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Hardråde Formation (Hardrådeformasjonen)

(From NPD Bulletin no. 5)

Shetland Group


Named after Harald "Hardråde" Sigurdsson, a Norwegian King (A.D. 1046-1066).

Well type section

Norwegian well 30/11-3 from 2892 to 2601 m, coordinates N 60°02'38.59", E 02°32'15.47" (Fig. 36). No cores.

Well reference section

Norwegian well 31/6-2 from 968 to 978 m, coordinates N 60°34'58.24", E 03°54'55.76" (Fig. 37). Cored through the formation.


The formation is 291 m thick in the type well (30/11-3) and 10 m in well 31/6-2. It is absent on tilted fault blocks in the Troll area (e.g. well 31/2-9).


The formation consists generally of interbedded limestones and mudstones, except in the Troll area where it is thin and consists of a single limestone bed. The limestones are white or pale, moderately hard to very hard. The mudstones are medium to light grey, often silty and calcareous.

Basal stratotype

The lower boundary is towards the Kyrre Formation or an unconformity above older rocks. The boundary towards the Kyrre Formation is identified by the absence of relatively thick limestone beds in this formation and a lower content of calcareous material in the mudstone. This results in a decrease in gamma-ray intensity and an increase in velocity from the Kyrre Formation into the Hardråde Formation (Fig. 36). The formation has an unconformable lower boundary in the Troll area.

Characteristics of the upper boundary

The upper boundary is towards the Rogaland Group. When it is towards the Lista Formation it is characterised by an upward increase in gamma-ray intensity and a distinct drop in velocity due to a transition from limestones to mudstones (Fig. 36). An upper boundary towards the Våle Formation lacks the distinct drop in velocity. This is due to the presence of limestones and a more marly facies in the Våle Formation. An upper boundary towards the Ty Formation is shown by a change to sandstone.


The formation is present on the Horda Platform (Fig. 32b).

Occurrences of formation tops in wells


Late Campanian to Maastrichtian.

Depositional environment

Open marine.


The Hardråde Formation is time-equivalent with the Jorsalfare and Tor Formations of the Shetland Group (Fig. 6).

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