This sampling survey has been carried out by the Hydrographic Department of the Ministry of Defence, the survey took place from September to October 1970 in the Sea of the Hebrides on board HMS Hecla. They provided sample material to the Institiute of Geological Sciences (now BGS) who provided a geological determination. These data are archived by BGS. No BGS survey report currently available.

This geophysical survey has been carried out by, Institute of Geological Sciences (IGS) now British Geological Survey (BGS) for Department of Energy, the survey took place from May to September 1974 in the western English Channel on board the HMS Hecate. The purpose was to collect data to link deep seismic information to the outcrop geology. Sea floor data were collected using Echo Sounder, Gravimeter, Magnetometer, Sidescan Sonar. Sub-bottom profiling data were collected using Sparker. These data are archived by BGS. Details of the survey are contained in IGS Annual Report 1974.

We present a new gridded bathymetric compilation around Tristan da Cunha here defined by the following bounding box: 5 to 16.8W, 33 to 43.5S. This bathymetry grid was compiled from a variety of multibeam swath bathymetry data acquired during 7 different cruises (see lineage). The data is available as a grid of 0.001 degrees resolution in three different formats: NetCDF, ArcView ASCII and GeoTIFF formats using geographic coordinates on the WGS84 datum. This grid is an output of the UK FCDO 'Blue Belt' program and the following Natural Environment Research Council (NERC) BAS-ODA fundings: NE/R000107/1 and NE/T012439/1.