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Faults and Earthquake Geology Active

By Earthquake Hazards Program March 6, 2019

To understand the risk that different areas of the U.S. face for earthquake hazards, we need to know where faults are and how they behave. We know a fault exists only if it has produced an earthquake or it has left a recognizable mark on the earth’s surface. Once a fault has been identified, the next step is to determine how it behaves.

To understand the risk that different areas of the U.S. face for earthquake hazards, we need to know where faults are and how they behave. We know a fault exists only if it has produced an earthquake or it has left a recognizable mark on the earth’s surface. Once a fault has been identified, the next step is to determine how it behaves.