| Computer Code: |
DVSA |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Berriasian Age (KR)
— Valanginian Age (KV) |
| Lithological Description: |
The member comprises sandstones with interbedded mudstones. Sandstones are typically pale grey to green-grey or grey-green (locally brown grey), fine- to medium-grained and argillaceous. They are variably cemented by calcite or anhydrite. Interbedded mudstones are grey to grey-green, sandy or silty and slightly to moderately calcareous. |
| Definition of Lower Boundary: |
The base of the member is typically defined by a downward change from pale grey, calcareous sandstone or interbedded sandstone and mudstone to darker grey, less calcareous sandstones (Fulmar Formation) (e.g. 28/8b-1) or Triassic red beds (e.g.29/25-1) (Redefined by Johnson and Lott, 1993). |
| Definition of Upper Boundary: |
The upper boundary is defined by a downward change from grey or red calcareous mudstones to pale grey, variably calcareous sandstones. On wireline logs, it is typically marked by a downward decrease in gamma-ray values (Redefined by Johnson and Lott, 1993). |
| Thickness: |
Up to 41 m. |
| Geographical Limits: |
North Sea Quadrant 29. |
| Parent Unit: |
Valhall Formation (VALH)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
North Sea well 29/25- 1 at 2423-2482 m below KB (Johnson and Lott, 1993). |
| Reference Section |
North Sea well 29/08b- 1 at 3336-3351.5 m (Johnson and Lott, 1993). |
| Reference Section |
North Sea well 29/24- 1 at 1733-1746.5 m (Johnson and Lott, 1993). |
| Reference(s): |
| Deegan, C E and Scull, B J. 1977. A standard lithostratigraphic nomenclature for the Central and Northern North Sea. Report of the Institute of Geological Sciences, 77/25; NPD Bulletin No.1. |
| Rhys, G H. 1974. A proposed standard lithostratigraphic nomenclature for the southern North Sea and an outline structural nomenclature for the whole of the (UK) North Sea. Report of the Institute of Geological Sciences, 74/8. |
| Johnson, H and Lott, G K. 1993. 2. Cretaceous of the Central and Northern North Sea. In Knox, R W O'B and Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. British Geological Survey, Nottingham. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
