Tectonic geomorphology and segmentation along the Calaveras fault zone from QUAKES-I and 3DEP topography

Madeline F. Schwarz, Malinda G. Zuckerman, Celina Driver, Ramon Arrowsmith, Ryan Applegate, Robert Zinke, Andrea Donnellan, & Curtis Padgett

Submitted September 7, 2025, SCEC Contribution #14927, 2025 SCEC Annual Meeting Poster #TBD

The Calaveras fault zone is characterized by distributed faulting which displays aseismic creep and hosts moderate to large earthquakes that threaten the San Francisco Bay Area. USGS 3DEP lidar collected in 2018 provides 1m bare earth topography of the Calaveras fault zone. NASA/JPL QUAKES-I stereoimagery collected from October 2022 science flights produced 1.5-meter digital elevation models (DEMs), 84 cm/pix ortho-mosaics, and true-color point clouds from which fault zone geomorphology can be mapped in detail. We conducted fault mapping and spectral analysis of the Calaveras fault zone using 2022 QUAKES-I stereoimaging and 2018 3DEP lidar data. Mapping was conducted using a systematic geomorphology-based approach from QUAKES-I orthorectified imagery and topographic derivative layers computed from 3DEP lidar and QUAKES-I elevation data. Spectral filtering of topography using the discrete Fourier transform (DFT) of the elevation data was used to evaluate the amplitude, wavelength, orientation, and periodicity of geomorphic indicators of faulting such as fault scarps, pressure ridges, landslides, and channels. We filtered the elevation DFT by wavelength ranges to identify fault indicators along the Calaveras. We characterize the fault zone geometry including fault discontinuities and primary and secondary fault structures. With this data we intend to better understand fault segmentation along the Calaveras and how faulting and surface processes interact to shape topography.

Key Words
Calaveras, Fault Mapping

Citation
Schwarz, M. F., Zuckerman, M. G., Driver, C., Arrowsmith, R., Applegate, R., Zinke, R., Donnellan, A., & Padgett, C. (2025, 09). Tectonic geomorphology and segmentation along the Calaveras fault zone from QUAKES-I and 3DEP topography. Poster Presentation at 2025 SCEC Annual Meeting.

Related Projects & Working Groups
Earthquake Geology