Rogn Formation (Rognformasjonen)
(Based on NPD Bulletin no. 4)
The Norwegian word for spawn or hard roe. The formation corresponds to the
informally used Frøya formation.
Well type section
(Shell), coordinates 64°21'55.39"N, 07°47'21.76"E, from 1670 m to 1621 m
(Fig. 22). Three cores, recovery 35.5 m, including the base.
49 m in the type well.
The formation shows a coarsening upward sequence from siltstones and
shales to sandstones which constitute the bulk of the unit.
The Rogn Formation is developed within the
Draupne Formation in the type
well. The lower boundary is defined at the base of a gradual decrease in
the gamma ray log and at a sharp decrease in interval transit time shown
by the sonic log (Fig. 21).
Lateral extent and variation
The formation is developed in the Draugen Field area, where it thins
laterally away from the type well.
Oxfordian to Kimmeridgian.
The formation's sandstones are interpreted as
shallow marine bar deposits.
There are no known comparable units in surrounding areas.