British Geological Survey (BGS) Geophysical Survey 1971/3: Bristol Channel and northern Celtic Sea (14/05/1971 to 07/06/1971)

Report: Tully, MC. 1971. Bristol Channel Cruise Report for MV Researcher. MGU Project 71/03. (IGS Report No 20) Positioning: Decca Mk12 receiver Echo sounding: ORE sub-bottom profiler was used as an echo sounder Sonar systems: Transit sonar (Kelvin Hughes?). Seismic systems: Sparker system: EG&G sparker system with 263b hydrophone streamer and 254 recorder. Most lines run at 1kJ. Also various multi-electrode sparker units were tested Gravity meter: LaCoste and Romberg gravity meter. Magnetometer: Barringer magnetometer