Faults are breaks in rock masses along which movement has occurred.
A fault zone can be identified by a thin band of crushed rock. The length of a fault may vary from a few centimeters to thousands of kilometers. Because we live in Southern Calfornia we are very much interested in learning as much as we can about the San Andrea Fault. You can use shuttle images and landsat images to identify faults breaking the surface of the earth. You can discover more about the faults in your own backyard.