Krossfjord Formation (new)
(From NPD Bulletin no. 3)
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 1741.5 m to 1880 m, coord N60°46'19.16", EO3°33'15.87", (Fig. 21).
Well reference section
None at present.
The formation consists of sandstones, light grey-brown in colour, medium to coarse grained, well sorted, and loose to very friable. Occasionally calcite cemented streaks occur. The lower portion of the Krossfjord Formation is slightly argillaceous and carbonaceous with minor shale intercalations.
In the type well the formation overlies the lower part of the
Heather Formation. It has a "blocky" log character
and is the first continuous thick sandstone unit above the
Brent Group. The base of the formation is shown by
the underlying reduction in gamma-ray intensity and FDC-CNL separation.
The top is characterized by the change to the serrate gamma ray log motif
of the overlying Fensfjord Formation and an
overall upward increase in gamma ray intensity.
The formation has only been clearly recognized in the Troll Field area.
The formation was deposited in a coastal shallow marine environment.