Mapping LA basin depth with converted seismic phases

Yan Yang, & Robert W. Clayton

Published August 11, 2021, SCEC Contribution #11272, 2021 SCEC Annual Meeting Poster #192

Sedimentary basins trap and amplify earthquake ground motion energy. One of the most important basin structure parameters is the depth-to-basement. The mapped depth-to-basement of the densely populated Los Angeles Basin is usually largely smoothed due to the sparse seismic and gravity measurements. The Community Seismic Network-Los Angeles Unified School District (CSN-LAUSD), a network of 400 low-cost accelerometers located in schools in the LA basin, provides a good opportunity for studying the detailed basin structure because of their location. We use the differential travel times between direct S and converted SP phases recorded by CSN-LAUSD network during a few deep earthquakes beneath the array to map the LA basin depth. The results from different events are consistent. The resulted pattern of deeper basin the east LA is similar with measurements from seismic tomography and gravity surveys, but this independent constraint has denser data coverage and thus higher resolution.

Citation
Yang, Y., & Clayton, R. W. (2021, 08). Mapping LA basin depth with converted seismic phases. Poster Presentation at 2021 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology