Abstract Title: Passive Teleseismic Imaging of Extensional Processes and 
Small-Scale Convection

Abstract Author(s): Aster, R. - Wilson, D. (New Mexico Tech) - West, M. - Ni, 
J. (New Mexico State University) - Grand, S. - Gao, W. (University of Texas, 
Austin) - Baldridge, W.S. (Los Alamos National Laboratory) - Semken, S. 
(Arizona State University)  

Abstract: Seismic imaging of crust and mantle underlying the Great Basin, and 
relating these images to the region's dramatic recent extensional history, will 
be a key component of EarthScope efforts during the next five years and beyond. 
One analog experiment is RISTRA, a dense (18-km station spacing) PASSCAL 
experiment deployed in 1999-2001. RISTRA transected the western Great Plains, 
the Rio Grande Rift, and extended into the interior Colorado Plateau. The 
project revealed new details on rift extension and fine-scale upper mantle 
discontinuity and velocity structure. Experiment details, processing 
techniques, and results pertaining to the extensional and convective processes 
underlying RISTRA will be summarized and related to targets of scientific 
interest in the Great Basin region.