Multi-Track InSAR Resolves Distributed, Seasonal, and Ridgecrest-Related Deformation Across the Southern Walker Lane
Yu Jiang, Jingyi Chen, & Daniel T. TrugmanSubmitted August 30, 2026, SCEC Contribution #15247, 2026 SCEC Annual Meeting Poster #TBD
In the southern Walker Lane, dextral shear and extension are distributed across fault systems along the eastern Sierra Nevada, Owens Valley, Panamint Valley, and Death Valley that have historically produced large and damaging earthquakes. Resolving this deformation informs strain partitioning and earthquake hazard. We use ~450 Sentinel-1 SAR images to generate ~33,000 interferograms from one ascending and two descending frames, producing a five-year time series from Jan 2020 to Dec 2024. Mountainous terrain challenges InSAR because reduced radar coherence and atmospheric delays can mask millimeter-scale deformation. We mitigate these effects through multi-temporal phase reconstruction and adaptive atmospheric corrections. Independent benchmarks show closer agreement with GPS than NASA/JPL/OPERA displacement products and conventional MintPy/StaMPS-SBAS processing (Jiang et al., in review). The InSAR solution is developed independently of GPS, but we use >30 GPS stations for validation after their velocities are projected into the satellite line-of-sight direction. Overlapping ascending and descending observations are combined to estimate east and vertical motion assuming a negligible north-south contribution, and the resulting time series are decomposed into linear, annual, and seasonal signals.
Preliminary results show a broad west-to-east increase in east-component velocity: median profile velocities rise from ~-3 to 1 mm/year, a regional difference of 4 mm/year. This complements GPS-derived strain rates concentrated in northern Owens Valley and broadening southward across Panamint Valley and southern Death Valley (Hammond et al., 2024). The vertical field has no comparable regional gradient; localized subsidence around the Coso geothermal field reaches ~15 mm/year. Across the 2019 Ridgecrest rupture zone, subsidence occurs mainly west of the ruptures and uplift to the east. Representative time series show persistent multi-year east-component displacement near Ridgecrest and annual and seasonal modulation of Coso subsidence. After removing the long-term linear trend at each pixel, the remaining deformation shows spatially coherent seasonal patterns across the region. Multi-track InSAR thus resolves regional gradients, coherent seasonal deformation, and distinct Ridgecrest and Coso signals, providing a geodetic framework for evaluating strain partitioning and spatiotemporal links to regional seismicity.
Key Words
InSAR, Walker Lane
Citation
Jiang, Y., Chen, J., & Trugman, D. T. (2026, 08). Multi-Track InSAR Resolves Distributed, Seasonal, and Ridgecrest-Related Deformation Across the Southern Walker Lane. Poster Presentation at 2026 SCEC Annual Meeting.
Related Projects & Working Groups
Tectonic Geodesy
