Earthquakes are the result of plate tectonics, or shifting plates in the crust of Earth, and quakes occur when the frictional stress of gliding plate boundaries builds and causes failure at a fault line. In an earthquake, elastic strain energy is released and waves radiate, shaking the ground. Scientists can predict where major temblors might occur in a general sense, but research does not yet allow forecasts for specific locations or accurate predictions of timing. Major earthquakes, some generating tsunamis, have leveled entire cities and affected whole countries. Relatively minor earthquakes can also be induced, or caused by human activity, including extraction of minerals from Earth and the collapse of large buildings.
From the eruption that buried Pompeii in A.D. 79 to the superstorm that shut down New York City in 2012, natural disasters are an unavoidable part of life on Earth. Once thought to be the wrath of the gods, these formidable events now have widely accepted
From earthquakes to volcanic eruptions to hurricanes, natural disasters reveal the fearsome power of Mother Nature. Scientists are studying these phenomena to better understand them and find better ways to predict and prepare for them.
Oct. 17 marks the 25th anniversary of the 1989 Loma Prieta earthquake. The animation shows earthquake waves speed away from the epicenter in the Santa Cruz Mountains south of San Francisco, California.