Tare Formation (Tareformasjonen)

(From NPD Bulletin no. 4)

Rogaland Group


From the Norwegian name for algae or sea tangle. The formation corresponds to the informal Alstahaug formation or H5-2.

Well type section

Well 6507/12-1 (Statoil), coordinates 65°07'01.62"N, 07°42'42.61"E, from 1884 m to 1826 m (Fig. 36). No cores.


58 m in the type well.


Dark grey, green or brown claystones with some thin sandstone stringers show a variable content of tuff.

Basal Stratotype

The base is defined by an increase in tuff content. Consequently the sonic log shows a decrease in interval transit time and an increase in density log readings.

Lateral extent and variation

The Tare Formation is ubiquitous except near the crest of the Nordland Ridge. The tuff content decreases southwards.


Late Paleocene.

Depositional environment

These sediments were deposited in a deep marine environment.


The Tare Formation is similar in both age and lithology to the Balder Formation (Deegan & Scull, 1977) in the North Sea.

home previous page