Field Experiments on the Electroseismic Effect

Electrical signals generated in the earth as a result of seismic energy were investigated as a possible means for detecting low-frequency seismic events. It was found that the conversion of seismic to electrical signals was highly variable with different detection locations. For detection of small seismic events, the method could not be recommended over the use of conventional inertial seismometers because of its low conversion efficiency. For strong motion measurements, however, the method should be given consideration if a suitable geological environment is found and a calibration means is used. Signals of the "E" type, i.e., those produced by electrofiltration potentials, were found to be predominant in these experiments.