Spatial variations in slip rate along the Death Valley‐Fish Lake Valley fault system determined from LiDAR topographic data and cosmogenic 10Be geochronology

Abstract

The Death Valley‐Fish Lake Valley fault zone (DV‐FLVFZ) is a prominent dextral fault system in the eastern California shear zone (ECSZ). Combining offset measurements determined with LiDAR topographic data for two alluvial fans with terrestrial cosmogenic nuclide 10Be ages from the fan surfaces yields a late Pleistocene slip rate of ∼2.5 to 3 mm/yr for the northern part of the DV‐FLVFZ in Fish Lake Valley. These rates are slower than the late Pleistocene rate determined for the system in northern Death Valley, indicating that slip rates decrease northward along this major fault zone. When summed with the slip rate from the White Mountains fault, the other major fault in this part of the ECSZ, our results suggest that either significant deformation is accommodated on structures east of Fish Lake Valley, or that rates of seismic strain accumulation and release have not remained constant over late Pleistocene to Holocene time.