Sediment samples were collected from selected areas of the southern North Sea as part of the ongoing Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment (SEA2). The aim of the survey was to describe the physical, chemical and biological characteristics of a range of offshore sandbanks and pockmarks (more than 12 km from the coast). The survey focused on three main study areas in the southern North Sea: the Dogger Bank study area; the South Fladen Pockmark study area and a major sand bank area off the coasts of Norfolk and Lincolnshire. This report presents the following sediment data: Total hydrocarbon and n-alkane concentrations; 2 to 6 ring polynuclear aromatic hydrocarbons (PAH) content; selected metals concentrations.