Publication Date:
2003-04-05
Description:
Borehole data from young sediments folded above the Puente Hills blind thrust fault beneath Los Angeles reveal that the folding extends to the surface as a discrete zone (〈/=145 meters wide). Buried fold scarps within an upward- narrowing zone of deformation, which extends from the upward termination of the thrust ramp at 3 kilometers depth to the surface, document the occurrence of at least four large (moment-magnitude 7.2 to 7.5) earthquakes on this fault during the past 11,000 years. Future events of this type pose a seismic hazard to metropolitan Los Angeles. Moreover, the methods developed in this study can be used to refine seismic hazard assessments of blind thrusts in other metropolitan regions.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dolan, James F -- Christofferson, Shari A -- Shaw, John H -- New York, N.Y. -- Science. 2003 Apr 4;300(5616):115-8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089-0740, USA. dolan@earth.usc.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12677063" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
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Computer Science
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Medicine
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Natural Sciences in General
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Physics
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