I the development of a marine seismic recording system II a magnetic survey of the faeroe bank

Abstract

The first section of the thesis reviews the design of marine seismic refraction systems which have been evolved to enable surveys to be carried out using only one ship. This is followed by a discussion of the design of a specific self-recording sonobuoy which stores the seismic information on magnetic tape, together with the specifications and circuit details of the system built at Durham University. Each buoy incorporates a four track tape recorder which is programmed, using an internal crystal clock, to switch on and off at predetermined intervals. The clock times the seismic arrivals and is periodically synchronised with time on board the shooting ship by the radio transmissions to the buoy. The seismic signal is recorded at two gain levels and there is a facility for wow and flutter compensation. Finally, there is a description of a refraction survey on the Iceland-Faeroe Rise, which regretably culminated in the loss of the buoy units.