This marine geophysical and sampling survey comprised three legs and formed part of the British Geological Survey (BGS) regional mapping project. It was undertaken from February to April 1973 in the Firth of Clyde and Malin Sea area using the MV Whitethorn. The main purpose was to obtain boreholes to prove the extent of the geology, standby work included 1) Sediment sampling in the Malin Sea and Clyde 2) Shallow seismic profiling in sea lochs to determine sediment distribution. 3) sediment sampling, current meter and shallow geophysics in conjunction with University College London. During the second leg engineering geology staff were on board to undertake sampling on fresh cores. Sea-bed samples and cores were collected using Gravity corer, Vibrocorer, shipek grab and Wireline drilling. Geophysical lines run included Pinger, sparker and echosounder equipment. Position fixing during the cruise was Main Chain Decca for standard sampling and geophysical lines and Decca RM 729 Alpine Radar Ranger for boreholes. These data are archived by BGS. Technical details of the survey are contained in BGS Technical Report WB/MI/73/2.