Exciting news! We're transitioning to the Statewide California Earthquake Center. Our new website is under construction, but we'll continue using this website for SCEC business in the meantime. We're also archiving the Southern Center site to preserve its rich history. A new and improved platform is coming soon!

Revisiting historical earthquakes in our backyard: 1925 Santa Barbara and 1952 Kern County

Scott J. Condon

Published August 15, 2018, SCEC Contribution #8820, 2018 SCEC Annual Meeting Poster #080

We revisit the historic 1925 Santa Barbara and 1952 Kern County earthquakes using available seismic and geodetic data. As these two events occurred before the establishment of the World-Wide Standard Seismographic Network, our knowledge is very limited. For the 1925 Santa Barbara earthquake, we have digitized analog Bosch-Omori seismic records from the Berkeley Seismology Lab (BRK) using Teseo, a specialized digitization tool, and corrected for distortion caused by the instrument's mechanical arm. Our preliminary analysis, which treats this earthquake as a point source and the 2013 Mw 4.8 Isla Vista earthquake as an Empirical Greens Function (EGF), leads to a magnitude estimate of 6.4. For the 1952 Kern County Earthquake, our preliminary analysis reveals that the earthquake initiated on a thrust-dominant fault, dipping ~45°, and then migrated to a more energetic rupture with a different focal mechanism, after ~3 seconds. In view of the fact that the available bandlimited strong motion seismic data alone fails to constrain the source process, we are collecting geodetic observations to conduct a joint inversion with the goal of developing a slip model consistent with previous studies.

Citation
Condon, S. J. (2018, 08). Revisiting historical earthquakes in our backyard: 1925 Santa Barbara and 1952 Kern County. Poster Presentation at 2018 SCEC Annual Meeting.


Related Projects & Working Groups
Seismology