f Modern Geophones, Do They Meet the Demands of Shallow Seismic Measurements?

The paper describes investigations of parameters such as spurious resonance, natural frequency and coupling, which influence the high-frequency response of standard geophones. Coupling factors are determined along a survey live to demonstrate their variation from place to place. The time shifts found from this field investigation show that coupling has a significant effect on travel time determination. By choice of natural frequency, the influence of phase shift variations can be minimised in the frequency band of interest.