Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published 1965 | public
Book Section - Chapter

Dimensions of the Source Region for Small Shallow Earthquakes

Press, Frank

Abstract

The dimensions of the source of small-magnitude earthquakes can be inferred from: (1) Spectrum as a function of magnitude (2) Fault length as a function of magnitude (3) Dimension of explosion sources having the same magnitude and spectrum (4) Strain-energy considerations. Available data are reviewed and interpreted to obtain very rough indications of the source dimension for small- magnitude earthquakes. A magnitude 4 earthquake may have a source dimension between 1/10 and 1 km. Tocher's hypothesis on a plastic zone within the crust is modified to place the zone in the upper-mantle low-velocity, low-Q region. With this change, energy release from large earthquakes would vary with the horizontal area of the source region. Small earthquakes would release energy proportional to the volume of the source region.

Additional Information

© 1965 University of Michigan. Contribution 1324, Division of Geological Sciences, California Institute of Technology, Pasadena. This research was supported by the Advanced Research Projects Agency and was monitored by the Air Force Office of Scientific Research under Contract AF 49(638)-1337.

Additional details

Created:
August 19, 2023
Modified:
October 20, 2023