Project Abstract
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The primary goal of this project is to provide explicit contemporary ground displacement products attributed to tectonic and both natural and anthropogenic non-tectonic sources in the SCEC region. Interseismic creep may localize along the fault or may distribute across a limited width about the fault while the surface deformation off the fault usually spreads out in a long-wavelength pattern. On the other hand, human activities such as groundwater pumping, hydrocarbon and geothermal activities may result in highly localized ground deformation. Temporally, hydrologically driven elastic/poroelastic displacements are believed to be generally correlated with the seasonal precipitation and water level changes. Here we rely on the existing CGM efforts of 2014-2018 Sentinel-1A/B InSAR results from Sandwell & Xu which incorporate GPS results generated by Zeng & Shen. We attempt to determine the presence of seasonal features and further quantify the peak-to-peak amplitude and phase using an efficient statistical strategy referring to the number of peaks and troughs in the first-order variations of time-series deformation. We obtained higher-level time-series products including the secular rates, seasonal amplitude and phase. The outstanding discontinuities and high-frequency signals in these maps reflect deformation due to various tectonic and non-tectonic features such as faults, the boundaries between basins and ranges, the hydrogeological heterogeneities contained in aquifer systems, and industrial production wells. This project helps better understand the coexisting tectonic and non-tectonic processes and their potential interaction across California, and also assists the earthquake hazard assessment and mitigation for the SCEC community, the public, and industry. |
