The measurement and analysis of similarity degree on data from two types of seismic recorders

Abstract

Seismic instruments are widely used in projects related to geophysical prospecting. Quality data from seismic recorders help to determine subterranean structures with high precision. This paper first introduces a field experiment carried out by deploying seismic stations equipped with two kinds of seismic recorders: GEI (China) and Reftek 130 (USA). Then, the three-component seismograms from GEI are measured and evaluated by comparing with those from Reftek 130 in different aspects: waveforms in time and frequency domain, quantitative analysis by calculation and statistic of correlation coefficient, and signal to noise ratio of seismic signal. Our results were presented by multiple images as the following: (I) Both the time and frequency waveforms of GEI were almost exactly coincident with those of Reftek 130, with over 98.60 percent of the correlation coefficients in the time domain within 0.95–1.0, and all those in the frequency domain above 0.9977. (II) The accurate time lag estimation of GEI’s signal was gained by the lag and correlation algorithms based on left–right sliding windows. The GEI clock was 7.3545 ns behind the Reftek 130 clock after every 1 s, which could be utilized to correct the internal clock to improve the synchronous accuracy of seismic recorders. (III) Some seismic signals from GEI were obviously stronger than those from Reftek 130. Our results may potentially promote and support the optimization of seismic recorders and their application in geophysics methods.