Abstract
The Eastern California Shear Zone (ECSZ) accommodates approximately 20–25% of Pacific–North American relative plate motion, yet persistent discrepancies between geodetically inferred strain accumulation and Holocene-to-late Pleistocene geologic slip rates complicate regional seismic hazard evaluations. In this study, we utilize high-resolution airborne light detection and ranging (lidar) data (average point density ~12 points/m²) to construct 0.5 m bare-earth digital elevation models (DEMs) across active strike-slip and oblique-normal fault strands in the central Mojave and southern Walker Lane sections of the ECSZ. By extracting sub-meter topographic profiles, retro-deforming offset geomorphic markers (such as alluvial fan risers, incised channels, and debris-flow levees), and integrating published terrestrial cosmogenic nuclide (10Be and 26Al) exposure ages, we determine revised late Quaternary slip rates for the Blackwater, Calico, and Southern Panamint Valley fault systems. Our results yield late Pleistocene-to-Holocene horizontal slip rates of 1.9 ± 0.3 mm/yr for the Calico fault and 1.1 ± 0.2 mm/yr for the northern Blackwater fault, demonstrating higher localized displacement rates than previously recognized by coarse-resolution satellite imagery. Topographic diffusion modeling of cumulative scarp morphologies further reveals evidence of clustered mid-to-late Holocene rupture events characterized by single-event surface displacements ranging between 1.5 and 3.8 m. These findings reduce the long-standing discrepancy between geodetic and geologic slip rate estimates, highlighting the vital role of high-resolution topographic data in characterizing distributed intraplate deformation and refining probabilistic seismic hazard assessments across the western United States.
