SCEC Award Number 11170 View PDF
Proposal Category Collaborative Proposal (Data Gathering and Products)
Proposal Title Investigating strain localization and Moho offsets across major strike slip faults in southern California
Investigator(s)
Name Organization
Meghan Miller University of Southern California James Dolan University of Southern California
Other Participants
SCEC Priorities C, A3, A11 SCEC Groups Seismology, LAD
Report Due Date 02/29/2012 Date Report Submitted N/A
Project Abstract
 We have continued our work on imaging the deep crustal structure across strike-slip faults in Southern California using P receiver functions. We focused on the San Jacinto fault zone where there are a concentration of broadband seismometers across the fault, which has allowed us to address questions concerning the depth of plate boundary zone, discreteness of the shear zone, how deformation is occurring in the lower crust, which will allow for inference on the strength of the lithosphere. In order to make robust interpretations of the receiver function images we have produced a series of synthetic tests of possible velocity structures across a major strike-slip fault such as the San Jacinto fault. The work was presented in a poster presentation by Panxu Zhang at the SCEC annual meeting in 2011 and is the focus of her master’s thesis at USC.
Intellectual Merit We have produced P receiver functions of the crustal and lithospheric structure beneath the San Jacinto fault zone where there are a concentration of broadband seismometers. This has allowed us to address questions concerning the depth of plate boundary zone, discreteness of the shear zone, how deformation is occurring in the lower crust, which will allow for further inference on the strength of the lithosphere and how transform plate boundaries develop.
Broader Impacts Graduate student, Panxu Zhang, is writing up this work for her master’s thesis at USC and is concurrently writing a draft of a manuscript.
Exemplary Figure Figure 3: Common conversion points (CCP) stacking of P receiver functions along three profiles in San Jacinto Fault Zone. Fault traces are shown as grey lines on the map (SJF = San Jacinto, SAF = San Andreas Fault, EF = Elsinore Fault). Positions of cross sections are plotted as blue lines on map on the left. Red crosses represent the stations used in the CCP stack. Locations of Elsinore fault and San Jacinto fault and our interpretation of the Moho are marked on the profiles. Note that a Moho offset can be seen beneath the major faults.