British Geological Survey (BGS) Geophysics Survey 1971/4: Brest to Scilly Isles (gravity/magnetics), northern Irish Sea (refraction), Malin Sea (gravity) and off Skye (refraction) (08/06/1971

Report: Bacon, M. 1971. Irish Sea Refraction Experiments. MGU Project 71/04. (IGS Report No 19) Positioning: Presumed to be Decca Mainchain Echo sounding: No information but may have been ORE sub-bottom profiler as on previous cruise 71/03. Seismic systems: Refraction ICI Aquaseis was the explosive source with UEL sonobuoys. No digital navigation data for this. Gravitymeter: LaCoste and Romberg gravity meter. Magnetometer: Barringer magnetometer