Narve Formation (Narveformasjonen)

updated to follow: Stratigraphic Guide to the Cromer Knoll, Shetland and Chalk Groups of the North Sea and Norwegian Sea. Felix M. Gradstein & Colin C. Waters (editors), Mike Charnock, Dirk Munsterman,  Michelle Hollerbach, Harald Brunstad, Øyvind Hammer & Luis Vergara (contributors). Newsletter on Stratigraphy, vol 49/1 pp71-280, 2016

Chalk Group


The definition of the Narve Formation in the Central Graben is after Fritsen & Riis (2000: ‘A revised chalk lithostratigraphic nomenclature’; NPD Report, unpublished) (see Table)


After the Norse god Narve, who was the son of Loke and Sigyn.


Lithofacies associated with the crestal biofacies on Valhall are typically (textural) mudstones and wackestones. Those associated with the “shallow water” pelagic biofacies are varied, though typically bioturbated to laminated chalks or interlaminated chalks and clays indicative of slow sedimentation. Those associated with the “deep water” pelagic biofacies are typically massive chalks. Recognition of allochthonous as against autochthonous chalks is difficult, for which high-resolution study is desirable of the paleobathymetry of foraminifera. Lithofacies in core from the 2/8-A-1 well include bioturbated chalks with Chondrites, Planolites and Zoophycos, and also allochthonous debris flows and slumps with micritic matrices and polymict/non-chalk clasts, indicating affinity with the “shallow water” and “deep water” pelagic biofacies of the Valhall structure respectively. Allochthonous chalks are also observed in core from Mona-1.


The thickness of this formation ranges from zero to a few hundred meters in the study wells. It is thin (typically less than 100 m thick) in wells on structural highs such as Valhall-Hod and Tor in the Norwegian Sector, and thickest in wells in basinal lows such as that in the Roar area in the Danish Sector, and in the northern and western depocenters in the Norwegian Sector.

Geographical distribution

The formation is present in the Central Graben in the Norwegian and Danish Sectors. It is absent in the 2/2 wells in the Norwegian Sector and in the Lulu-1 well in the Danish Sector. The formation is eroded on crests of structures.


Type well

Well name: 1/3-8 (Norwegian Sector)

4520-4337 m MD.


Reference Well

2/8-A-1, 2581.5 - 2501.5 m MD.

Upper and lower boundaries

Upper Boundary

Picked primarily on seismic and biostratigraphic criteria. The seismic criterion is an onlap surface. The biostratigraphic criterion is penetration of local nannozone UC11.

Lower Boundary

Picked primarily on biostratigraphic and log criteria. The biostratigraphic criterion is penetration of local microzone FCS13 or local nannozone UC3. The log criterion is a downhole gamma increase indicating penetration of the shales of the Blodøks Formation.

Well log characteristics

The Narve Formation has been penetrated in many wells in the Valhall area (Lindesnes Ridge) and in the Ål Basin to the west of the ridge. The gamma log patterns of these wells correlate well in this area, and a detailed correlation of different subzones is possible. A zone of clean chalk with consistently low gamma values, overlain by a gamma spike, is situated in the middle of the Narve Formation. This zone (informally named Hod4 by BP) constitutes an important reservoir in the Valhall Field, and it can easily be recognised on the logs. However, its biostratigraphic age is not consistent between the wells, and it is possible that the “Hod4” subzone is diachronous.


Microzones FCS14-FCS18pp; nannozones UC4-UC11.


Latest Cenomanian-earliest Santonian (for practical purposes, Turonian-Coniacian).

Depositional environment

Variable “shallow water” and “deep water” pelagic environments are listed in well completion reports.


After Fritsen, A. & Riis, F. 2000. A revised chalk lithostratigraphic nomenclature; NPD Report, unpublished)