Rupture processes of the 1987–1988 Gulf of Alaska Earthquake Sequence
- Creators
- Hwang, Lorraine J.
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Kanamori, Hiroo
Abstract
Three large earthquakes occurred in the Gulf of Alaska during 1987–1988: one on November 17, 1987 (M_w = 7.2), the second one on November 30, 1987 (M_w = 7.8), and the third one on March 6, 1988 (Mw = 7.7). These major intraplate, strike-slip oceanic events occurred along conjugate trends in a region of no previous seismicity. Body wave modeling places their centroid depths in the upper mantle. The depth of the first two events is approximately 20 km and of the third is 15 km. As compared to other large events, the body wave models for the two largest earthquakes have short rupture lengths, 110 km and 40 km, respectively, and short duration times, 36 and 20 s, respectively, for their magnitude. The latter of the two events has a rupture length much shorter than that inferred from aftershock seismicity. The short rupture lengths and source durations may reflect differences between the strength of oceanic and continental lithosphere and suggest that events in oceanic lithosphere have a higher moment release per unit area than similar continental events. Most of the moment release occurred near the epicenter and/or regions of apparent structural complexities where seismicity trends intersect.
Additional Information
Copyright 1992 by the American Geophysical Union. (Received June 7, 1991; revised July 20, 1992; accepted July 23, 1992.) Paper number 92JB01817. We thank J. Lahr and C. Stephens for sharing their first motion data and aftershock relocations with us. Many thanks to Jeanne Sauber as well as several anonymous reviewers for their time and diligence in catching many of the egregious prethesis and postthesis errors and their suggestions which tremendously improved the presentation of this paper. This work was supported by an NSF Graduate Fellowship and the U.S. Geological Survey under contract 14-08-0001-G1170. This is contribution 5031 of the Division of Geological and Planetary Sciences, California Institute of Technology.Attached Files
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Additional details
- Eprint ID
- 50970
- Resolver ID
- CaltechAUTHORS:20141028-163948215
- NSF Graduate Research Fellowship
- USGS
- 14-08-0001-G1170
- Created
-
2014-10-28Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences (GPS)
- Other Numbering System Name
- Caltech Division of Geological and Planetary Sciences
- Other Numbering System Identifier
- 5031