[S-CG49] Integrative seismic and secondary hazard/risk assessment

[SCG49-09] Rapid Simulation of Acceleration Waveform at Everest Seismic Station of the 2025 Ms6.8 Xizang Tingri Earthquake and New Progress of Green’s Function Database

*Zongchao LI¹, Zhiwei Ji², Jize Sun³, Hiroe Miyake⁴, Mengtan Gao¹, Junju Xie¹ (1.Institute of Geophysics, China Earthquake Administration, 2.Institute of Earthquake Forecasting, China Earthquake Administration, 3.Shenzhen Academy of Disaster Prevention and Reduction, 4.Earthquake Research Institute, The University of Tokyo)

Keywords:Everest Seismic Station, Xizang Tingri Earthquake, Green’s Function Database, Rapid Simulation

On January 7, 2025, a magnitude Ms6.8 earthquake occurred in Dingri County, Shigatse City, Xizang, China, causing severe damage near the epicenter. The affected area is located on a plateau at over 4,000 meters above sea level, where seismic stations are sparsely distributed. There is a lack of comprehensive reference data or basic seismic records within a 100 km radius, which are essential for quickly assessing the extent of earthquake damage and guiding post-earthquake reconstruction efforts. The high mountain region affected by this earthquake is mostly covered with permanent glaciers, such as those on Mount Everest, and contains numerous potential landslide sites. Studying the impact of earthquakes on the stability of glaciers and landslides is an important scientific concern. Given this context, this article focuses on an Ms3.9 small earthquake recorded at the XZ-ZHF seismic station, located 55 km from the epicenter. Using the empirical Green’s function method, the study considers parameter uncertainty to synthesize the acceleration waveform of the earthquake at this station. The research results indicate that the horizontal peak ground acceleration (PGA) at Zhufeng seismic station ranged from 70 to 190 cm/s², while the vertical PGA ranged from 40 to 140 cm/s². This corresponds to an instrument seismic intensity of VI-VII. These findings reflect the seismic intensity at the Zhufeng Seismic Station. When compared with the seismic response spectra of various probability levels in the fifth-generation Seismic ground motion parameters zonation map of China, and taking into account the structural integrity of local buildings, it is analyzed that the seismic intensity could cause more severe damage to general civil structures near the Zhufeng seismic station. Furthermore, it is expected that the earthquake damage near the epicenter is likely to be even more severe. Additionally, the earthquake may have implications for the stability of high-altitude glaciers and potential landslide bodies, and it is recommended that special attention be paid to these issues.
This study employs small earthquake data derived from our preliminary Green's function database, which is based on actual small earthquake waveforms and has been further optimized. The database currently integrates approximately 8 million small seismic waveforms nationwide for earthquakes with magnitudes ranging from Ms 2.0 to 5.0. The primary source of the earthquake data is China's fixed seismic network. More encouragingly, China's earthquake early warning network has been fully established, and in the future, the Green's function database will incorporate small earthquake data from China's earthquake early warning network. We are filled with anticipation for the potential of the Green's function database to advance earthquake research and disaster management, and we hope it can play an even greater role in earthquake prevention and disaster reduction efforts moving forward.