CRUSTAL DEFORMATION AT LONG VALLEY CALDERA, EASTERN CALIFORNIA, 1992-1996 INFERRED FROM SATELLITE RADAR INTERFEROMETRY

Satellite radar interferometric images of Long Valley caldera show a p attern of surface deformation that resembles that expected from analys is 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 gene rated from ellipsoidal-inclusion source models based on inversion of t he ground-based data show generally good agreement with the observed i mages. Two interferograms show evidence for a magmatic source southwes t of the caldera in a region not covered by ground measurements. Poore r image quality in the 4 year interferogram indicates that temporal de correlation of surface radar reflectors is progressively degrading the fringe pattern in the Long Valley region.