A tsunami is a series of huge waves generated by earthquakes or volcanic eruptions that can reach heights of 30 meters, travel as fast as jets, and go 1.25 miles inland. Mudslides are fast moving landslides of mud caused by heavy rain that destroy everything. Earthquakes are caused by movement of tectonic plates under the surface, with 4/5 occurring in the Pacific Rim. Avalanches are like mudslides but made of snow and ice occurring after fresh snowfalls in mountains traveling at 80 mph.