A Short-term Earthquake Forecasting Method by Geophysical Signals and Its Application in the China Seismic Experimental Site (CSES)

Yongxian Zhang, Zhiwei Ji, Changhui Ju, & Shengfeng Zhang

Submitted September 7, 2025, SCEC Contribution #14273, 2025 SCEC Annual Meeting Poster #TBD

We collected real-time geophysical observation data in and around the China Seismic Experimental Site (CSES) in southwest China operated by local earthquake agencies, including 1581 sensors at 193 stations. Among the 1581 sensors, 427 are for crustal deformation observation, 311 are for geomagnetism and geoelectricity, 467 are for ground fluid, and 376 are for supplementary observation including meteorologic observation.
We deal with the daily mean values from each sensor as a time series, calculate the difference between two time points, and determine it as ‘anomalous change’ when the difference exceeds the threshold defined by the value of N times of the mean square deviation (N could be any value above 1.0). We count the number of “anomalous change” out of all sensors and stations of each day and generate curves reflecting the variation of geophysical observations anomalies in the whole region with time. The results show that obvious increasement of the number of anomalies in geophysical observations occurs within about 1 month before most strong earthquakes in southwest China during 2020-2024, which implies that collaborative geophysical change exists in large scale in short-imminent term of seismogenic process.

Key Words
Short-term Earthquake Forecasting method, Geophysical Signal, China Seismic Experimental Site

Citation
Zhang, Y., Ji, Z., Ju, C., & Zhang, S. (2025, 09). A Short-term Earthquake Forecasting Method by Geophysical Signals and Its Application in the China Seismic Experimental Site (CSES). Poster Presentation at 2025 SCEC Annual Meeting.

Related Projects & Working Groups
Earthquake Forecasting and Predictability (EFP)