HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) References Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Humphrey, J. R. Articles by Anderson, J. G. Search for Related Content GeoRef GeoRef Citation

Seismic source parameters from the Guerrero subduction zone

Seismological Laboratory and Department of Geological Sciences Mackay School of Mines University of Nevada-Reno, Reno, Nevada 89557-0047

Abstract

A method to systematically determine seismic moment and corner frequency from shear-wave spectra has been applied to strong-motion data recorded in Guerrero, Mexico. The method determines a model spectrum that minimizes the misfit from the observed spectrum, after a correction for frequency-dependent site response has been applied. The calculated moments for larger events in Guerrero are consistent with moments determined from teleseismic body waves adjusted for differences in focal depth and consequent assumed differences in the velocity and density structure in the source region. The average stress drop for the 82 earthquakes with magnitudes from 3 to 7 is 150 bars. The spatial distribution of the stress drops shows a distinctive pattern. At the northwest end of the Guerrero gap, adjacent to the aftershock zones of large earthquakes in 1979 and 1985, there is a mix of low- and high-stress-drop events. At the southeast end of the Guerrero gap, where the most recent large earthquake occurred in 1957, there are predominantly high-stress-drop events. This pattern might be caused by the different relative positions of these two active regions in the earthquake cycle, although several other explanations cannot be ruled out.

This article has been cited by other articles:

				J. Aguirre and K. Irikura Source Characterization of Mexican Subduction Earthquakes from Acceleration Source Spectra for the Prediction of Strong Ground Motions Bulletin of the Seismological Society of America, December 1, 2007; 97(6): 1960 - 1969. [Abstract] [Full Text] [PDF]

				G. Tusa, A. Brancato, and S. Gresta Source Parameters of Microearthquakes in Southeastern Sicily, Italy Bulletin of the Seismological Society of America, June 1, 2006; 96(3): 968 - 983. [Abstract] [Full Text] [PDF]

				A Comprehensive Study of the Observed Spectral Decay in Strong-Motion Accelerations Recorded in Guerrero, Mexico Bulletin of the Seismological Society of America, April 1, 2003; 93(2): 600 - 611.

				J. G. Anderson Expected Shape of Regressions for Ground-Motion Parameters on Rock Bulletin of the Seismological Society of America, December 1, 2000; 90(6B): S43 - S52. [Abstract] [Full Text] [PDF]

				Source Time Function and Duration of Mexican Earthquakes Bulletin of the Seismological Society of America, April 1, 2000; 90(2): 468 - 482.

				L. Quintanar, J. Yamamoto, and Z. Jimenez Source mechanism of two 1994 intermediate-depth-focus earthquakes in Guerrero, Mexico Bulletin of the Seismological Society of America, August 1, 1999; 89(4): 1004 - 1018. [Abstract] [PDF]

				J. G. Anderson and Q. Chen Beginnings of earthquakes in the Mexican subduction zone on strong-motion accelerograms Bulletin of the Seismological Society of America, August 1, 1995; 85(4): 1107 - 1115. [Abstract] [PDF]