SCEC Award Number 18201 View PDF
Proposal Category Individual Proposal (Data Gathering and Products)
Proposal Title 2018 SCEC/SURE internship project proposal: Updating GPS site positions and velocities and improving GPS coverage in southern California for the Community Geodetic Model
Investigator(s)
Name Organization
Gareth Funning University of California, Riverside
Other Participants Rachel Terry (Graduate student, UCR)
SCEC Priorities 1a, 2a, 3e SCEC Groups Geodesy, SDOT, CXM
Report Due Date 03/15/2020 Date Report Submitted 03/16/2020
Project Abstract
 We surveyed over 40 campaign GPS sites in the Inland Empire and Mojave Desert areas of southern California in the summer of 2018 and winter of 2019. These surveys will be incorporated into the SCEC Community Geodetic Model, and served as vital reconnaissance for the response to the July 2019 Ridgecrest earthquakes, which occurred in the northernmost part of our study area.
Intellectual Merit We collected GPS data in two areas of high current seismic hazard – the Inland Empire (home of the northern San Jacinto fault and the Cajon and San Gorgonio Pass segments of the San Andreas fault), and the Mojave desert (containing the Eastern California Shear Zone and Garlock fault). The data collected will be used to estimate updated campaign GPS velocities for future updates of the SCEC Community Geodetic Model. They were also used to provide a strong constraint on site positions before the 2019 Ridgecrest earthquakes, and facilitated a rapid response to those events (and measurements of coseismic offsets for each).
Broader Impacts The field work elements of the project were led by members of two underrepresented minorities – a Latino undergraduate intern and a female graduate student. The data collected will be used to update secular deformation rates across the region, which are inputs for seismic hazard models that are widely used by local governments and agencies for hazard remediation planning.
Exemplary Figure Figure 2: GPS sites measured during this project. Gold, filled triangles: data collected by intern Eneas Torres-Andrade, targeting the San Andreas and San Jacinto faults, in the summer of 2018. Red hollow triangles: data collected by graduate student Rachel Terry, targeting the Mojave San Andreas, Garlock and Blackwater faults, in the winter of 2019. The latter stations include multiple sites in the vicinity of the city of Ridgecrest, which were reoccupied in the aftermath of the nearby earthquakes in July 2019.