Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry

W. Thatcher; D. Massonnet

doi:10.1029/97gl02597

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Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry

W. Thatcher·D. Massonnet

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Abstract

Satellite radar interferometric images of Long Valley caldera show a pattern of surface deformation that resembles that expected from analysis of an extensive suite of ground-based geodetic data. Images from 2 and 4 year intervals respectively, are consistent with uniform movement rates determined from leveling surveys. Synthetic interferograms generated from ellipsoidal-inclusion source models based on inversion of the ground-based data show generally good agreement with the observed images. Two interferograms show evidence for a magmatic source southwest of the caldera in a region not covered by ground measurements. Poorer image quality in the 4 year interferogram indicates that temporal decorrelation of surface radar reflectors is progressively degrading the fringe pattern in the Long Valley region.

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BibTeX RIS

W. Thatcher, D. Massonnet. 1997-10-15. Crustal deformation at long Valley Caldera, eastern California, 1992-1996 inferred from satellite radar interferometry. https://doi.org/10.1029/97gl02597

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