SCEC Award Number 16301 View PDF
Proposal Category Individual Proposal (Integration and Theory)
Proposal Title Vertical component of secular surface velocities from a joint analysis of InSAR and GPS data
Investigator(s)
Name Organization
Yuri Fialko University of California, San Diego
Other Participants Katia Tymofyeyeva - grad student
SCEC Priorities 1d SCEC Groups Geodesy
Report Due Date 03/15/2017 Date Report Submitted 05/19/2017
Project Abstract
 Many tectonic and anthropogenic processes are expressed in uplift or
subsidence of the Earth's surface. Examples are: interseismic
deformation due to active dip-slip faults, postseismic relaxation,
hydrologic loading, geothermal and hydrocarbon production, etc. A
robust and accurate characterization of vertical deformation of the
Earth's surface is an important component of the Community Geodetic
Model (CGM), yet so far it has proven difficult as continuous GPS data
are less sensitive to the vertical component of deformation compared
to the horizontal component. The Interferometric Synthetic Aperture
Radar (InSAR) data are, on the other hand, highly sensitive to
vertical motion. We have developed a method for combining InSAR and
continuous GPS data to produce a high-resolution map of vertical
velocity. The method was applied to study an area of active
deformation at the southern end of the San Jacinto fault zone using
Envisat InSAR and GPS data. The data analysis can be readily extended
to include all of Southern California.
Intellectual Merit This project addressed the following research priority of the 2016 SCEC
Science Collaboration Plan in the disciplinary activity of Tectonic Geodesy:

- Contribute to the development of a
Community Geodetic Model (CGM). Develop a crustal motion model
consisting of velocities and time series for southern California that
leverages the complementary nature of GPS and InSAR observations. This
requires development of optimal methods for combining GPS and InSAR
data.

- Analysis of geodetic data to address
specific SCEC4 research targets. Studies addressing geodetic/geologic
slip rate discrepancies, assessing the role of lower crust/upper
mantle processes in driving fault loading, and developing more
physically realistic deformation models.
Broader Impacts The proposed collection and analysis of space geodetic data will
improve our understanding of the associated seismic hazard to
populated areas in Southern California. This project has provided
training and support for three graduate students. This project
provided training and support for a female graduate student
(Tymofyeyeva). The PI (Fialko) used results of this study in a
graduate-level seminar taught at SIO.
Exemplary Figure Figure 2e