SCEC Award Number 11075 View PDF
Proposal Category Collaborative Proposal (Data Gathering and Products)
Proposal Title Space geodetic investigations of postseismic deformation due to the 2010 El Mayor-Cucapah (Mexico) earthquake
Name Organization
Yuri Fialko University of California, San Diego David Sandwell University of California, San Diego Gareth Funning University of California, Riverside Michael Floyd University of California, Riverside
Other Participants
SCEC Priorities A5 SCEC Groups Geodesy
Report Due Date 02/29/2012 Date Report Submitted N/A
Project Abstract
The April 4, 2010, .2$ El Mayor-Cucapah earthquake on the US-Mexico border was the largest earthquake to strike Southern California in the last 18 years. Shortly after the earthquake teams from SIO and UCR, in collaboration with colleagues from CICESE (Mexico) went to the field to conduct campaign GPS measurements to obtain coseismic offsets and establish a baseline for postseismic surveys. Continuous GPS coverage is reasonably good North of the US-Mexico border, but very poor to the South, so campaign GPS measurements are crucial for constraining the coseismic model, as well as characterizing the postseismic deformation. An earthquake of this size is expected generate a robust postseismic deformation transient, as the continuous and preliminary campaign GPS data already indicate. We propose to continue our campaign GPS measurements to capture time-dependent deformation following the El Mayor-Cucapah earthquake. The proposed research will focus on the campaign GPS data collection. The proposed observations, along with other available geodetic data, will be subsequently used to study the time-dependent response of the Earth to coseismic stress changes, and test the existing hypotheses of postseismic relaxation. We will conduct at least 2 campaigns in 6-month intervals to ensure that we capture the spatiotemporal evolution of the postseismic velocity field (the survey frequency may be adjusted based on the observed deformation rates). Each survey will involve two teams from SIO (3 people each), one team from UCR (2 people), and collaborators from CICESE (at no cost to this proposal). Fialko and Sandwell will be leading the SIO field teams. The surveys will be conducted using the SIO and UCR instrument pools.
Intellectual Merit Data collected under the auspices of this proposal will improve our understanding of time-dependent deformation following large earthquakes, and provide insights into stress transfer and interactions in a complex fault system in Southern California.
Broader Impacts This project provided training and support for several graduate
students, who participated in all aspects of the field work,
instrument deployment, data processing, and preliminary data analysis.
It also enabled collaboration between researchers from the US and
Exemplary Figure Figure 2