aba64100-c118-4de3-e044-0003ba6f30bd English dataset Mary Mowat British Geological Survey (BGS) +44 (0)131 667 1000 +44 (0)131 668 4140 offshoredata@bgs.ac.uk pointOfContact 2011-08-30 MEDIN Discovery Metadata Standard Version 2.3.5 urn:ogc:def:crs:EPSG::4326 OGP 2002 Strategic Environmental Assessment SEA3 Technical report - Geology, North Sea (Addendum to SEA2 report) 2002-08-01 publication BGS_SEA_34 British Geological Survey 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) and is an addendum to "SEA2 Technical report 008 - North Sea Geology, covering subsurface geology, sea-bed sediments, sediment mobility and seismicity." by same authors. The geology of the North Sea from the Palaeozoic era to the present day is reviewed, with reference to petroleum geology. Geological factors affect the environmental consequences of oil and gas exploitation in many different ways. For example, in the case of the Ekofisk oilfield in the Norwegian sector of the North Sea, oil production led to seafloor subsidence of a few metres due to its chalk reservoir, but production-related subsidence on this scale is atypical. The evolution of the geomorphology and composition of the shallow and seabed sediments is discussed. The distribution of mud, sand, gravel and hard substrates influence the nature of the benthos and can affect the way in which contaminants are accumulated and transported. Shallow seabed sediments support the foundations of structures ranging from platforms to pipelines. Hydrogeological conditions and the risk of pollution to aquifers are also reviewed. Paul Henni British Geological Survey (BGS) +44 (0)131 667 1000 Murchison House, West Mains Road Edinburgh EH9 3LA UK offshoredata@bgs.ac.uk custodian Department for Energy and Climate Change (DECC) +44 0300 060 4000 +44 (0) 1823 284077 Admiralty Way London SW1A 2HD UK enquiries@decc.gsi.gov.uk originator notPlanned Documents NDGO0001 Bathymetry and Elevation Lithology Sediment accumulation rate SeaDataNet Parameter Discovery Vocabulary 2011-03-25 revision Geology GEMET - INSPIRE themes, version 1.0 2008-06-01 publication crust sediment SeaVoX Vertical Co-ordinate Coverages 2008-06-01 publication The SEAs data were produced as part of the UK Department of Energy and Climate Change's Offshore Energy Strategic Environmental Assessment programme; Crown Copyright, all rights reserved. The DECC SEA must be acknowledged in any maps or publications that make use of the data. All the data files are freely available to the public. The Strategic Environmental Assessment (SEA) data portal provides free access to available data and reports which have been produced through the SEA process. The site is run and managed by BGS on behalf of the Department of Energy and Climate Change (DECC). Many files can be downloaded directly from this website. Those that are too large to download can be ordered via the website for postal delivery from BGS. BGS (NERC) has been contracted by DECC to publish SEA datasets on its behalf. All intellectual property rights (including , without limitation, copyrights, database rights and all other rights which subsist or may at any time in the future subsist in the Dataset(s)) in the Dataset(s) ('Intellectual Property Rights') are owned by DECC (formerly the Department of Trade and Industry, and the Department for Business, Enterprise and Regulatory Reform). BGS has been authorised by DECC to use SEA datasets for all purposes but on a 'not-for-profit basis'. BGS has been authorised by DECC to pass on SEA datasets to third parties so that they can use them for all purposes but on a 'not-for-profit' basis. intellectualPropertyRights 5 English environment geoscientificInformation oceans SeaVoX salt and fresh water body gazetteer 2006-01-01 revision North Sea -1.9 3.3 52.8 61.8 2002-01-01 2002-01-01 http://www.offshore-sea.org.uk/site/index.php http://www.bgs.ac.uk/data/sea/home.html Strategic Environmental Assessment (SEA) data portal The Strategic Environmental Assessment (SEA) data portal provides free access to available data and reports which have been produced through the UK Department of Energy and Climate Change SEA process. The site is run and managed by BGS on behalf of the Department of Energy and Climate Change (DECC). Many files can be downloaded directly from this website. Those that are too large to download can be ordered via the website for postal delivery from BGS. download dataset Report produced by British Geological Survey, August 2002 as part of the UK Department of Energy and Climate Change's Offshore Energy Strategic Environmental Assessment programme. This review presents a summary of published data and their interpretation from areas in the mature oil and gas areas of the UK North Sea.