Intra-Frame Deformation Model: Integrating InSAR and GNSS

Lavoisiane Ferreira, Yehuda Bock, David T. Sandwell, Katherine A. Guns, Xiaohua Xu, & Ray Thicklin

Published September 8, 2024, SCEC Contribution #14024, 2024 SCEC Annual Meeting Poster #074

We are developing an Intra-Frame Deformation Model for the significantly deforming regions of the U.S. (West Coast, Alaska, Hawaii, Caribbean). The project is funded by the National Geodetic Survey’s Geospatial Modeling Program as a complement to the new National Spatial Reference System (NSRS). Our starting point is the Dynamic Datum (Klein et al., 2019), a kinematic three-dimensional frame that provides changes in position (displacements) with respect to a reference epoch. For the horizontal, we combine an interseismic model and transients derived from continuous GNSS-derived daily displacement time series. For the vertical, we only use the observations, which are limited by the distribution and density of the GNSS network (~20-40 km). To increase the spatial resolution to <1 km in the vertical direction, we are in the process of integrating InSAR imagery and GNSS. Specifically, we are upgrading the SCIP web application for the Western U.S. (http://sopac-adj.ucsd.edu/scip/) for the inclusion of InSAR displacements, SCIP provides the expected 3-D GNSS displacements between any two epochs with respect to several reference frames [e.g., NAD83(2011) and ITRF2020], and eventually to the NSRS. We incorporate the interseismic model of Zeng (2024) for the Western U.S for the secular velocities of the GNSS reference stations. The transients are reflected in the daily GNSS displacement time series, a combination of JPL and SOPAC solutions obtained through a NASA funded project (http://sopac-csrc.ucsd.edu/index.php/measures-2/) and supplemented by the InSAR vertical information. We discuss the progress we are making to integrate InSAR/GNSS to improve the vertical displacement field in regions suitable for InSAR analysis.

Citation
Ferreira, L., Bock, Y., Sandwell, D. T., Guns, K. A., Xu, X., & Thicklin, R. (2024, 09). Intra-Frame Deformation Model: Integrating InSAR and GNSS. Poster Presentation at 2024 SCEC Annual Meeting.

Related Projects & Working Groups
Tectonic Geodesy