9316889 Bock The PI and his postdoctoral associate will analyze their 1992 and 1993 GPS regional measurements from Sumatra and other islands in the Indonesian archipelago to study crustal deformation along the Sumatran fault and the forearc region to the southwest. Continuous improvements in GPS satellite constellation, receiver technology and global tracking networks permit significantly more accurate estimates of surface deformation for these two years than for any of the preceding three years. In this way, they can assess qualitatively and quantitatively the decoupling of oblique slip along this plate margin into normal subduction and shear slip. They will also analyze repeated GPS measurements collected from 1990 through 1993 along five fault transects. These small scale linear arrays complement the regional network by providing a detailed picture of the near-fault strain field at various fault segments. ****
