The calculated location of the focus of an earthquake. Isoseismal Line A line connecting points on the Earth's surface at which earthquake intensity is the same. It is usually a closed curve around the epicenter. Landslide An abrupt movement of soil and bedrock downhill in response to gravity. Landslides can be triggered by an earthquake or other natural causes.
Undersea landslides can cause tsunamis.
Latitude The location of a point north or south of the equator. Latitude is shown on a map or globe as east-west lines parallel to the equator. A surface seismic wave which is imperfectly trapped so that its energy leaks or escapes across a layer boundary causing some attenuation, or loss of energy. In other words, solid ground turns to jelly. A surface wave which travels through the continental crust.