This is the collection of cores and samples held by BGS for the sea areas around the UK. It includes material collected by BGS during its mapping projects and material donated to BGS by other organisations. The main core and sample types are grab samples (sea-bed), gravity cores, vibrocores and rock-drill cores (up to 6m in length), and borehole cores (up to 274m in length). The sea-bed grab samples are Holocene sediments present at the sea-bed and are stored in plastic jars. Where possible, sub-sample material has been retained after analysis. The bulk of the cores consist of Holocene and Pleistocene material. The rest are of bedrock ranging in age from Neogene to Pre-Cambrian. A lot of the core was collected in plastic liner tubing and the unlithified cores have been split vertically. The bulk of the material was collected in the late 1960s, 1970s and 1980s and early 1990's with ongoing additions of new sample and cores each year. The distribution is very variable, but, in general, there are grab samples and/or shallow cores spaced about every 5 - 10km across the entire UK Continental Shelf. In some localised areas the sampling density is much higher. The samples and cores are applicable to a wide range of uses including environmental, geotechnical and geological studies.