Experimental determination of earthquake fault length and rupture velocity

Three methods of determining the fault parameters of length and rupure velocity are examined with ultrasonic models. The theory behind the methods is shown to have a valid though approximate basis. Oversimplified assumptions and imperfect experimental data restrict initial results to only rough indications of fault parameters. When applied to the great Chilean earthquake of May 1960, a fault length of the order of 1000 km and a rupture velocity near the speed of shear waves in crustal rock are found.