ABSTRACT
This chapter provides a basic grounding in the principles of geology and explains how to apply them. Civilization exists by geological consent, subject to change without notice. Earthquakes raise mountains a few centimeters at a time over millions of years. Flash floods shape desert and mountain landscapes even though they occur once a decade/once a century. Explosive volcanic eruptions happen on a time scale of tens of thousands to hundreds of thousands of years. Active tectonic zones are the most likely places for earthquakes. Earthquakes occur suddenly and seemingly at random. Volcanoes affect people when they explode, when they erupt lava, and when they spew ash and gas. River flooding of agricultural lowlands are among the worst natural disasters in history. Natural subsidence is a slow process but rarely causes death. Sinkholes are caused by slightly acid rainwater slowly dissolving away underground limestone. Pollution is the presence of substances that are unsafe or harmful or poisonous to the environment.
