The oldest Billefjorden Group is of latest Devonian to Early Carboniferous age and consists of clastic sedimentary rocks. Deposition started in the Famennian in separate, possibly
isolated troughs, but deposition became widespread through the Early Carboniferous (Steel & Worsley 1984). Most significant exposures are preserved in the Inner Hornsund, St. Jonsfjorden, Billefjorden and West Bjørnøya troughs (Fig. 2-02, Fig. 2-03).
The overlying Gipsdalen Group comprises Bashkirian through to Lower Permian strata. Lowermost clastic units of a predominantly redbed facies are found in the same troughs
as the underlying Billefjorden Group (Steel & Worsley 1984). Deposition started in the Serpukhovian and most of the troughs show an increasing marine influence, with both
evaporites and carbonates replacing the clastics through the Bashkirian and into the Moscovian. Intermediate platform and structurally high areas (Wedel Jarlsberg Land High,
Sørkapp-Hornsund High [Steel & Worsley 1984], Nordfjorden High [Cutbill & Challinor 1965]) were progressively transgressed through the Moscovian leading to the widespread development of platform carbonates. An important exception is the Inner Hornsund Trough, where clastic deposition prevailed to the latest Carboniferous.
The complex stratigraphic development of the Gipsdalen Group justifies a stratigraphic subdivision at a higher than formation rank. Such a grouping enables us to address to the
sedimentary fill of an individual trough or basin with related depositional environments. Such subdivisions had been proposed prior to the stratigraphic scheme of Cutbill &
Challinor (1965). These units had group rank, but should now be considered as subgroups of the Gipsdalen Group.
The Charlesbreen Subgroup (according to Dineley 1958), originally used for the Bashkirian-Moscovian clastic deposits of the St. Jonsfjorden area, can reasonably be extended to comprise the sedimentary fill of the entire St. Jonsfjorden Trough, so that the more or less coeval sediments of Brøggerhalvøya (NW Oscar II Land) should be
included in this unit.
The Campbellryggen Subgroup (according to Gee et al. 1952) designates the Bashkirian-Moscovian fill of the Billefjorden Trough with transitional clastic, carbonate and evaporite facies, with uppermost units onlapping areas to the east of the trough.
The Bashkirian to Lower Permian clastic fill of the third, well-defined trough, the Inner Hornsund Trough, is here collectively called the Treskelen Subgroup.
Coeval deposits on Bjørnøya and in the Eastern Ny Friesland/
Lomfjorden/Nordaustlandet area are not assigned to any subgroup, because regional distribution and affiliation with defined troughs are too poorly known.
The overlying, extensively deposited platform carbonates and evaporites that were deposited over most of Svalbard are here called the Dickson Land Subgroup.
The Upper Artinskian to Kazanian Tempelfjorden Group consists of siliceous, spiculitic platform sediments, locally interbedded with carbonates or sandstones. They have been
deposited all over Svalbard, except on the Sørkapp-Hornsund High. West of the Sørkapp-Hornsund High, another basinal area – the extent of which into present offshore areas is still unknown – existed in the late Permian.
One additional group recently recognised on the southern Barents Sea Shelf, the Bjarmeland Group, has only one thin representative formation on Bjørnøya, stratigraphically below the Tempelfjorden Group.
Since 1965, a number of minor revisions of the scheme of Cutbill & Challinor have been proposed. These are – with the exception of the two remote islands Nordaustlandet and
Bjørnøya – not shown here, but are discussed in the subsequent sections of this Chapter.
Bjørnøya (Bear Island), situated half-way between Svalbard and the mainland of Norway, provides a local exposure of the Famennian to Triassic stratigraphy of the Barents Sea Shelf margin. Early Permian faulting and westward tilting of the West Bjørnøya Trough (Fig. 2-02) resulted in westward
younging exposures of Famennian to earliest Permian formations, while the two youngest formations of Artinskian to Ufimian age unconformably overlie the tilted older
ones (Horn & Orvin 1928).
Although most of the individual formations of Bjørnøya can be correlated with contemporaneous units on Spitsbergen, the nomenclature has developed independently
(Andersson 1900; Horn & Orvin 1928; Cutbill & Challinor 1965; Krasil'ščikov & Livšic 1974; Worsley & Edwards 1976). Considering the distance from Spitsbergen, the
poorly known stratigraphy between the two islands, and distinct lithological differences in parts of the succession, there are sufficient reasons to keep separate formation names for
Bjørnøya, but apply group names from Spitsbergen as proposed by Cutbill & Challinor (1965). No subgroup names are applied to Bjørnøya because of insufficient knowledge of lateral extent and possible correlations of trough and platform
facies regimes.
The original subdivisions of Andersson (1900), adopted by Horn & Orvin (1928), have essentially been maintained by all subsequent authors. Names for the lowermost two formations were proposed by Cutbill & Challinor (1965), and for the other formations by Krasil'ščikov & Livšic (1974). Worsley & Edwards (1976) defined these formations formally, though using different names for three of them (Fig. 2-03).
The difficult communication between Russian and Western geologists at that time resulted in a situation where both name sets have to be regarded as contemporaneously developed, and no priority principle can be applied, in spite of apparently different years of publication. Both name sets are well-established in the geological literature of the respective countries. Two of the formations (Kapp Kåre/"Kobbebukta" and Miseryfjellet/"Laksvatnet" formations) are undoubtedly better exposed at the localities indicated by Worsley & Edward's names, while the third formation (Hambergfjellet/"
Alfredfjellet" Formation) is well exposed in both name-giving localities. It is recommended to use the nomenclature of Worsley & Edwards (1976) in order to keep one frequently used set of names together rather than constructing an artificial compromise.
The nomenclature recommended herein consists of the clastic Røedvika and Nordkapp formations (Cutbill & Challinor 1965) in the Billefjorden Group, while the following formations are assigned to the Gipsdalen Group: Landnørdingsvika (Krasil'ščikov & Livšic; Worsley & Edwards), Kapp Kåre (Worsley & Edwards), Kapp Hanna (Krasil'ščikov & Livšic; Worsley & Edwards) and Kapp
Dunár (Krasil'ščikov & Livšic; Worsley & Edwards). The Bjarmeland Group is represented by its only onshore unit, the Hambergfjellet Formation (Worsley & Edwards 1976). The Tempelfjorden Group is represented by the Miseryfjellet Formation (Worsley & Edwards).
The Sørkapp-Hornsund High (Steel & Worsley 1984) occupies most of the western and southern parts of Sørkapp Land on southern Spitsbergen (Fig. 1-05, Fig. 2-02). The Lower
Carboniferous Billefjorden Group was probably deposited across large parts of the area, then removed by subsequent uplift in central and eastern parts (Gjelberg 1987; Dallmann
1992), and is now preserved in its northwestern areas. It consists of the Hornsundneset Formation and the overlying Sergeijevfjellet Formation (Siedlecki 1960).
The Sørkapp-Hornsund High acted as a topographical high and a sediment source for the adjacent troughs from the Bashkirian through the Permian into the early Triassic.
To our present knowledge, neither Gipsdalen nor Tempelfjorden Group sediments were ever deposited on the high itself.
In the basinal area to the southwest of the high, thick deposits of the Artinskian to Upper Permian Tempelfjorden Group, the Tokrossøya Formation (Siedlecki 1964), occur
on the islands of Sørkappøya and Tokrossøya and on the peninsula øyrlandsodden. Underlying rocks are poorly exposed and possibly constitute an extension of the Billefjorden Group sediments from the Sørkapp-Hornsund High
(Dallmann et al. 1993).
The Inner Hornsund Trough (Gjelberg & Steel 1981; Steel & Worsley 1984) stretches from eastern Sørkapp Land across the inner part of Hornsund northwestward into Wedel Jarlsberg Land (Fig. 1-05, Fig. 2-02). Its northwestward continuation is unknown, because Late-Cretaceous and Cenozoic basement uplift removed the record. Its northeastern limit is buried below Mesozoic and Cenozoic strata. The trough is bound by the Sørkapp-Hornsund High (Steel & Worsley 1984) to the southwest.
Carboniferous sediments were deposited over an erosional unconformity on Caledonian basement, and, in western parts of the trough, on Devonian rocks preserved within the
Samarinbreen Syncline (Dallmann 1992).
Billefjorden Group strata occur both in the Inner Hornsund Trough and in western parts of the Sørkapp-Hornsund High. The lower formation, the Adriabukta Formation
(Birkenmajer & Turnau 1962) is confined to the trough. The overlying Hornsundneset Formation (Siedlecki 1960) may have been deposited continuously across the Sørkapp-Hornsund High and the Inner Hornsund Trough. Thin remnants of the Sergeijevfjellet Formation have also been reported from the trough (Gjelberg 1984).
A problem related to the Adriabukta Formation is its postulated Tournaisian to Viséan age that totally depends on the correctness of palynomorph age determination of only two samples (Birkenmajer & Turnau 1962). This dating also has critical tectonic implications, as the local Adriabukta folding event thus cannot be correlated with the Svalbardian folding. The grouping of the Adriabukta Formation within the Billefjorden Group must remain tentative until further biostratigraphic results are obtained.
Gipsdalen Group strata are confined to the Inner Hornsund Trough and are exposed along a segment of the Cenozoic fold-and-thrust belt. They are subdivided into the lower Hyrnefjellet Formation and the upper Treskelodden Formation (Birkenmajer 1959, 1964); these probably extend from the Bashkirian to the Asselian or Sakmarian and thus overlap in time with the other subgroups of the Gipsdalen Group. These two formations constitute the Treskelen Subgroup.
The above formations have not been redefined since their first description, though some of them have been extended into the Bellsund area after regional mapping (Dallmann et al. 1993; Ohta & Dallmann 1994). Units previously defined in areas north of Hornsund ("Reinodden Formation", Orvin 1940; "Drevbreen beds", Nysæther 1977) are correlated with the Treskelodden Formation and these names are recommended to be dropped in favour of the established and well-described stratigraphic nomenclature system which was established in the Hornsund area.
Thin fossiliferous limestone horizons overlying the Treskelodden Formation may be correlatives of the Wordiekammen Formation and, on Kopernikusfjellet, the Gipshuken
Formation.
The Kapp Starostin Formation of the Tempelfjorden Group forms a few metres thin horizon in the Inner Hornsund Trough, probably wedging out against the Sørkapp-Hornsund High.
The Early Carboniferous predecessor to the St. Jonsfjorden Trough was situated in north-central Spitsbergen, to the west of the line Kongsfjorden-Nordfjorden, the approximate onlap area of trough sediments on the western side of the Nordfjorden Block (Fig. 1-05, Fig. 2-02). To the south, the
Early Carboniferous basin reached the Bellsund area (Steel & Worsley 1984).
The Billefjorden Group rests unconformably on folded and eroded Caledonian basement, though remains of Devonian sediments occur locally and may underlie the Carboniferous.
Billefjorden Group strata of this basin have been referred to the monotonous, sandstone-dominated Orustdalen Formation (Cutbill & Challinor 1965) and the overlying, more heterogeneous, clastic "Vegard Formation" (Dineley 1958). The latter should be changed into the complete name Vegardfjella Formation. The "Trygghamna Formation" (Dineley 1958), a local name from the northern coast of Isfjorden, is equivalent to the Orustdalen Formation.
It has not been established in the geological literature for the benefit of the name Orustdalen Formation. In spite of the priority rule, we recommend use of the much better
established name in order to avoid unnecessary confusion.
Bashkirian-Moscovian sedimentation was confined to a narrow trough to the southwest of the Nordfjorden High, now exposed mainly in the inner part of St. Jonsfjorden and on Brøggerhalvøya. The conglomerate facies of the trough sediments that occur on Brøggerhalvøya are assigned to the Brøggertinden Formation (Orvin 1934) of Bashkirian to ?Moscovian age. The shale-dominated Petrellskaret Formation
and the red sandstone-dominated Tårnkanten Formation (Dineley 1958) probably form, at least in part, the age equivalents of the Brøggertinden Formation in the St. Jonsfjorden area. The upper, transitional part of the trough sediments on Brøggerhalvøya, the Scheteligfjellet Formation (Gobbett 1963: Scheteligfjellet beds) of Moscovian age was previously defined as a member of the "Nordenskiöldbreen Formation" (Cutbill & Challinor 1965) and is here raised to
formation rank in accordance with similar strata in the Billefjorden Trough. Upper parts of the Tårnkanten Formation (Jutulslottet member) may be laterally equivalent to the
Scheteligfjellet Formation. The Tårnkanten and Scheteligfjellet formations conclude the trough sedimentation to the west of the Nordfjorden Block. Together with the underlying
Bashkirian and Moscovian clastic formations, they constitute the Charlesbreen Subgroup, defining the sedimentary fill of the St. Jonsfjorden Trough.
The platform deposits of the Dickson Land Subgroup (Wordiekammen and Gipshuken formations) and the Tempelfjorden Group (Kapp Starostin Formation) overlie the fill of the St. Jonsfjorden Trough (see section 2.5.7).
The Billefjorden Trough, situated to the east of the Nordfjorden High, trends in a north-south direction along Wijdefjorden, Austfjorden and Billefjorden, and subcrops below
younger cover strata in the inner Isfjorden area (Fig. 1-05, Fig. 2-02). It formed a syndepositional trough from the Famennian to the Moscovian (Steel & Worsley 1984). Viséan strata overlap the western trough margin (at least in the south) and the eastern margin. Sedimentation was largely confined to axial areas of the half-graben during the Bashkirian, but the eastern basin margin was progressively onlapped during the Moscovian.
On the Nordfjorden High, Carboniferous sediments were deposited on Devonian rocks, while the Devonian had been completely eroded in the trough, exposing Caledonian folded basement prior to the onset of Carboniferous sedimentation. Consequently, both the Nordfjorden High and the Billefjorden Trough are inverted structures, due to tectonic movements along the Billefjorden Fault Zone during the Latest Devonian Svalbardian tectonic phase. The eastern crest of the Nordfjorden High formed the uplifted footwall of the Billefjorden Fault Zone during the Carboniferous movements; this crestal area was the longest emergent, at least until the latest Moscovian.
The Billefjorden Group within the Billefjorden Trough comprises the Hørbyebreen Formation and the Mumien Formation (see section 2.3.1).
Bashkirian to Moscovian trough sediments of the Gipsdalen Group (Campbellryggen Subgroup) comprise the clastic redbeds of the Hultberget Formation (see section 2.2), the mixed clastic, carbonate and evaporitic Ebbadalen Formation (Cutbill & Challinor 1965) and Minkinfjellet Formation (Cutbill & Challinor 1965), the latter being excluded from the platform-type "Nordenskiöldbreen Formation" and raised to formation rank due to its association with the Billefjorden Trough (see section 2.3.2).
The platform deposits of the Dickson Land Subgroup (Wordiekammen and Gipshuken formations) and the Tempelfjorden Group (Kapp Starostin Formation) overlie both the Billefjorden Trough and the Nordfjorden High (see section 2.5.7).
On eastern Spitsbergen and Nordaustlandet, the Upper Palaeozoic succession is less investigated than in other areas and several correlations must remain highly tentative.
Billefjorden Group sediments are only reported from the Lomfjorden area and have been assigned to the redbeds of the "Svenbreen Formation" (Cutbill 1968; see section 2.2). Recent investigations might restrict this occurrence to the west of the Lomfjorden Fault (S.G. Bergh, pers. comm. 1994). No formation name should be applied to this occurrence until more stratigraphic work is done. Correlations with the Hultberget Formation (Billefjorden Trough), Malte Brunfjellet Formation or Hårbardbreen Formation (Nordaustlandet) may turn out to be possible.
Clastic redbed deposits assigned to the Gipsdalen Group are found in several isolated places on the Ny Friesland High in Olav V Land (Olaussen et al. 1986, unpubl. report,
Statoil; Miloslavskij et al. 1998). Due to the lack of reliable correlations, the independent name Malte Brunfjellet Formation is proposed here.
On Nordaustlandet, the probably Bashkirian and/or Moscovian clastic Hårbardbreen Formation (previous member of the Gipshuken Formation [Cutbill & Challinor 1965] and Nordenskiöldbreen Formation [Lauritzen 1981]) is proposed for formational rank on a level with the coeval clastic and transitional trough successions of Spitsbergen.
Occurrences of a similar redbed unit in the Hinlopenstretet/Lomfjorden area have been described by Cutbill (1968) and Skarpnes (1984, unpubl.). Farther documentation is needed to verify a possible correlation with the Malte Brunfjellet and/or Hårbardbreen Formation.
Because of the lack of sufficient knowledge of the depositional regimes in north-eastern Svalbard, no subgroups should be assigned to these clastic deposits of the Gipsdalen Group east of the Billefjorden Trough.
Overlying platform deposits of the Wordiekammen and Gipshuken formations (Dickson Land Subgroup of Gipsdalen Group) and the Kapp Starostin Formation (Tempelfjorden Group) are present over the whole area (Burov et al. 1965; Cutbill 1968; Lowell 1968; Lauritzen 1981; Keilen 1992).
By the latest Moscovian/earliest Kasimovian, most of Svalbard (apart from the Inner Hornsund Trough and Sørkapp-Hornsund High) formed a carbonate shelf with little differentiation between earlier troughs and intermediate platform areas. These deposits comprise the Wordiekammen Formation (Late Moscovian to Sakmarian; see section 2.3.2) and the Gipshuken Formation (Mid to Late Sakmarian, ?earliest
Artinskian; Cutbill & Challinor 1965). These shelf deposits are gathered in the Dickson Land Subgroup.
After an Artinskian hiatus, shelf sedimentation was dominated by the bioclastic limestones and siliceous to carbonate, spiculitic lithologies of the Tempelfjorden Group, the Kapp Starostin Formation (Cutbill & Challinor 1965). Tempelfjorden Group strata are thought to have been deposited across all of Svalbard except for the Sørkapp-Hornsund High.
Back on top