| Computer Code: |
KPSC |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Guadalupian Epoch (PUG)
— Lopingian Epoch (PUL) |
| Lithological Description: |
The Kupferschiefer Formation is typically composed of dark grey or dark brown silty, fissile mudstones, which are locally black and carbonaceous. The shales are variably calcareous, and they are commonly micaceous in the Inner Moray Firth. In the Argyll Field, the Kupferschiefer Formation is composed of dark grey dolomitic mudstones that are sapropelic, dolomicritic, well indurated, thinly laminated and subfissile, and contain stringers and veins of pyrite (Bifani, 1985). The formation is characterized by high gamma-ray values, and typically by low velocities, at least in the upper part. |
| Definition of Lower Boundary: |
Whether the Kupferschiefer Formation rests conformably on Lower Permian desert sediments (Auk, Findhorn and Fraserburgh formations), or locally oversteps these onto pre-Permian strata, the base of the highly radioactive mudstones is a sharp wireline-log break in all wells. |
| Definition of Upper Boundary: |
Over the Inner Moray Firth (e.g. 12/29-2), the top of the Kupferschiefer Formation is defined by a sharp downward change from sandstone (Bosies Bank Formation) or, rarely, from anhydrite (Turbot Anhydrite Formation) to mudstone, and is marked by a rapid downward increase in gamma-ray values. Elsewhere in the Northern Permian Basin, its top generally corresponds to a transition from dolomite or dolomitic limestone (Halibut Carbonate Formation) to mudstone. The lithological and wireline-log transitions are typically gradational, with the boundary in most sections being best located at a relatively sharp downward decrease in velocity (e.g. 15/26-1, 21/11-1). The boundary is more clearly transitional where the formation is expanded (e.g. 20/2-1). |
| Thickness: |
The formation is generally less than 3 m thick. Exceptionally, the formation is between 10 m and 15 m thick in parts of the Dutch Bank and East Shetland basins, and it is up to 20 m thick locally in the South Halibut Basin. |
| Geographical Limits: |
The Kupferschiefer Formation is distinguished on wireline logs by its very high gamma-ray, low-velocity log response. The absence of these distinctive log features indicates that the formation is locally thin or absent along the northern flank of the Mid North Sea High, in the western Inner Moray Firth, and along the western flank of the South Viking Graben. Such areas appear to have retained positive relief during the Late Permian, Zechstein transgression. The Kupferschiefer Formation is widely developed elsewhere in the Northern Permian Basin. |
| Parent Unit: |
Zechstein Group (ZG)
|
| Previous Name(s): |
Kupferschiefer Formation [Obsolete Code: Use KPSC]
(KUPF)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Reference Section |
North Sea well 12/29- 2: 995-1001 m (3263-3283 ft) (Cameron, 1993). |
| Reference Section |
North Sea well 15/26- 1: 3131-3132.5 m (10272-10277 ft) (Cameron, 1993). |
| Reference Section |
North Sea well 20/02- 1: 3906-3919 m (12815-12859 ft) (Cameron, 1993). |
| Reference Section |
North Sea well 21/11- 1: 3164-3165 m (10382-10385 ft) (Cameron, 1993). |
| Reference Section |
North Sea well 30/16- 1: 2373-2375 m (7786-7792 ft) (Cameron, 1993). |
| Reference(s): |
| Bifani, R. 1985. A Zechstein depositional model for the Argyll field. 11-118 in The role of evaporites in hydrocarbon exploration. Taylor, J C M et al. (editors). JAPEC Course Notes No. 39. |
| 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. |
| Glennie, K W. 1990. Lower Permian - Rotliegend. In: Glennie, K W (ed.) Introduction to the Petroleum Geology of the North Sea, Blackwell Scientific Publications, p. 120 - 152. |
| 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. |
| Taylor, J C M. 1990. Upper Permian-Zechstein. In: Glennie, K W (ed.) Introduction to the petroleum geology of the North Sea, 153-190. Blackwell Scientific Publications, Oxford. |
| Smith, D B. 1980. The evolution of the English Zechstein basin. In: Fuchtbauer, H, and Peryt, T M (eds.) The Zechstein basin with emphasis on carbonate sequences. Contributions to Sedimentology 9, 7-34. |
| Johnson, H, Warrington, G and Stoker, S J. 1994. 6. Permian and Triassic 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. |
| Cameron, T D J. 1993. 4. Triassic, Permian and pre-Permian 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. |
| Waters, C N, Gillespie, M R, Smith, K, Auton, C A, Floyd, J D, Leslie, A G, Millward, D, Mitchell, W I, McMillan, A A, Stone, P, Barron, A J M, Dean, M T, Hopson, P M, Krabbendam, M, Browne, M A E, Stephenson, D, Akhurst, M C, and Barnes, R P. 2007. Stratigraphical Chart of the United Kingdom: Northern Britain. (British Geological Survey.) |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
