Evaluating Temporal Variations in Fault Slip-Rate and Fault Interaction in the Eastern California shear zone

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This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Dr. Colin Amos has been granted an NSF Earth Sciences postdoctoral fellowship to develop an integrated program of research and education at the University of California, Berkeley. The project will quantify active deformation at multiple geologic timescales for faults in Eastern California. The Little Lake fault, one of the primary structures in eastern California responsible for transferring Pacific-North American plate motion will be the focus of this study. A series of lava flows and dry river channels incised by the ancient Owens Lake drainage system is displaced by the Little Lake fault and permits reconstruction of past fault movements at timescales of ~10,000-100,000 years. Reconstruction of the Late Quaternary ? Holocene record of slip on this fault zone will involve: 1) characterization of offset landforms through geomorphic and neotectonic mapping, 2) quantification of fault displacements with high-resolution topographic surveying, and 3) establishing chronologic constraints through cosmogenic radionuclide dating. This reconstruction will provide the first direct comparison with high rates of geodetically measured strain along the Little Lake fault and will elucidate the degree to which strain transients may modulate fault slip and earthquake activity within the Eastern California shear zone. The results of this work will be incorporated into laboratory exercises as part of a larger introductory field geology course aimed at reaching non-science majors at UC Berkeley. Additionally, a series of public, scientific lectures will be presented at the UC White Mountain Research Station in Bishop, CA. These lectures will serve as a vehicle for raising awareness and disseminating information on the local seismic hazards to community members and policy makers at direct risk from earthquakes in the Eastern California shear zone.