic activity or a volcanic episode ceases, the main geologic event becomes weathering. The rate of weathering is impacted by several factors, including elevation, erosion, climate, glaciers, and mass movement.
