SCEC Award Number 15200 View PDF
Proposal Category Individual Proposal (Data Gathering and Products)
Proposal Title Collaborative Research: Documenting the coseismic surface deformation field for the 1952 Ms 7.7 Kern County earthquake: Using COSI-Corr 3D pre- and post-event DEM differencing to analyze a 62-year-old analog for future Los Angeles-area blind thrust earthquakes
Investigator(s)
Name Organization
James Dolan University of Southern California
Other Participants Participating Graduate Student:
Alex E. Hatem (University of Southern California)

Collaborators:
John H. Shaw (Harvard University)
Sebastien Leprince (California Institute of Technology)
Francois Ayoub (California Institute of Technology)
James Hollingsworth (ARUP Consulting, London, UK)
SCEC Priorities 4a, 4b SCEC Groups Geology, SDOT, WGCEP
Report Due Date 03/15/2016 Date Report Submitted 04/28/2016
Project Abstract
 We have begun troubleshooting the image correlation workflow for the 1952 Mw ~ 7.3 Kern County earthquake. This event has proven to be an extremely challenging one to study via air photos for multiple reasons: (1) lack of camera calibration report; (2) lack of accurate georeferenced points; and (3) poor image scans on first retrieval from library. We have identified and mitigated these issues by redesigning the originally proposed workflow. Air photos will now be mosaiced using Structure from Motion, which will independently derive the camera calibration information not recorded during the aerial image capture. From there, we will pursue two independent workflows, one using COSI-Corr and one using Iterative Closest Point (ICP) matching to: (1) minimize error in the correlations; and (2) test the viability of using ICP on legacy air photo differencing. Our results will yield the oldest (yet) legacy air photo correlation, and the resulting near-field coseismic deformation maps from a sizeable blind thrust earthquake will provide a powerful analog for deformation in future Puente Hills or Compton blind thrust ruptures beneath metropolitan Los Angeles.
Intellectual Merit Work on the Kern County earthquake will enhance our understanding of the coseismic deformation field of blind and oblique-slip ruptures. We aid in the detailed geologic investigation of a complex, poorly understood fault (priority 4a) in the White Wolf fault. Understanding the White Wolf fault will aid our attempts to assess the hazard posed by the Puente Hills fault by giving a direct analog of a blind thrust rupture beneath the southern California.
Broader Impacts In addition to the obvious implications of this work for understanding deformation patterns in folding and blind thrust earthquakes beneath Los Angeles, this project has provided a female doctoral student (Alex Hatem) with state-of-the-art training in cutting edge image correlation techniques that she will continue to pursue throughout her academic career. This effort has also involved other graduate students within the Active Tectonics research group at USC, using the expertise of other doctoral student (Chris Milliner and Rob Zinke) during workflow troubleshooting. The results of this study will be presented at a future SCEC meeting and will be published in a peer-reviewed journal.
Exemplary Figure Figure 1: LEFT: Pre-event image; RIGHT: Post-event image. The green arrow in both images points to a dirt road. Pink arrows points to a section of sinistral surface rupture observed only in the post-event image. Such comparisons confirm that surface rupture is evident when qualitatively correlating the image pair.