Publication Date:
2004-06-26
Description:
High-resolution interferometric synthetic aperture radar (InSAR) permanent scatterer data allow us to resolve the rates and variations in the rates of slow-moving landslides. Satellite-to-ground distances (range changes) on landslides increase at rates of 5 to 7 millimeters per year, indicating average downslope sliding velocities from 27 to 38 millimeters per year. Time-series analysis shows that displacement occurs mainly during the high-precipitation season; during the 1997-1998 El Nino event, rates of range change increased to as much as 11 millimeters per year. The observed nonlinear relationship of creep and precipitation rates suggests that increased pore fluid pressures within the shallow subsurface may initiate and accelerate these features. Changes in the slope of a hill resulting from increases in the pore pressure and lithostatic stress gradients may then lead to landslides.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hilley, George E -- Burgmann, Roland -- Ferretti, Alessandro -- Novali, Fabrizio -- Rocca, Fabio -- New York, N.Y. -- Science. 2004 Jun 25;304(5679):1952-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Earth and Planetary Science and Berkeley Seismological Laboratory, University of California, Berkeley, CA 94720, USA. hilley@seismo.berkeley.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15218146" 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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