Report: Brett, CP. 1980. Cruise Report on Project 80/11. A Gravity and Magnetic Survey in the Northern North Sea. (IGS Report No 106) Navigation: Magnavox satellite navigation system integrated with MX610/MX600 doppler sonar and Arma Brown Mk I Mod 5 gyro compass. Decca Mk 21 Main Chain - optional integration with above. Equipment: Atlas Deso 10 echo sounder with hull mounted transducers (33 and 210KHz) and Edig 10 digitiser unit. LaCoste & Romberg S75 air-sea gravity meter. World Wide land gravity meter for base ties. Barringer proton magnetometer. The objective was to resurvey the Peterhead and Forties sheets of the IGS 1:250000 map series. The area had been surveyed previously in 1972 (MGU Project 73/04, IGS Report No 34). During the 1972 cruise there were considerable technical problems with the gravity meter and much of the data were of only moderate quality. Since 1972, subsequent surveys in adjacent areas further emphasised the inadequacies of the data and it became apparent that the area needed to be completely resurveyed.
