PALEOSEISMIC INVESTIGATION OF THE ROSE CANYON FAULT ZONE, SAN DIEGO, CA
The Spanish Bight fault segment, which runs through the San Diego International Airport and splays into San Diego Bay, is a critical part of the RCFZ. San Diego Bay is a pull-apart basin created by a step in the RCFZ where subsidence and Holocene sedimentation record the paleoseismic history of the fault zone. Additionally, the Spanish Bight fault potentially records changes in fault character and slip history as the RCFZ approaches this transtensional step-over. We interpreted high-resolution Chirp sub-bottom data that was collected from within San Diego Bay, offshore of the San Diego International Airport. We also extracted data from existing geotechnical reports, including cone penetrometer tests, core logs, and radiocarbon dates collected within the airport. Together, these data were used to generate a detailed active fault map and to resolve a stratigraphic framework between the airport and bay sediments. We compared these data with the paleoseismic records from other onshore fault segments to identify rupture patterns and evidence for past earthquake clustering or triggering.