Report: Armstrong,EJ. 1979. Cruise Report on Project 79/12. A Regional Survey in the South West Approaches, MV Sperus. (IGS Report No 99). The two legs of this survey were designed to infill the regional coverage obtained in 1978 and to run a number of lines on the Haig Fras sheet of IGS 1:250000 map series, using shallow seismic profiling, gravity and magnetic mwthods. In addition, a detailed survey of part of the area was to be run using the Huntec Deep Tow Boomer system.