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Earthquake repeat time and average stress drop

Kanamori, Hiroo and Allen, Clarence R. (1986) Earthquake repeat time and average stress drop. In: Earthquake Source Mechanics. Geophysical monograph. No.37. American Geophysical Union , Washington, DC, pp. 227-235. ISBN 9780875904054.

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Existing data on source parameters of large crustal earthquakes (subduction events are not considered here) over a wide range of repeat times indicate that, for a given magnitude (M_s or M_w), earthquakes with long repeat times have shorter fault lengths than those with short repeat times. A shorter fault length for a given magnitude indicates a larger average stress drop which reflects the average strength of the fault zone. Our result therefore suggests that faults with longer repeat times are stronger than those with shorter repeat times. In terms of an asperity model in which the average strength of a fault zone is determined by the ratio, r_a, of the total area of the asperities (strong spots on a fault plane) to the total area of the fault zone, the above result suggests that r_a is proportional to the repeat time. Our result provides a method to estimate seismic source spectra from the fault length and the repeat time of a potential causative fault.

Item Type:Book Section
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Kanamori, Hiroo0000-0001-8219-9428
Additional Information:© 1986 American Geophysical Union. Published Online: 18 MAR 2013. Published Print: 1 JAN 1986. We thank T. Heaton, S. Honda, T. Matsuda, J. Pechmann, David Schwartz, K. Sieh, and S. Wesnousky for discussion and comments on the manuscript. This research was partially supported by U. S. Geological Survey contracts 14-08-0001-G-979 and 14-08-0001-21981. Contribution number 4245, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125.
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Subject Keywords:Faults (Geology), Earthquakes
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Caltech Division of Geological and Planetary Sciences4245
Series Name:Geophysical monograph
Issue or Number:37
Record Number:CaltechAUTHORS:20141016-130549566
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Official Citation:Kanamori, H. and Allen, C. R. (1986) Earthquake Repeat Time and Average Stress Drop, in Earthquake Source Mechanics (eds S. Das, J. Boatwright and C. H. Scholz), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM037p0227
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:50452
Deposited By: Tony Diaz
Deposited On:16 Oct 2014 22:33
Last Modified:10 Nov 2021 18:56

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