Fensfjord Formation (new)
(From NPD Bulletin no. 3)
Viking Group
Name
After a fjord on the west coast of Norway,
adjacent to the type area in Quadrant 31.
Well type section
Norwegian well 31/2-1
(Shell) from 1594.5 m to 1741.5 m, coord N60°46' 19.16", E03°33' 15.87", (Fig. 21).
Well reference section
None at present.
Lithology
The formation consists of sandstones, grey-brown in colour, fine to medium grained, well sorted and moderately friable to consolidated. Calcite cemented sandstones occur in bands containing common bioclastic material. In the type well it is often carbonaceous and occasionally micaceous. Minor shale intercalations occur throughout. The formation has a "serrate" log character, composed of 3-5 m thick units arranged in several cycles.
Boundaries
The formation has an overall higher gamma-ray intensity and larger FDC-CNL
separation than the underlying Krossfjord
Formation. The top of the Fensfjord Formation is characterized by a
transition in the gamma-ray log from a high intensity, serrate log shape to
a high intensity but smooth outline in the overlying
Heather Formation.
Distribution
The formation has only been clearly recognized in the Troll Field area.
Age
Callovian.
Depositional environment
The formation was deposited in a coastal shallow marine environment.