The Cumbrian Coast Group is a

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

lithostratigraphic Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are primarily igneous ...

group A group is a number of persons or things that are located, gathered, or classed together. Groups of people * Cultural group, a group whose members share the same cultural identity * Ethnic group, a group whose members share the same ethnic iden ...

(a sequence of

rock strata In geology and related fields, a stratum (: strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ...

) which occurs in the western part of

Cumbria Cumbria ( ) is a ceremonial county in North West England. It borders the Scottish council areas of Dumfries and Galloway and Scottish Borders to the north, Northumberland and County Durham to the east, North Yorkshire to the south-east, Lancash ...

in northern

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

Distribution and stratigraphy

The group outcrops near

Whitehaven Whitehaven is a town and civil parish in the Cumberland (unitary authority), Cumberland district of Cumbria, England. It is a port on the north-west coast, and lies outside the Lake District National parks of England and Wales, National Park. ...

on the Cumbrian coast and beneath the

Vale of Eden The Vale of Eden is formed by the course of the River Eden, one of the major rivers of Northwest England. It is however of much greater extent than the actual valley of the river, lying between the Cumbrian Mountains (more usually referred to a ...

. It comprises the St Bees Evaporite and the overlying St Bees Shale Formation which are between 0 and 100m and 0 and 215m thick respectively. The lower formation sits atop the mixed lithology

breccia Breccia ( , ; ) is a rock composed of large angular broken fragments of minerals or Rock (geology), rocks cementation (geology), cemented together by a fine-grained matrix (geology), matrix. The word has its origins in the Italian language ...

known as Brockram. It is also found beneath the

Irish Sea The Irish Sea is a body of water that separates the islands of Ireland and Great Britain. It is linked to the Celtic Sea in the south by St George's Channel and to the Inner Seas off the West Coast of Scotland in the north by the North Ch ...

where the Barrowmouth Mudstone Formation is the equivalent of the St Bees Shale Formation. The Group can achieve thicknesses in excess of 300m here.

References

Geology of Cumbria Permian System of Europe {{UK-geology-stub