Edgar A. Bowden

On-bottom seismometer electronic system

An ocean bottom seismometer unit records refraction waves from a seismic source. The refraction waves are digitzed and stored in a magnetic memory. Periodically, a tape recorder is started and digital samples are transferred from digital memory to tape during a time in which operation of the tape recorder will not generate spurious noise signals which interferes with the detection of the refraction waves. The water break is detected and the time of its occurrence is digitized. Only the digitized time of the water break occurrence is recorded thereby permitting shortened record length and increased record storage capacity.

Gun shot control unit for seismic exploration

A gun shot control unit for a seismic exploration system compensates for the inherent delay between the shot command signal and the actual occurrence of the seismic pulse. A digital clock is synchronized with an external source. Timing pulses occurring at a time preceding the timing pulse upon which the occurrence of a seismic pulse is desired are produced by the clock. These timing pulses start a digital counter at a time preceding the desired time of occurrence of the seismic pulse. This counter is adjustable so that the delay which interposes between the timing and the actual occurrence of the seismic pulse can be minimized.