1998-present Inter-Organisation UK Benthos Database series https://portal.medin.org.uk/portal/start.php?tpc=010_c25edeeb492d845621e3db3d997fc7e9 Offshore environmental impact surveys have been carried out by oil and gas operators in the North Sea since 1975, initially as part of corporate environmental management programs and latterly as regulatory requirement. Routine monitoring of the area around the installations to confirm impact hypotheses of the seabed and check the general health of the marine environment is now endorsed in UK Regulations notably under The Offshore Chemicals Regulations 2002. Monitoring surveys have traditionally been carried out along one or more transects leading away from the installations and following the prevailing current direction. Collection of sediment samples were taken at stations set at varying distances, 500, 800, 1200, 2500 and 5000 meters from the platform along the transects. Sample from reference stations located at 8 to 10 km from the installations would also be collected. The samples would then be analysed for hydrocarbons and metals content and to investigate the seabed biological communities. It is these biological data that are presented in this dataset. This monitoring strategy is designed to measure gradients of environmental effects in the vicinity of the platform. Between 1975 and 1998, it is estimated some 520 seabed surveys were carried out. However, a lack of consistency and standardization in the way these surveys were conducted has led to difficulty in establishing long-term environmental effects. To that purpose, Oil and Gas UK funded a project with the aim of collating and reviewing all seabed monitoring data collected by the UK oil and gas industry from 1975 to 1998. The Oil and Gas UK seabed environmental review was carried out in 3 phases. Phase1. Compilation of an inventory of surveys carried out in the UK sector. Phase2. Production of database files containing detailed biological, chemical and geographical data. Phase3. Examination of the extent of contamination from offshore exploration and appraisal activities and impacts on the biota, and attempt to determine any large-scale trends over wider geographical areas. The final phase was completed in April 2001. Today, techniques have evolved and the focus is more on wide-scale baseline environmental monitoring at a pre-operational stage. This involved screening the development area for any potential ecologicall important habitats and species using side-scan and or multi beam sonar and swathe bathymetry techniques. 19990101 20111010