Sentinel-1 Time Series of Transient Creep on the Concord Fault, Eastern Bay Area
Date: 4/25/2019
Time: 11:30 AM
Room: Puget Sound
Advances in SAR data acquisition allow the modern satellite missions to provide surface displacement observations at high spatial resolution and frequent repeat times in areas where measurements from other geodetic instruments may be sparse or unavailable. The PSInSAR technique is often used for estimating displacement time series with high precision, by confining the analysis to the most stable pixels. However, it is limited by its restriction to coherent targets and the assumptions required to identify them. The SqueeSAR technique, proposed by Feretti et al. (2011), mitigates some of these limitations by allowing for the combined processing of both permanent and distributed scatterers. We apply the SqueeSAR method to the study of shallow fault creep on the Concord Fault in the Eastern San Francisco Bay Area, where continuous GPS stations and other geodetic instruments are not available close to the fault to provide consistent spatiotemporal coverage. We use data from the European Sentinel-1 mission to observe a transient shallow creep event on the Concord fault. Observations from two overlapping satellite tracks with distinct look geometries (descending track 42 and ascending track 35) allow us to separate the surface displacements into fault-parallel and vertical components of motion, assuming that fault-perpendicular surface motions are negligible. We present cumulative displacements over the time period of available Sentinel-1 observations, from 2015-2018, as well as relative displacement time series for points on opposite sides of the fault. We are able to determine that the event began in the summer months of 2017, with variable slip along the fault, and a peak cumulative slip amplitude of approximately 15 mm in the direction parallel to the fault trace.
Presenting Author: Ekaterina Tymofyeyeva
Authors
Ekaterina Tymofyeyeva katia.tymofyeyeva@jpl.nasa.gov Jet Propulsion Laboratory, California Institute of Technology, San Diego, California, United States Presenting Author
Corresponding Author
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Heresh Fattahi Heresh.Fattahi@jpl.nasa.gov Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States |
David P S Bekaert david.bekaert@jpl.nasa.gov Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States |
Piyush Agram Piyush.Agram@jpl.nasa.gov Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States |
Sentinel-1 Time Series of Transient Creep on the Concord Fault, Eastern Bay Area
Category
Advances in Tectonic Geodesy