Why Do Geologists Study Faults?
Active faults generate earthquakes. Geologists study them to better understand where and when future earthquakes will occur. Geologists study faults to better understand where large earthquakes originate. The Earth’s plates are constantly moving, but most faults are motionless, locked by friction, until the day when the force on the fault builds up enough to overcome the resistance. When that happens, the rocks on either side of the fault lurch into motion, releasing pent-up energy in an earthquake. Most earthquakes are so small that special instruments are needed to detect them, but a few release huge amounts of energy, causing widespread destruction. During most earthquakes, fault motion stays below the Earth’s surface, but in large earthquakes, fault motion may break through to the surface, offsetting rocks and sediments, as well as anything built on the fault, as much as ten feet or more. Earthquake shaking can cause widespread destruction, as is shown by newspaper drawings made af
