EPS 80 Lecture 2: EPS 80 Lecture Notes 9/6/2016
21 Sep 2016
School
Department
Course
Professor
Document Summary
Definition-a sudden shaking motion of the ground( in or on the earth"s surface) caused by the propagation of energy- as seismic waves- through the earth. Subduction zone earthquakes- japan- spread along dipping plate. Intraplate earthquakes- caused by plate motion but not near plate boundaries. Fault= a~ planar surface across which significant movement has occurred. As magma rises up in the earth, it forces its way through the rocks by going through small crevices, essentially making space. More earthquakes now because the earth is heating up and therefore more glaciers are moving. Get lots of gas and waste waters from the earth pumping water back into the earth. Faults are bounded by brittle rocks near surface ductile rocks (gooey) at depth. Usually only part of a fault moves at one time. Bigger faults make bigger earthquakes, higher magnitude=longer time span. Foreshock- eq that occurs before the main event (can last week, years, decades) Aftershock- eq that occur after the main event.
