Progress in Studying of 3D Crustal Deformation and Seismic Risk Assessment of the Tibetan Plateau Using Geodetic Observations

The Tibetan Plateau is an ideal and unique natural experimental field for geoscience research. Scientific issues related to crustal deformation, material escape pattern, and seismic activity of the Tibetan Plateau attract long-term attention from the geologists. Spatial geodetic techniques represented by global navigation satellite system (GNSS) and interferometric synthetic aperture radar (InSAR), with their high spatiotemporal resolution, widely coverage, and high observation accuracy, have been applied to current crustal deformation measurements and play an essential role in seismological research. First, we review the research progress on three-dimensional crustal deformation in the Tibetan Plateau, including researches related to horizontal crustal deformation using GNSS, vertical crustal deformation study using a combination of GNSS and leveling, regional deformation measurements using InSAR, and the construction of a three-dimensional deformation field using multiple geodetic data. Second, in conjunction with three-dimensional crustal deformation, we review the research progress on seismic risk assessment of active faults in the Tibetan Plateau, and discuss the probabilistic seismic risk assessment that considers earthquake stress perturbations. The role of geodetic measurements in seismic risk assessment is also discussed. In the future, more attention should be paid to the following three aspects. First, dense GNSS network should be established in observation gaps to refine the crustal motion and deformation pattern of the Tibetan Plateau. Second, geodetic observations during “quasi-complete seismic cycle” should be conducted to analyze the deformation characteristics and evolution process of fault zones.Third, seismic risk assessment based on machine learning should be developed using multisource data from seismology, geology, and geodetic observations.