93f9fcbc-ada7-4fe4-8738-2d0b4511838f English series series 2026-09-01T12:18:16 MEDIN 3.1.2 geoscientificInformation Sedimentary structure SeaDataNet Parameter Discovery Vocabulary 2026-06-19 revision Geotechnics SeaDataNet Parameter Discovery Vocabulary 2026-06-19 revision Consenting The Crown Estate Renewable Energy Development Phases 2012-05-15 revision Agreement for Lease Area The Crown Estate Renewable Energy Development Areas 2012-05-15 revision Geology GEMET - INSPIRE themes, version 1.0 2009-07-31 revision SeaDataNet sea areas 2012-11-07 revision English Channel SeaVoX Vertical Co-ordinate Coverages 2020-05-21 revision soil and sediment 2004-03-31T23:00:00 2005-03-30T23:59:59 1.34879217206949 1.6758136933659 51.5650393531118 51.7655320971418 0.00 -23.00 TCE-976 Marine Data Exchange 2004-2005, HydroSoil, Gardline Geosciences & Osiris Projects, London Array, Ground Investigation Survey Ground Investigation Survey 2005-01-01T00:00:00 creation 2022-05-23T11:56:50 publication English London Array Limited commissioned geophysical and geotechnical surveys for the proposed offshore wind farm in the outer Thames Estuary, comprising up to 300 turbines and a 46.5km buried electrical cable connection. Conducted by Osiris Projects and Gardline Geosciences, with oversight by Hydro Soil Services, the surveys employed sonar, vibrocores, Cone Penetration Tests, bathymetric methods, physical sediment sampling, and analysis of geophysical charts and reports to assess seabed conditions and recommend cable burial strategies. Findings revealed variable seabed compositions, sediment mobility, biogenic gas presence, and multiple hazards, including magnetic anomalies and debris. Recommended burial depths range from 0.6m to 2.0m, with jet trenching or ploughing for unconsolidated sediments and pretrenching for stiff clay, emphasizing the importance of detailed risk assessment, site-specific geological considerations, and robust burial protection to mitigate threats such as fishing and anchoring. Origin: Gardline Geosciences There will be no limitations when published on the Marine Data Exchange otherRestrictions Data Must be used in accordance to the Marine Data Exchange's Terms of Use: https://www.marinedataexchange.co.uk/content/info/terms-of-use otherRestrictions The Crown Estate +44 020 7851 5000 enquiries@thecrownestate.co.uk custodian Gardline Geosciences Ltd 01962 868626 geotechnical.web@gardline.com originator The Crown Estate +44 020 7851 5000 enquiries@thecrownestate.co.uk distributor RWE support@rwe.com owner notPlanned Documents https://www.marinedataexchange.co.uk/details/TCE-976/summary A link to the web service or dataset. https://www.marinedataexchange.co.uk A link to the general host site. Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08T00:00:00 publication Conformity with the Commission Regulation (EU) No 1089/2010 was either not relevant to this dataset or not a requirement of the Marine Data Exchange for the creation and submission of this dataset; therefore, conformity has not been assessed and cannot be declared False series Osiris Survey undertook a geophysical survey of the proposed route between April and August 2004. The Osiris survey comprised bathymetric, side scan sonar, magnetometer and sub-seabed profiling. The results are presented in the alignment chartsRef1. Gardline undertook a geotechnical survey with vibrocores and Cone Penetration Tests (CPTs). A total 32 vibrocores and 24 CPTs were applicable to the proposed cable route. Full details of the geophysical and geotechnical surveys carried out are given in the Gardline reportsRef2. Following completion of the fieldwork, a programme of laboratory testing was undertaken. The testing relevant to the trenching comprised: Particle Size Distribution (PSD) analysis Moisture Content Atterberg Limit determinations Hand Shear Vanes The results of the geophysical and geotechnical surveys have been correlated and the route has been divided into sections dependant upon seabed features and geology. These sections are detailed in the Cable Route Summary Tables in Appendix A. The tables detail the seabed features and the shallow geology as well as highlighting any other features that may pose a hazard to trenching such as magnetic anomalies and sonar contacts. The Crown Estate enquiries@thecrownestate.co.uk pointOfContact EPSG Geodetic Parameter Registry 2022-11-29 revision WGS 84