| Computer Code: |
FRNE |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Courceyan Substage (CF)
— Namurian Stage (CN) |
| Lithological Description: |
The term Farne Group is introduced here for the Dinantian to early Namurian succession, largely of lacustrine, fluvial, coal-measures, and 'Yoredale' facies, that extends offshore from the Northumberland coast over the western crestal area and the southern flank of the Mid North Sea High. The succession continues eastwards into the Dutch sector, where it is also designated the Farne Group (van Adrichem Boogaert and Kouwe, 1993). None of the UK wells has penetrated the complete Dinantian succession.
The Farne Group rests on Upper Devonian to early Courceyan terrestrial sediments (Upper Old Red Group), the boundary being defined by the widespread appearance of dolomitic micrite beds (cementstones). In most wells, the group subcrops Upper Permian marine sediments and evaporites of the Zechstein Group. Where Namurian to early Westphalian basinal and deltaic deposits of the Whitehurst Group are also preserved beneath the base-Permian unconformity, the facies transition is diachronous. The group boundary is defined by the highest marine carbonate bed in the succession. The southern limit of the Farne Group is poorly constrained, as no wells have penetrated Dinantian strata in the central Southern North Sea area.
In the UK sector, the Farne Group is divided into four formations, three of which are named after their onshore equivalents, the Cementstone, Fell Sandstone, and Scremerston Coal groups of the Northumberland Trough (refer to George et al., 1976). The overlying Yoredale Formation is named after the Yoredale cycles which are its chief characteristic, and correlates with the Lower, Middle, and Upper Limestone groups of northeast England. Formational hierarchy has been adopted for the offshore units to conform with modern stratigraphical procedures (refer to Whittaker et al., 1991). With the exception of the Yoredale Formation, the Southern North Sea units are unlikely to be capable of subdivision. |
| Definition of Lower Boundary: |
The Farne Group rests on Upper Devonian to early Courceyan terrestrial sediments (Upper Old Red Group), the boundary being defined by the widespread appearance of dolomitic micrite beds (cementstones). |
| Definition of Upper Boundary: |
In most wells, the group subcrops Upper Permian marine sediments and evaporites of the Zechstein Group. Where Namurian to early Westphalian basinal and deltaic deposits of the Whitehurst Group are also preserved beneath the base-Permian unconformity, the facies transition is diachronous. The group boundary is defined by the highest marine carbonate bed in the succession. |
| Thickness: |
none recorded or not applicable
|
| Geographical Limits: |
none recorded or not applicable
|
| Parent Unit: |
Not Applicable (-)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| Cameron, T D J. 1993. 5. Carboniferous and Devonian of the Southern North Sea. In: Knox, R W O'B and Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. British Geological Survey, Nottingham. |
| Adrichem Boogaert, H A Van, and Kouwe, W F P (compilers). 1993. Stratigraphic nomenclature of the Netherlands: revision and update of RGD and NOGEPA. Mededelingen van Rijks Geologische Dienst 50. |
| George, T N, Johnson, G A L, Mitchell, M, Prentice, J E, Ramsbottam, W H C, Sevastopulo, G D and Wilson, R B. 1976. A correlation of the Dinantian rocks of the British Isles. Special Report of the Geological Society of London, No 7. |
| Whittaker, A, Cope, J C W, Cowie, J W, Gibbons, W, Hailwood, EA,House, M R, Jenkins, D G, Rawson, P P, Rushton, A W A, Smith D G, Thomas, A T and Wimbledon, W A. 1991. A guide to stratigraphical procedure. Journal of the Geological Society, London 148, 813-824. |
| Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E001
E002
|
