Abstract：To quantitatively estimate the various components contained in the observation sequence, deepen understanding of the physical meaning of observation, evaluate the observation environment, observation quality and monitoring capability of topographic change and seismic topographic change of the station, deepen the understanding of the observation data, and accurately identify the pre-earthquake anomalies, this paper takes the thermal body strain in Wenquan station as an example, selects the observation data of the three elements of thermal body strain in Wenquan station, auxiliary observations and meteorology, and uses the methods of Pertesv’s filtering, wavelet analysis and correlation analysis, etc. The influencing factors and characteristics of the periodic changes of the thermal body strain observation in Wenquan station are analyzed. The results show that: 1) The influencing factors of the annual periodic changes of the thermal body strain in Wenquan station may be at the borehole water level, and the thermal spring body strain phase lags the water level by about 31 days. 2) Air pressure is the main influence factor of thermal body strain monthly wave in Wenquan station. 3) Solid tide is the main influence factor of daily wave and semi-daily wave on thermal body strain in Wenquan station. 4) Body strain in Wenquan station has strong linear correlation with water level, air pressure and solid tide.
