Abstract
An imaginary empirical law to relate earthquake magnitude, M, hypocentral distance, R, and the amount of expected static deformation of the Earth's surface was derived by a simulation using the Monte Carlo method. Assuming a point double couple for each of a million seismic sources, the frequency distributions of displacement, strain and tilt were examined. The results are summarized as follows: 1) Expected maximum values of crustal deformation can be expressed by logUmax=1.5M-2logR(km)-6.0 for static displacement, U(cm), logFmax=1.5M-3logR(km)-10.7 for static strain and tilt, F. 2) Expected average values of crustal deformation are 1/3-1/4 of the expected maximum values stated above. 3) The whole distributions of deformation are confined within relatively narrow ranges, and most are between the maxima and 1/10 of the averages. Although the above results can be used only for rough estimation, the obtained empirical law is useful not only for designing an observation network of crustal deformation but also for evaluation of the influences of seismic events.
