Bedrock summary lithologies across the UK Continental Shelf (2014 Version)

The Bedrock Summary Lithology Factor Map has been derived from DiGRock250k by grouping bedrock lithologies into the following categories: Class1 - Igneous, Class 2 - Tertiary Sandstone and Limestone, Class 2.5 - Tertiary Sandstone and Limestone Interbedded, Class 3 - Tertiary Mudstone, Class 4 - Mesozoic Sandstone and Limestone, Class 4.5 - Mesozoic Sandstone and Limestone Interbedded, Class 5 - Mesozoic Mudstone, Class 6 - Chalk, Class 7 - Metamorphic, Class 8 - Palaeozoic Sedimentary. Class 1 was chosen to cover any igneous rock (granite, lava). These are frequently very strong and anisotropic in their physical properties. This class excludes tuffs as these are considered sedimentary rocks. There are no time constraints on this class as granites of Tertiary age have comparable properties to those emplaced during the Palaeozoic. Some igneous rocks such as lavas may have weathered horizons often reflecting environmental conditions when the rocks were created. Class 2 covers sands and sandstones and only a few limestones (e.g. Bembridge Limestone). Class 6 comprises chalks. This bioclastic product was separated out from other sedimentary rocks due to its easy recognition, its extensive occurrence offshore and the difficulties it has posed to pile driving for monopile wind turbines. The class occurs within both the Mesozoic and Tertiary time zones No attempt has been made to subdivide the chalk areas based on their likelihood to have flints. Experience suggests that flints can impose a constraint on foundation installation and these vary depending on basin and age. Some sediments in DigRock are described as Permo-Trias sandstones and mudstone and therefore would straddle Classes 4.5 and 8. As the classification scheme is intended as rapid attempt to summarise the strength of the rocks it was decided that such sediments are closer to the Mesozoic than most of the Palaeozoic and classes 4, 4.5 and 5 should be considered for rocks that are described as Permo-Trias. In the light of that, DigRock class PUND-MDGYAN was also moved into Class 4. It was noted that there was inconsistency in the descriptions of offshore extensions of the country rock north and south of the Cornubian peninsular. To the south the sediments are described as slates whereas to the north they are described as Sandstones and mudstones. Hence they fall into differing categories, the former as class 7 metamorphic and the latter as class 8 Palaeozoic sedimentary.

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

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