| Abstract: | We use the energy-to-moment ratio, as introduced by Newman and Okal [1998] to examine the source characteristics of normal-faulting intraslab earthquakes, compared to nearby interplate thrust events, based on recent case studies in central Chile and southeastern Mexico. In Chile, we find that the 1997 intraslab event had an exceptionally large E/M0 ratio, 30 times greater than the nearby interplate shock. This suggests a very fast strain release at the source as the origin of the particularly destructive character of intraslab events. While the difference is less sharp in Mexico, we find a similar trend, which is in agreement with the observation that the locally most damaging earthquakes are indeed the intraslab events. We also document on the 1939 Chilean earthquake the feasibility
of extending this approach to historical earthquakes for which high-quality analog records have been archived. |
| Genre: | USGS Numbered Series |
| ProdID: | 50381 |
| Citation Author: | Okal, Emile A.; Kirby, S. H. |
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| Citation Edition: | - |
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| Citation End Page: | 121 |
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| Citation Language: | ENGLISH |
| Citation Larger Work Title: | USGS Numbered Series Title The Cascadia Subduction Zone and related subduction systems; seismic structure, intraslab earthquakes and processes, and earthquake hazards |
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| Citation Number Of Pages: | 5 |
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| Citation Phsyical Description: | pp. 117-121 |
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| Citation Publisher: | U.S. Geological Survey |
| Citation Series: | Open-File Report |
| Citation Series Code: | OFR |
| Citation Series Number: | 2002-328 |
| Citation Search Results Text: | Energy-to-moment ratios for damaging intraslab earthquakes: Preliminary results on a few case studies; 2001; OFR; 2002-328; USGS Numbered Series Title The Cascadia Subduction Zone and related subduction systems; seismic structure, intraslab earthquakes and processes, and earthquake hazards; Okal, Emile A.; Kirby, S. H. |
| Citation Start Page: | 117 |
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| Citation Year: | 2001 |
| Type: | citation/reference |
| Text: | Energy-to-moment ratios for damaging intraslab earthquakes: Preliminary results on a few case studies; 2001; OFR; 2002-328; USGS Numbered Series Title The Cascadia Subduction Zone and related subduction systems; seismic structure, intraslab earthquakes and processes, and earthquake hazards; Okal, Emile A.; Kirby, S. H. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/usgs_thumb.jpg |
| URL (INDEX PAGE): | http://geopubs.wr.usgs.gov/open-file/of02-328/ |
| Date Other: | Tue, 1 Jan 2002 15:23 -0600 |
| Publisher: | U.S. Geological Survey |
