This report contains heavy metal concentrations (As, Ba, Cr, Cu, Cd, Fe, Hg, Pb, Mn, Ni, Sr, V and Zn) and sedimentological characteristics (particle-size analysis) which were determined in respectively 61 and 68 samples for the Atlantic margin Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment (SEA4) . A spreadsheet of data is available.

This report is a contribution to the Strategic Environmental Assessment (SEA6) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). This report describes the physical oceanography of the Irish Sea from St George's Channel in the south to the North Channel and the Clyde Sea in the north. The report covers the topography and depth of the sea floor, the tides, the impact of storms, stratification and its consequences and the mean circulation, all with a view to mean and extreme conditions. The predominant dynamical process is the semi-diurnal tides, with areas of both high and low energy embraced. Superimposed on this is the full range of water column structure areas that are well mixed throughout the year; areas that stratify thermally in summer; areas of freshwater influence from river discharges, leading both to nearshore density gradients and stratification; frontal regions between the well-mixed and stratified regions. The movement of the water and the amount of mixing prescribe physical effects, such as forces on structures and the movement and dispersion of contaminants, but also significantly influence biogeochemical processes including sediment erosion / deposition and movement, particularly of suspended sediment, benthic exchanges and primary productivity (via stratification, nutrient exchanges and light levels).

This report is a contribution to the Strategic Environmental Assessment (SEA4) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). Twelve marine mammal species occur regularly in the SEA4 area: grey seal, harbour seal, hooded seal, harbour porpoise, white-beaked dolphin, Atlantic white-sided dolphin, Risso's dolphin, long-finned pilot whale, killer whale, minke whale, fin whale and sperm whale. A further eleven cetacean species and four pinniped species are occasional visitors. This report describes the distribution and abundance of these mammals and their ecological importance. The SEA4 area is an important area for cetaceans, but little is known about the abundance or seasonal distribution of many species. Marine mammals make use of sound for a variety of purposes: finding prey, detecting predators, communication and probably navigation. The offshore oil and gas industry generates underwater noise at every stage of the process: during exploration seismic surveys, drilling, production and decommissioning. The effects of these different sources of underwater noise on marine mammals are discussed. The use of explosives for underwater cutting and demolition during the decommissioning of platforms and installations may pose a serious threat to some marine mammals. However, current understanding of the effects of noise on marine mammals is rudimentary. The effects of pollution on seals and cetaceans are discussed, including the effects of oil spills. The diseases to which they are subject are briefly discussed, as are non-oil management issues such as fisheries bycatch.

This report is a contribution to the Strategic Environmental Assessment (SEA6) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report assesses the socio-economic implications of further oil and gas licensing the SEA 6 area. The Department of Trade and Industry provided scenarios of possible exploration and development activity in the area and these scenarios were converted into optimistic and pessimistic scenarios. They were then used to produce forecasts of: oil and gas production; oil and gas reserves; expenditure; employment; and tax revenues. The implications for existing facilities in the area are discussed and the potential social impacts. An underpinning report, Economic and Social Baseline Study, is also available.

As part of the Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment (SEA2), this report reviews pockmarks in the North Sea. Pockmarks frequently contain unusual densities of fish, typically large gadoids such as cod, torsk and ling. High densities of fish otoliths have been found in one North Sea pockmark. The existence of cemented sediment in the base of pockmarks can provide a refuge for fish and a hard substrate for colonisation by epifauna such as anthozoa. Deep active pockmarks, such as the three studied in block 15/25, are known to contain species dependent on high sulphide concentrations, originating from seepage or enhanced sedimentation. Some of these species are not found elsewhere in the open North Sea. The 20 m deep "Scanner" pockmark in block 15/25 is the only pockmark in the UK sector of the North Sea whose biology has been studied in detail. It is the only known habitat of the gutless nematode Astononema southwardorum.

This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change) and deals with the shellfish resources and their commercial fisheries within SEA7. Exploited species of shellfish are found in the SEA7 zone occupying all types of habitat and distributed over a considerable range of depths, from the littoral zone down to 1000m. These species provide important fisheries and make vital contributions to the economy of remote communities on the west coast of Scotland. The main species reviewed in this report are: Norway lobster; European Lobster; Crawfish; Edible crab; Velvet swimming crab; Shore crab; Red crabs; Giant scallop; Queen scallop; Cockle; Common mussel; Razor shells; Whelks; Periwinkle

This report is a contribution to the Strategic Environmental Assessment (SEA3) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report is a synthesis of information on human activities which might have an impact on, or themselves be affected by, further oil and gas developments in the SEA3 area of the North Sea. The activities include shipping, energy (both existing oil and gas developments and renewable energy), telecommunications, military activities, waste disposal, dredging and aggregate extraction, marine archaeological sites and wrecks. The SEA3 area hosts a wide variety of different users. Some have been there for centuries, others are more recent arrivals. Among the older industries and activities are fisheries, ports and shipping, military activities and sea bathing. The offshore oil and gas industry has developed into a major player in the North Sea since the late 1960s, with considerable infrastructure of pipelines and coastal gas terminals in the SEA3 area. The number of submarine telecommunication cables across the North Sea has grown enormously in the past ten years, with the advent of the fibre optic cable and the growth of the Internet and e-commerce. The next twenty years may see considerable development of offshore wind farms in the SEA3 area.

As part of the Department of Trade and Industry (now Department of Energy and Climate Change) Strategic Environmental Assessment for Area 6 (SEA6) an environmental survey was carried out from Kommandor Jack during October 2003. The aim of the survey was to acquire seabed and water samples for biological, physical and chemical analysis together with video and digital stills photography to ground-truth the geophysical data ans enable a general characterisation of seafloor habitats and community types present within a number of offshore areas containing pockmarks and shallow gas seeps within the Irish Sea. The areas surveyed were: St Georges Wall; Yuan's Pockmarks; Pisces Reef; Texel 11, Codlings Extension; Harvey's Trench; Texel 10. This report provides a log of the field sampling work undertaken.

This data report contains the results of the analysis of sediment samples collected by Geotek on behalf of the Department of Trade and Industry (now Department of Energy and Climate Change) as part of the Strategic Environment Assessment SEA1 (White Zone) environmental sampling programme conducted from RRS Charles Darwin in summer 1999 (cruise 119C leg 2). The analyses undertaken includes total organic carbon and total organic nitrogen, particle size distribution (including silt, clay, silt/clay, carbonate and organic matter content), total and aliphatic hydrocarbon content); 2 to 6 ring polynuclear aromatic hydrocarbons (PAH) content and metal oxides and heavy metal content.

This report is a contribution to the Strategic Environmental Assessment (SEA4) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report describes the field of mud diapirs in the northern part of the SEA4 area, known as the Pilot Whale Diapirs, which were mapped during a multibeam survey carried out in 2002. A diapir is a fold or dome caused by more plastic rocks at depth, such as salt or mud, intruding overlying denser rocks, generally driven by their own buoyancy. Sometimes a diapir breaks through to the seafloor. The diapir field extends over an area some 60 km across, creating a very variable seabed terrain. The largest diapirs have produced elevations at the seafloor of more than 120m. The largest diapirs in the group are thought to have intruded to the seafloor from 500m or more beneath it. The evidence suggests that the diapirism was initiated between 5 and 1 million years ago, but it does not appear to be continuing at the present time.