Computer Code: |
FRIS |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Early Eocene (GEE)
— Early Eocene (GEE) |
Lithological Description: |
Thick-bedded, clean, poorly consolidated, fine, to medium grained, locally coarse-grained sandstone, with sparse glauconite and carbonaceous particles. Sporadic thin calcite-cemented layers are present in most sections, as are thin beds of grey to grey-green, variably silty mudstone. Gamma-ray log profiles are typically 'blocky' (e.g. 10/1-1 A), but are locally serrated (e.g. 3/30a-3). |
Definition of Lower Boundary: |
The Frigg Sandstone Member is underlain by a thin unit of grey-green or variegated Horda mudstone that separates it from the underlying dark grey mudstones of the Balder Formation. |
Definition of Upper Boundary: |
The Frigg Sandstone Member is overlain by grey-green or grey-red Horda Formation mudstone. A distinct high-gamma spike is present at, or shortly above, the boundary in many sections (e.g. 3/30a-3). |
Thickness: |
Thicknesses are highly variable, and exceed 300 m in places. |
Geographical Limits: |
The Frigg Sandstone Member is restricted to Quadrants 10 and 4 and the southeastern part of Quadrant 3, extending eastwards into the Norwegian sector. A narrow ribbon of sandstone is inferred to extend southeastwards into Quadrant 9. |
Parent Unit: |
Horda Formation (HORD)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Reference Section |
North Sea well 10/01- 1A: 1876-2083 m (6155-6834 ft) (Knox and Holloway, 1992). |
Reference(s): |
Knox, R W O'B and Holloway, S. 1992. 1. Paleogene 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. |
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. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |