The British Geological Survey hold a collection of data recorded during marine geophysical surveys which includes digital data and analogue records. These data result from approximately 350,000 line kilometres of multi-instrument geophysical survey lines. The dataset includes seismic, sonar, magnetic, gravity, echo sounder, multibeam bathymetry and navigation data. The seismic data are mainly airgun, sparker, boomer and pinger data. Most of the data were collected by BGS, but the collection also includes some third party data. The data are primarily from the UKCS (United Kingdom Continental Shelf). The data are stored within the National Geoscience Data Centre (NGDC) as the Marine Environmental Data and Information Network (MEDIN) Data Archive Centre (DAC) for Geology and Geophysics. The majority of legacy geophysical paper records are available as scanned images. Other records can be scanned on request. Older records are of variable quality. Data not yet available online, including digital SEG-Y data, are available on request from enquiries@bgs.ac.uk. The data are applicable to a wide range of uses including environmental, geotechnical, geophysical and geological studies. For more information, refer to Fannin, N. G. T. (1989) Offshore Investigations 1966-87. British Geological Survey Technical Report WB/89/2, British Geological Survey.