Publication Date:
2001-11-17
Description:
Seismic reflection and refraction images illuminate the San Andreas Fault to a depth of 1 kilometer. The prestack depth-migrated reflection image contains near-vertical reflections aligned with the active fault trace. The fault is vertical in the upper 0.5 kilometer, then dips about 70 degrees to the southwest to at least 1 kilometer subsurface. This dip reconciles the difference between the computed locations of earthquakes and the surface fault trace. The seismic velocity cross section shows strong lateral variations. Relatively low velocity (10 to 30%), high electrical conductivity, and low density indicate a 1-kilometer-wide vertical wedge of porous sediment or fractured rock immediately southwest of the active fault trace.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hole, J A -- Catchings, R D -- St Clair, K C -- Rymer, M J -- Okaya, D A -- Carney, B J -- New York, N.Y. -- Science. 2001 Nov 16;294(5546):1513-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Geological Sciences, Virginia Tech, Blacksburg, VA 24061-0420, USA. hole@vt.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11711672" 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
,
Medicine
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Natural Sciences in General
,
Physics
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