Spatial and temporal evolution of intracontinental shear zones: The Stateline fault system, Eastern California Shear Zone (USA)

• Antragsteller: Professor Dr. Bernard Guest
• Fachliche Zuordnung: Paläontologie
• Förderung: Förderung von 2007 bis 2008
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 48513770

We propose a short-term preliminary study of the Stateline fault system, which lies on the California-Nevada border, USA. The basic aim of this project is to collect preliminary geologic, tectono-geomorphic and geophysical (small seismic survey) data along this fault system with the goal of producing a new tectono-geomorphic map for this fault zone and laying the ground work for a larger project focused on constraining lateral spatial and temporal gradients in slip-rate. We choose to focus on the Stateline fault because it s young deformation record was previously unrecognized and because, based on preliminary GPS data, it appears to lie within the eastern California shear zone, which forms the boundary region between the Pacific plate and stable North America. Its evolution relative to the rest of the eastern California shear zone, which account for approximately 25% of Pacific-North America plate motion, is therefore important to our understanding of the factors governing processes like continental shear zone deformation and propagation. This area is also important because it is seismically active and includes several large population centers (e.g. Las Vegas) and the largest proposed high-level nuclear waste storage facility in North America (Yucca Mountain). We plan to do the following during the 2007 field season (February through May): 1. Map critical exposed segments of the fault zone in detail (1:10,000 to 1:5,000 scale) to identify fault segments that have ruptured recently and to sample these segments in order to establish timing constraints for the rupture events. 2. Conduct a seismic survey across the fault system in several key locations to constrain the fault zone width and geometry. 3. To identify promising trench sites for the next phase of work on this fault zone in order to determine the space time patterns of past earthquake ruptures, and a longer term slip rate on the fault (future DFG proposal).

• DFG-Verfahren: Sachbeihilfen
• Beteiligte Person: Professorin Anke Friedrich, Ph.D.