Fusion analysis of co-seismic response between broadband tiltmeters and broadband seismometers in Chengde area

This article focuses on the co-seismic waveforms collected by the VP type broadband tiltmeters and the BBVS-120 type broadband seismometer at the Chengde seismic station. Using the methods of wavelet analysis and short time Fourier transform, six seismic waveforms were analyzed, including time frequency characteristics and frequency band response. Energy is concentrated in 0～0.5 Hz. They have high consistency in waveform, frequency response, and power spectral density. Using empirical formulas to fit the relationship between the maximum amplitude and magnitude, the maximum amplitude formulas for the near and far earthquakes of the broadband tiltmeter is obtained. There is a good correspondence between the maximum amplitude of the broadband tiltmeters and the broadband seismometer in the Chengde area. Using the seismic wave body wave magnitude calculation formula, three seismic waves were selected to calculate the body wave magnitude for the earthquakes recorded by the broadband tiltmeters and broadband seismometer. The results showed that when the seismic wave frequency was less than 0.5 Hz, the corresponding relationship between the body wave magnitudes calculated by the two has a good correspondence.