BGS Seabed Geology: Offshore East Anglia version 1.0

The BGS Seabed Geology: Offshore East Anglia digital map provides detailed and accurate characterisation of the seabed geology, based on seabed and shallow-subsurface data. This dataset incorporates three complementary map components (Substrate Geology, Structural Geology, and Geomorphology), provided as discrete layers for viewing within a Geographic Information System (GIS). The bedrock geology of the mapped area comprises Cretaceous age Chalk Group sedimentary rocks. These rocks crop out extensively at seabed across the southern and central parts of the dataset forming an extensive bedrock platform and Europe’s largest known offshore chalk reef. This reef has been designated the Cromer Shoal Chalk Beds Marine Conservation Zone (MCZ) owing to the range of unique floral and faunal habitats that it supports. The Chalk Group is covered across the central (partly) and southern parts of the dataset by natural superficial deposits that accreted during the Quaternary. These include preglacial delta bottom-set (Westkapelle Ground Formation) and delta top-set (Yarmouth Roads Formation); and glacial sediments and landforms that were deposited and formed during at least two separate phases of glaciation that inundated parts of the southern North Sea and adjacent East Anglia during the Middle Pleistocene (Anglian / Elsterian) and Late Pleistocene (Late Devensian / Late Weichselian). Collective geological evidence includes extensive areas of out-cropping subglacial till; the presence of largely concealed and infilled over-deepened (>100 m deep) subglacial tunnel valleys, ice-marginal moraines, and a glacially disrupted chalk surface that includes the development of incised meltwater channels, detached and transported glacitectonic bedrock rafts and megablocks. Post-glacial environments from the Late-Pleistocene – Holocene (prior to marine inundation) included fluvial and estuarine deposition, that together with variable infill of late-glacial valleys are included within the Botney Cut Formation. Holocene marine transgression flooded the region, with shallow marine sedimentation active through modern times resulting in the variable cover of unconsolidated marine sediments, as well as the distribution of extensive current-induced bedforms, e.g., sediment banks, sediment waves and fields of mega ripples which are recorded within the Seabed Geomorphology dataset. Each theme is provided as distinct layers for viewing within a Geographic Information System (GIS). The “Substrate Geology” layer shows the distribution of bedrock and unlithified superficial deposits present at the seabed (below a thin veneer of seabed sediments, ‘one-metre principle’ described below) as a series of polygons; The “Structural Geology” layer represents the structural features observed at rockhead as a polylines layer, and “Geomorphology” theme consists of points, polylines, and polygons layers to portray the main seabed morphological and geomorphological features.

Date (Creation): 2024-02

Citation identifier: http://data.bgs.ac.uk/id/dataHolding/13608247

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Distributor
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Point of contact
British Geological Survey	Enquiries	not available	Distributor
British Geological Survey	Enquiries	not available	Point of contact

Maintenance and update frequency: Not planned

GEMET - INSPIRE themes, version 1.0

Geology

BGS Thesaurus of Geosciences

Geomorphology
Surficial geology
Mapping
Structural geology
Bed rock
Sea floor
UK Location (INSPIRE)

dataCentre

UK Location (INSPIRE)

Keywords

NERC_DDC

Access constraints: Other restrictions

Other constraints: licenceOGL

Other constraints: Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced NERC materials "Contains NERC materials ©NERC [year]"

Use constraints: Other restrictions

Other constraints: The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Other constraints: Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced NERC materials "Contains NERC materials ©NERC [year]"

Spatial representation type: Vector

Language: English

Topic category

Geoscientific information

Geographic identifier: UK CONTINENTAL SHELF [id=121701]
British Geological Survey Gazetteer: Geographical hierarchy from Geosaurus 1979 creation

End date: 2024-02 Before

Unique resource identifier: WGS 84 / UTM zone 31N (EPSG::32631)

Distribution format

Name	Version
ESRI Shapefile (.shp)
ESRI layer file (.lyrx)

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Distributor

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	not available	Distributor

OnLine resource

Protocol	Linkage	Name
	https://mapapps2.bgs.ac.uk/geoindex_offshore/home.html	GeoIndex Offshore Homepage

OnLine resource

Protocol	Linkage	Name
	https://doi.org/10.5285/98d92cef-88da-40a9-8a01-621d4e607152	Digital Object Identifier (DOI)

Hierarchy level: Dataset

Conformance result

Title: INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology

Date (Publication): 2011

Explanation: See the referenced specification

Pass: No

Conformance result

Title: 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

Date (Publication): 2010-12-08

Explanation: See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Pass: No

Statement: The delineation and classification of the geological substrate units were based primarily on what can be observed and interpreted from the multibeam echo-sounder (MBES) bathymetry data collected during the Civil Hydrography Programme (CHP) surveys managed by the Maritime and Coastguard Agency (MCA). CHP data are made available via an Open Government Licence. Within the Offshore East Anglia area, mapping utilised 6 contiguous high-resolution multibeam datasets: • CHP surveys - Cromer Shoal Chalk Beds Multibeam Survey CSCB_3_2014 (2014) - HI1515 Haisborough Sand to Outer Dowsing Channel Area (2018) - HI1673 Sheringham Shoal (2020) - HI1447 Blakeney Overfalls (2014) - HI1427 The Would North, Centre and South (2015) - HI1428 Newark Banks to Cross Sands (2014) MBES backscatter, physical samples (e.g., grabs, cores, and boreholes), seismic data, academic and publicly accessible industry literature, and previous BGS mapping (e.g.,1:250k maps) were also used to further inform the geological interpretation. The geological analysis, interpretation, and mapping were carried out for presentation at 1:10,000 scale in 2021-23 by Jonathan Lee, Dayton Dove and Nicola Dakin. Important contributions including scientific (and technical) advice and review were provided by: Andrew Finlayson, Margaret Stewart and Emrys Phillips. The dataset compilation was done by Joana Gafeira. The analysis, interpretation and mapping methodology are described in more detail in the user guide for this dataset OR/24/003.