General Science. What is an Earthquake?. Earthquakes are one of the most powerful natural forces Shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activity. Who Studies Earthquakes?. Seismologist study earthquakes
The following animation shows a bird's eye view of a country road that cuts through an orchard. Passing right down the middle of the orchard, and across the road, is a fault zone. The animation shows how the earth is gradually distorted about the fault, in response to distant forces, eventually leading to sudden slip or displacement along the fault--what we call an earthquake.
Located by the US Geological Survey National Earthquake Information Center