WITHDRAWN Spatial Changes in Earthquake Generated Ground Motion Observations: An Examination of Data From Four Small Aperture Arrays in Southern California
Description:
WITHDRAWN Ground motions recorded at one location are often extrapolated to nearby regions within a given radius. Here, we explore alternatives to simple extrapolation methods, accounting instead for the proximity of a station to primary fault zones. We use data from four small aperture seismic network deployments in southern California. Three of these deployments span, or are near, the San Jacinto fault zone and are linear arrays (YN.JF*, N=9, aperture 0.4 km; YN.RA*, N=9, aperture 0.25 km; and YN.TR* N=4, aperture 3 km) and one is a 2D array at Pinyon Flats Observatory (PF.BPH*, N=13, aperture = 1.2 km). To build robust catalogs an automated method is used to remove data with clipped waveforms and temporally overprinted waveforms from events in quick succession. All data are filtered 0.5-25 Hz. Using these refined waveform catalogs, peak ground acceleration (PGA) and peak ground velocity (PGV) are derived individually for each of the 3-component waveforms (vertical, north-south, and east-west) using one-minute waveform snippets. Associated metadata are stored in a data structure for additional analysis. These ground motion results are compared with theoretical estimates from Abrahamson et al., 2014. Generally, we find the PY.BPH* array data produce ground motions most similar to the theoretical values. The YN.JF* and YN.TR* array data produce smaller-than-expected ground motions and the YN.RA* array data produce larger-than-expected ground motions. We attribute these overall differences to site conditions. Results from array YN.JF* indicates that ground motions within the fault zone can be elevated in comparison with ground motions ~0.2 km off fault.
Session: Understanding and Modeling the Uncertainties in Earthquake Ground Motions [Poster]
Type: Poster
Date: 4/20/2023
Presentation Time: 08:00 AM (local time)
Presenting Author: Frank L. Vernon
Student Presenter: No
Invited Presentation:
Authors
Frank Vernon Presenting Author flvernon@ucsd.edu University of California, San Diego |
Debi Kilb Corresponding Author dkilb@ucsd.edu University of California, San Diego |
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WITHDRAWN Spatial Changes in Earthquake Generated Ground Motion Observations: An Examination of Data From Four Small Aperture Arrays in Southern California
Category
Understanding and Modeling the Uncertainties in Earthquake Ground Motions