Laboratory Borehole Model

Abstract

An experimental method for acquisition offull waveform acoustic logging (FWAL) data from scaled laboratory borehole/formation models is under development. A spark-gap source, fabricated in the lab, is used in conjunction with a piezoelectric receiver. It is found that the source/receiver signature covers a suitable frequency range for the 32:1 scaling required by the 6.4 mm model borehole diameter. Waveforms collected from water-filled boreholes in aluminum and Lucite, simulating fast and slow formations, clearly exhibit the characteristic arrivals of those formations.