Dynamic characteristics of moving-coil geophone with large damping

Abstract

The advantage of geophone with large damping in receiving and compensating high frequency signals is studied theoretically and experimentally. It is found that, as the damping ratio increases, the frequency characteristic of geophone in domain frequency region approximates to the acceleration characteristic gradually, thus the receiving frequency bandwidth of land seismic acquisition is widened and the record of high frequency signals is enhanced. The adopted micro-electronic technology not only increases the geophone damping largely, but also reduces the output impedance of geophone. The in-situ record data by self-designed geophones with large damping demonstrates higher visual frequency and S/N ratio, and stronger spectrum energy. The proposed method is expected to apply to the moving-coil geophone for high resolution seismic exploration.