InSAR/GPS time series deformation of the 2018 Kilauea event: Preparation for a large Southern California event

Bridget R. Smith-Konter, Xiaohua Xu, Lauren Ward, Liliane Burkhard, & David T. Sandwell

Published August 15, 2018, SCEC Contribution #8746, 2018 SCEC Annual Meeting Poster #138

In preparation for the next major earthquake in Southern California, a key task of SCEC5 is to develop methods to integrate dense spatiotemporal geodetic datasets for post-earthquake rapid response. Events like the 2018 Kīauea Volcano eruption, observed every three days since May 2nd by ESA’s Sentinel-1 satellites, provide an unprecedented opportunity to refine our GPS/InSAR time series integration capabilities in preparation for future Southern California events. Using open source software GMTSAR, we processed all ascending and descending Sentinel-1A/B InSAR line-of-sight (LOS) data for the Big Island of Hawai'i since the start of the eruption, and have been actively providing these data to the scientific community as they become available (http://pgf.soest.hawaii.edu/Kilauea_insar/). Here we present a crustal deformation time-series for the 2018 Kilauea event (April 30 - August 9) using integrated GPS/InSAR measurements. We geometrically align all Sentinel-1 acquisitions using precise orbital information and select interferograms based on a 150-m perpendicular baseline and 60-day temporal baseline. Interferograms are masked with a universal stacked coherence, nearest-neighbor interpolator and then unwrapped with SNAPHU. Lastly, the time-series is constructed using a common-scene stacking technique to absorb turbulent atmospheric noise and coherence-based SBAS to recover ground deformation. These data provide critical modeling constraints of the ~90-day deformation event at Kīlauea from several sources: (1) the April 30th collapse of Pu'u 'Ō'ō crater, (2) the May 1st dike intrusion, propagation, and subsequent contraction of the lower East Rift Zone, (3) sprawling deformation from the May 4th Mw6.9 Leilani Estates thrust earthquake along the south flank region (subsidence and southeast-directed displacement in excess of 0.3 m and 0.8 m, respectively), and (4) continuous deflation of Kīlauea’s summit region as large volumes of magma are withdrawn. Moreover, the continual near-real-time geodetic observations spanning the last three months of the 2018 Kīlauea eruption provide a exceptional testbed for rapid hazard response and a unique opportunity to further refine our time series integration methods in preparation for post-earthquake rapid response in Southern California.

Citation
Smith-Konter, B. R., Xu, X., Ward, L., Burkhard, L., & Sandwell, D. T. (2018, 08). InSAR/GPS time series deformation of the 2018 Kilauea event: Preparation for a large Southern California event. Poster Presentation at 2018 SCEC Annual Meeting.

Related Projects & Working Groups
Tectonic Geodesy