NGF Abstracts and Proceedings, no. 3, 2006
Triassic of Svalbard and the Barents Shelf
Atle Mørk1 & David Worsley2
1) SINTEF Petroleum Research, NO-7465 Trondheim, Norway. eMail: atle.mork@iku.sintef.no
2) Færgestadveien 11, 3475 Sætre, Norway. eMail: david.worsley@prw.no
Introduction
Svalbard has been a key area for the study of
Arctic Triassic successions for over a hundred years.
The impressive almost flat-lying shales and
sandstones of central Spitsbergen (Fig. 1) drew early
attention because of their rich fossil content, and the
folded rocks along the western coast showed the
spectacular interaction of competent sandstones with
intensely deformed shales (Fig. 2). The relatively
easy accessibility of these high latitude areas made
them an early target for exploration, and rich fossil
faunas of ammonoids, bivalves and vertebrates
(ichthyosaurids and amphibians) attracted many
palaeontologists and stratigraphers (see historic
review by Buchan et al. 1965).
Equivalents of the Triassic succession of
Svalbard are also found throughout the Barents
Shelf. The transgressive - regressive sequences of
Svalbard and the Barents Shelf can be compared
with those of the Sverdrup Basin and East Siberia,
focusing on the very good correlation of
transgressive beds which also correspond to stage
boundaries, indicating a global origin for these
sequences (Embry 1997, Egorov & Mørk 2000 and
Mørk & Smelror 2001, Embry & Mørk 2006), all
located at the northern margin of Pangea facing the
Panthalassa Ocean (Fig. 3).
The start of exploration for hydrocarbons in the
Barents Sea in the 1970s and the need for
background material from Svalbard resulted in ship
and helicopter supported expeditions which made it
possible to visit remote parts of the Svalbard
Figure 1 The Triassic succession of Milne Edwardsfjellet, central Spitsbergen. The foot of the mountain is
formed by the Vikinghøgda Formation. The black cliff forming unit is the Botneheia Formation, which is overlain by the shaly Tschermakfjellet Formation and sandstone rich De Geerdalen Formation.
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NGF Abstracts and Proceedings, no. 3, 2006
Figure 2 The Triassic succession of Mariaholmen and
Midterhukfjellet in Bellsund, western Spitsbergen. The
massive rocks to the right are Lower Triassic clastics
of the Vardebukta and Tvillingodden formations. The
small valleys and peaks and the coastline at
Mariaholmen reflect the repeated coarsening-upward
sequences. The black folded shales in the central part
of the mountain belong to the Middle Triassic
Bravaisberget Formation, while the sandstones
capping the peak and adjacent to the shale on the left
hand side represent the Somovbreen and Van
Keulenfjorden members overlain by the folded Kapp
Toscana Group (to the extreme left).
archipelago in single field seasons. Sedimentological
and facies studies from the mid-1970s onwards were
supported by the oil industry, mainly Statoil, and
Svalbard research groups were established in the
universities of Bergen and Oslo (see review in Steel
& Worsley 1984). Close relationships were
established with the Geological Survey of Canada,
enabling comparisons of the sedimentary
successions. Russian geologists have a long tradition
of work on Svalbard, and the development of
perestroika politics in the late 1980s made
cooperation possible.
The great lateral similarities of the Triassic and
Lower Jurassic succession throughout Spitsbergen
and further to Barentsøya and Edgeøya were noted
by Mørk & Worsley (1979), and a regional synthesis
of the depositional environments and stratigraphical
nomenclature was reviewed by Mørk et al. (1982).
At the same time Pchelina (1980, 1983) published
her partly chronostratigraphical driven
nomenclature. The present lithostratigraphical
scheme for Svalbard, emended by an international
committee (Mørk et al. 1999a) revises and integrates
these previous proposals and also includes the
Triassic sequences found throughout the subsurface
of the Barents Shelf. The main sedimentological
development and present lithostratigraphical
framework are illustrated in Figure 4.
Sassendalen Group
Mørk et al. (1982) regarded most of the thickness
variations in the Lower and Middle Triassic
Sassendalen Group (from more than 700 m in the
(western) outer Isfjord area to less than 200 m on
Edgeøya) to have been largely caused by differential
movements over north-south trending lineaments. A
smoothed basin fill model (Fig. 5) based on the same
data shows that the succession thins eastwards from
a depocentre around the mouth of Isfjorden
(Festningen), while highly condensed sections are
characteristic of the Sørkapp-Hornsund High.
Three formations define the group in western
Spitsbergen, each representing major coastal
progradations from the west following initial
transgression and deepening, with the development
of barrier bars and lagoons in the basal Vardebukta
Formation, shallow marine bars and storm beds in
the Tvillingodden Formation and deltaic lobes in the
uppermost Bravaisberget Formation. The
Vikinghøgda Formation (Mørk et al. 1999b) of
central and eastern Svalbard is equivalent to the two
lower formations on the west coast, while the
Botneheia Formation is a distal equivalent to the
Bravaisberget Formation. Organic rich sediments
characterise the Botneheia Formation and the lower
prodeltaic parts of the Bravaisberget Formation;
these organic-rich shales were studied for their
interesting hydrocarbon source potential on the
Barents Shelf (Mørk & Bjorøy 1984, Leith et al.
1992). The Botneheia Formation shows TOC values
up to 10 %, with a preponderance of marine
kerogens, especially in eastern Svalbard. The
presence of oil and bitumen in the cracks of
septarian concretions led to the early name “Oil
Figure 3 The Pangea supercontinent in early Triassic
Time. Note that all Boreal areas from the Canadian
Arctic to Svalbard, North Greenland, Barents Shelf
and Siberia face the Panthalassa ocean without any
direct contact to Tethys.
E = Evaporites, C = Coal. Reconstruction by Trond
Torsvik, Norwegian Geological Survey.
NGF Abstracts and Proceedings, no. 3, 2006
Figure 4 Triassic stratigraphy and sequence development on Svalbard (from Egorov & Mørk 2000).
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NGF Abstracts and Proceedings, no. 3, 2006
Shale” for this unit in eastern Svalbard; the shales
are however generally immature as regards
hydrocarbon generation in this area.
Bjørnøya is the southernmost island in the
Svalbard Archipelago and the Triassic succession
there was studied by Pchelina (1972) and Mørk et al.
(1990), both works noting the development of
repeated transgressive - regressive cycles. The
sedimentary and tectonic history of Bjørnøya on the
Stappen High has recently been summarised by
Worsley et al. (2001), and this area shows a clear
resemblance to other neighbouring positive
structural elements of the Barents Sea, such as the
Loppa High further to the southeast and the
Sørkapp-Hornsund High on Spitsbergen itself. All
display Triassic clastic sediments progressively
onlapping older basement and Upper Paleozoic
sequences.
Sedimentation did not start on the SørkappHornsund High (Worsley & Mørk 1978) until the
mid Induan (Nakrem & Mørk 1991) - a similar
situation to Bjørnøya. Polymict basal conglomerates
on Sørkapp Land directly overlie metamorphic
basement or Paleozoic rocks of different ages
(Birkenmajer 1977, Worsley & Mørk 1978,
Dallmann et al. 1993) and the overlying Lower
Triassic succession has a relatively condensed
aspect. The Loppa High shows an even more
extreme development, where the crest of the high
was not transgressed until the mid-Triassic (Worsley
et al. 1988). In the central parts of Barentsøya, and
probably in similar platform situations, the oldest
Triassic sediments are of mid-Olenekian age
(Pchelina 1977). The stepwise transgression seen in
these areas is restricted to these local highs and
platforms and both central Spitsbergen and
southwestern basins were probably sites of almost
continuous sedimentation from the late Permian to
early Triassic (Mørk et al. 1989). In the Barents Sea,
Permian to Triassic beds have been penetrated by
shallow cores on the Svalis Dome (Nilsson et al.
1996, Vigran et al. 1998) and on the Finnmark
Platform off the coast of northern Norway (Bugge et
al. 1995), where a lowermost Triassic section,
resting concordantly on the Permian , resembles the
Sassendalen Group sediments of Svalbard. Deep
wells drilled in the Hammerfest Basin show
continuous and up to 900 m thick sequences ranging
from the latest Permian, which have also been
assigned to the Sassendalen Group (Worsley et al.
1988). Lower to middle Triassic successions in wells
drilled to date indicate repeated coastal
progradations from the Baltic Shield and the newly
developed Urals to the southeast, but generally
without any major coarse clastic input.
Kapp Toscana Group
The Kapp Toscana Group includes sediments
apparently ranging in age from the Ladinian
Figure 5 Thickness variations through the Lower and
Middle Triassic Sassendalen Group on Spitsbergen,
Barentsøya and Edgeøya.
(southwestern Barents Shelf) or Carnian (Svalbard)
to the Bajocian/Bathonian, all with greater sandstone
content than underlying units. The group has a
composite thickness of up to 475 m on Svalbard,
thickening to over 1,000 m in southern shelf areas.
Two major subdivisions represent varying
sedimentational regimes. The Ladinian to lowermost
Norian Storfjorden Subgroup shows major deltaic
progradations from several provenance areas, with
high subsidence and depositional rates. The
overlying mid-Norian to Bathonian Wilhelmøya
(Svalbard Platform) and Realgrunnen (southwestern
shelf) subgroups represent coastal to shallow marine
regimes, with much lower rates of deposition.
Prodeltaic shales of the Ladinian Tschermakfjellet Formation and deltaic deposits of the Carnian
to lower Norian De Geerdalen Formation thicken
eastwards and northeastwards over the archipelago
(Fig. 6), in contrast to the western depocentre
indicated by underlying units (Lock et al. 1978,
Mørk et al. 1982). Most localities – especially in
western and central Spitsbergen – demonstrate the
dominance of shallow marine reworking and
redistribution of deltaically introduced sediments.
Deltaic incursions from the west decreased through
the Carnian, while progradation from northeastern
NGF Abstracts and Proceedings, no. 3, 2006
Figure 6 The black cliff is the Middle Triassic
Botneheia Formation, overlain by the reddish
prodelta shales of Tschermakfjellet Formation
(Carnian). The thick sandstones represent the deltaic
facies of the De Geerdalen Formation (Carnian)
overlain by delta plain deposits. Edgeøya, eastern
Svalbard.
provenance areas provided a new dramatic influx of
texturally and mineralogically immature sands.
Preliminary data from the northern Barents Sea east
of Hopen show an extensive deltaic succession in
this area. Subsurface sequences in southwestern
shelf areas are also dominated by coastal
progradations: provenance from mature shield areas
resulted in markedly more mature sandstone
lithologies however.
In the Norian a transgression resulted in a
dramatic change in depositional regimes throughout
the region. Western and central Spitsbergen were
now a largely emergent platform, only transgressed
at times of maximum highstand, with preserved
exposures showing only a few metre thick
condensed and fragmentary sequence. The
Billefjorden Lineament was reactivated and eastern
areas show a thicker (<200 m) and somewhat more
complete latest Triassic to mid-Jurassic succession.
Southwestern shelf areas, especially the Hammerfest
Basin, show a mineralogically mature sandstonedominated sequence ranging in age from the Norian
to Bajocian and < 500 m thick.
Triassic Arctic Sequences
The general similarities of the different Arctic
Mesozoic successions have previously been noted in
detailed stratigraphical and palaeontological studies
by many workers. The transgressive - regressive
cycle patterns of Svalbard, the Barents Shelf and the
Sverdrup Basin (Embry 1988, Mørk et al. 1989)
clearly parallel each other (Fig. 5), as do those of
Svalbard, the Barents Shelf and eastern regions
(Mørk et al. 1992) and such cycles have now been
correlated throughout the Arctic (Egorov & Mørk
2000, Fig. 7).
Franz Josef Land represents the northernmost
Triassic exposures on the Barents Shelf and displays
an almost 5,000 m thick Triassic succession. Only
the uppermost 800 metres are exposed, while the
lower parts have been penetrated by three wells,
which show important differences through the
archipelago. The whole Triassic succession,
however, seems to form one major megasequence
(Preobrazhenskaya et al. 1985, Solheim et al. 1998)
composed of subcycles mainly corresponding to
stages and substages, arranged in coarsening upward
patterns indicating a similar cyclicity as described
for Svalbard and the Sverdrup Basin. Only coarse
clastics of Early Triassic age have been reported
from Novaya Zemlya, but on Kolguyev Island a
thick succession (<1317 m represented by four
formations) continues from the Timan-Pechora
Basin. Lower and Middle Triassic clastics also
continue offshore further into the southeastern
Barents Shelf, where a more than 1,500 metre thick
development has been reported. The Lower Triassic
there comprises multicoloured, red and grey finegrained clastics with sandstone interbeds decreasing
in abundance into the Middle Triassic. In the upper
Triassic, grey mixed clastics are similar to those
extending over large parts of the Barents Shelf and
represent coastal-marine depositional environments,
with increasing local marine influence upwards.
A circum-Arctic comparison and evaluation of
Triassic transgressive-regressive sequences was
presented to the Subcommission on Triassic
Stratigraphy at a symposium in 1991 (Mørk 1994).
This reflected data gathered on a field excursion in
East Siberia, which enabled Siberia to be
incorporated into the Svalbard - Sverdrup Basin
framework (Fig. 7). The fact that these circumArctic transgressions all started very early in a stage,
as dated by the fossil acmes in the transgressive
systems tracts, was further extrapolated to imply that
these transgressions had a much wider geographic
extension than the boreal areas of the AmEurAsian
plate (Mørk 1994, Embry 1997, Embry 2006, Embry
& Mørk 2006).
The International Subcommission on Triassic
Stratigraphy defined as one of their aims ‘to promote
research in order to clarify whether there are four
or five 2nd -order sequences recognisable in the
Triassic’ (Gaetani 1996). The indication of a fixed
number of high order sequences throughout the
Boreal Triassic that can be further recognised worldwide implies a common control on the formation of
these sequences, a suggestion leading to the idea of
global tectonics as the driving force (Embry 2006,
Embry & Mørk 2006).
There is a high correspondence of the Triassic
sequence boundaries throughout the Arctic, Jurassic
sequence boundaries also show a fairly good
correlation c.f. Smelror (1994), while the correlation
of Cretaceous sequence boundaries is poor (Mørk &
Smelror 2001). This indicates major global control
of the development of the Triassic sequences while
variations in age and development of the Jurassic
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NGF Abstracts and Proceedings, no. 3, 2006
Figure 7 Correlation of Triassic cycles between different Arctic areas (from Egorov & Mørk 2000).
and Cretaceous sequence boundaries indicate
progressively greater effects of local to regional
tectonic processes, possibly as a response to the
break-up of the Pangea Supercontinent, followed by
the development of the present-day Polar Basin.
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Nakrem, H.A., Vigran, J.O. & Weitschat, W. 1999: The type
section of Vikinghøgda Formation: a new Lower Triassic unit
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The Festningen section
Atle Mørk1 & David Worsley2
1) SINTEF Petroleum Research, NO-7465 Trondheim, Norway. eMail: atle.mork@iku.sintef.no
2) Færgestadveien 11, 3475 Sætre, Norway. eMail: david.worsley@prw.no
The section is named after Festningen ("The
Fortress"), a small islet with a lighthouse marking
the western approaches to Grønfjorden. The islet is
formed by almost vertical indurated Festningen
sandstone beds of Cretaceous age (Barremian) that
consist of fluviodeltaic deposits, some with large
dinosaur footprints.
An 8 km long coastal section from the
Precambrian to Cenozoic can be studied along the
southern coast of Isfjorden to the east of and around
Festningen itself (Fig. 1). The outcrops are within
the western fold-belt of Spitsbergen, resulting in
steeply dipping to vertical beds. The folding took
place during transpressive movements between
Greenland and Svalbard in the Eocene prior to the
Oligocene opening of this sector of the NorwegianGreenland Sea. The compressive tectonics involved
intense deformation of the shales in the succession,
so that significant overthrusting and shortening
affected these units. Metamorphic basement forms
the westernmost part of the exposures and Lower
Carboniferous braided stream conglomerates occur
lowermost in the post Caledonian succession.
However a gravel filled bay covers most of the
Carboniferous to Lower Permian succession; only
scattered exposures of carbonates and some remains
of collapse breccias representing upper
Carboniferous to lowermost Permian evaporites and
carbonates occur at the next point; these units are
beautifully exposed on the northern coasts of
Isfjorden. The Kapp Starostin Formation of Late
Permian age is a limestone – chert dominated unit
and its lower parts form the next major point. Kapp
Starostin itself takes its name from the Pomor
Russian Ivan Starostin who spent many of his
altogether 39 overwinterings in this area, before
being buried nearby in 1826. From base of this unit
it is possible to walk five km along well-exposed
coastal cliffs (Fig. 2). Harsh autumn storms with
rough waves wash the section clean, and in this way
we get new, clean exposures every year.
The Festningen section has been a standard
reference for Svalbard’s geology since early in the
last century, and Norwegian expeditions started
detailed studies here in 1908. The section was
logged in detail and extensive fossil collections were
made. These were described in a series of papers
during the following 30 years and the results of this
work were summarized by Hoel & Orvin (1937).
The area was then somewhat neglected for the
following 40 years and sporadic investigations were
restricted to partial redefinition of parts of the
succession in terms of the lithostratigraphical units
introduced in the1960s throughout Svalbard. In late
1970s studies by the universities of Oslo and Bergen
resulted in greatly improved understanding of the
depositional environments represented in the
succession (Steel & Worsley 1984). More recently a
revised lithostratigraphic scheme for the Mesozoic
of Svalbard and the Barents Sea also included a
revision of the Festningen succession (Mørk et al.
1999). Details from the Festningen Section will be
presented in a separate guidebook (Mørk & Worsley
2006).
The 400 m thick Kungurian to Upper Permian
Kapp Starostin Formation has bioclastic limestone
banks with brachiopods and bryozoans at its base.
These limestones grade up into shales with deeper
and colder water faunas, including prolific siliceous
sponges and bryozoans; spectacular zoophycoid
burrows are also common. The high (<70 %) content
of sponge spicules in the shales that dominate this
unit have produced the distinctive appearance and
texture of the resultant “spiculites”. These present
formidable operational problems – both to walk over
and drill through!
These spiculites alternate with sandy silicified
limestones in a series of three transgressive
regressive sequences in this type section; note that
the formation thins dramatically to only a few metres
of sandy limestones over regional highs.
The Triassic succession of the Festningen section
is represented by five formations, each starting with
a major sequence boundary; lower two of these have
their type sections along this coast. The shaledominated lower to mid-Triassic Sassendalen Group
is around 700 m thick here.
The 290 m thick basal (Induan) Vardebukta
Formation (type section here) is named after the
cairn on the coastal cliff within the bay (Vardebukta
= Cairn Bay). The aftermath of the late Permian
mass extinction can be seen as fossils are sparse in
the uppermost Permian spiculitic shales and virtually
absent in the lower 100 metres of the soft
Vardebukta Fm claystones. Even trace fossils are
quite sparse here. The latter are intruded by a
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NGF Abstracts and Proceedings, no. 3, 2006
Figure 1. Geological map of Svalbard with the Festningen Section enlarged in the lower part.
NGF Abstracts and Proceedings, no. 3, 2006
Figure 2. Schematic interpretative section through the sediments from the Late Permian to the base Cenozoic.
Thickness values are approximate as strong compression may have taken place in the shaly units.
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34
NGF Abstracts and Proceedings, no. 3, 2006
diabase sill, probably emplaced in the late Jurassic/
early Cretaceous. Deep shelf shales with occasional
storm siltstones low in the formation grade upwards
into massive sandstones and fossiliferous (Myalina
bivalves) beds with conspicuous Skolithos in the
shallowest coastal bar. Above this bar complex
deepening again occurs, with more shales and
siltstones in the upper part of the formation.
The 220 m thick Olenekian Tvillingodden
Formation (“Twin Point”, type section here) also
represents a major coarsening upward succession.
Parallel-laminated beds with sparse fossils and little
bioturbation grade up into shallow shelf
interlaminated shales and siltstones. Occasional
lenticular carbonate concretions may contain wellpreserved ammonoids. Interesting assemblages of
Rhizocorallium jenense in the upper part of the unit
indicate improved living conditions (Worsley &
Mørk 2001). A topmost bed contains mixed Spathian
and Anisian brachiopods and bivalves and represents
the basal Anisian transgression.
The Bravaisberget Formation (Anisian-Ladinian,
type section at the next fjord to the south) here
consists of dark shales at its base with thick
calcareous siltstone beds. Poorly preserved
ammonoids are abundant. Phosphatic nodules,
occurring as Thalassinoides tunnel fillings and as
nodular horizons (often at the bases of massive
siltstone beds) occur repeatedly through the lower
part of the formation. Extensive folding has taken
place in the dark organic rich shales, making
thickness estimates impossible, a rough estimate
being around 200 m. Towards the top of the
formation thinly laminated beds with abundant
phosphatic oolites and microcoquinal shell
fragments form a few metre thick unit. The
microcoquina beds are thought to represent the
remains of mass-deaths of juvenile bivalves. The
interplay of highly burrowed siltstone beds, galleries
of Thalassinoides tunnels, organic rich mudstone
and these microcoquinas indicate fluctuating oxygen
levels during deposition. The upper part of the
formation forms the Van Keulenfjorden Member
(“Fossesandstein” of early workers) representing
shallow, delta top silt- and sandstones deposited
above wave base.
A major transgression led to changing
sedimentational regimes at the advent of the late
Triassic. Over most of Svalbard a prodeltaic shale
unit, the Tschermakfjellet Formation, consisting of
grey (organic-lean) shales with red weathering
siderite nodules, marks the base of the Kapp
Toscana Group – here about 300 m thick. The
Tschermakfjellet Fm is almost absent at Festningen,
and is only represented by a few metres of shale
below the De Geerdalen Formation, which has
repeatedly small coarsening upwards rhythms from
shales to thin sandstone beds interpreted as sand
banks and shoals deposited in a moderately deep to
shallow shelf. Elsewhere this unit is characterized by
thick delta front and delta plain sandstones. The
uppermost 70 m of the formation show greenish and
red mudstones indicate restricted (?lagoonal)
depositional environments and these are included in
the Isfjorden Member. Similar beds are widespread
throughout the Barents Shelf and are of early Norian
age.
A thin polymict conglomerate containing pebbles
of quartz and phosphate forms the transgressive
Slottet Bed of the Wilhelmøya Subgroup. This
subgroup, here represented by the 18 m thick highly
condensed beds of the Knorringfjellet Formation,
thickens dramatically towards the East and South,
where it contains several sandstone-dominated
formations (the main hydrocarbon reservoir units of
the southern Barents Sea). The Triassic – Jurassic
boundary occurs within this unit, which at its top
contains a widespread polymict phosphate nodule
containing bed, the Brentskardhaugen Bed or “Lias
conglomerate”, with remanié fossils of Toarcian to ?
Bajocian age. This bed was not recognized in the
Festningen section by early workers but in 1978 we
dug it out of the scree in the creek following this
geological boundary.
Callovian marine sandstones overlie the
conglomerate and initiate a highly tectonised
approximately 400 m thick black shale unit, the
Janusfjellet Subgroup. Its Jurassic part, the
Agardhfjellet Formation, contains abundant organicrich paper shales, which are elsewhere (also in the
subsurface of the western Barents Sea) an excellent
source rock for hydrocarbons. Separated by an
unconformity the lowermost Cretaceous Rurikfjellet
Formation is also organic-rich, but without oil-prone
kerogen. This forms a coarsening upward and
shallowing succession, in its upper part loaded with
characteristic cannon-ball concretions.
Fluvial sandstones of the Festningen sandstone
itself follow with a marked erosional contact. Here
three thick distributary channels are preserved as
near-vertical beds, the lowermost of which has
revealed dinosaur footprints of an ornithopod
herbivore, previously referred to Iguanadon.
These beds belong to the 75 m thick fluviodeltaic
Barremian Helvetiafjellet Formation, whose upper
parts show a gradual transgression to the shallow
marine sandstones lowermost in the Aptian to
Albian Carolinefjellet Formation. This 320 m thick
unit (thinning to 100 m in Longyearbyen) shows
increasing clay content and deeper storm-generated
silt- and sandstones upwards. The occurrence of
Glendolites indicates significantly cooling water
conditions. Only the two lower members of this
formation were deposited and/or preserved here,
while further south- and eastwards the unit thickens
considerably to over 1,000 m in southern
Spitsbergen.
A pronounced hiatus separates these Lower
Cretaceous shales from the basal conglomerate of
the Cenozoic succession. Here a 40 – 50 Ma
NGF Abstracts and Proceedings, no. 3, 2006
duration hiatus demonstrates the regional upheaval
of the area during the late Cretaceous. A few metres
above the conglomerate, coals have been dug out in
a test mine; these belong to the same coal seam
mined in Barentsburg on the opposite side of the
fjord. Here only a small faulted outliner of this unit
is present and the remaining part of the succession is
scree-covered, before passing back down again into
the Carolinefjellet Formation just a little further
south along the coast of Grønfjorden. This completes
our 8 km long wander through about 220 Ma of the
earth’s boreal history!
References
Hoel, A. & Orvin, A.K. 1937. Das Festungsprofil auf Spitzbergen.
Karbon-Kreide. I: Vermessungsresultate. Skrifter om
Svalbard og Ishavet 18, 1-59.
Mørk, A., Dallmann, W.K, Dypvik, H.,Johannessen, E.P.,
Larssen, G.B., Nagy, J., Nøttvedt, A., Olaussen, S., Pchelina,
T.M. & Worsley, D. 1999. Mesozoic lithostratigraphy. In:
Dallmann, W.K. (ed.), Lithostratigraphic lexicon of Svalbard.
Review and recommendations for nomenclature use. Upper
Palaeozoic to Quaternary bedrock. 127—214. Norsk Polarinstitutt, Tromsø.
Mørk, A. & Worsley, D. 2006. Triassic of Svalbard and the
Barents Shelf. In: Nakrem, H.A. & Mørk, A. (eds.) Boreal
Triassic 2006. NGF, Abstracts and Proceedings of the
Geological Society of Norway, 3, 2006, (this volume).
Steel, R.J. & Worsley, D. 1984. Svalbard’s post-Caledonian
strata. An atlas of sedimentational patterns and palaeogeographic evolution. In: Spencer, A.M. et al. (eds.),
Petroleum Geology of the North European Margin.
Norwegian Petroleum Society, Graham & Trotman Ltd., 109135.
Worsley, D. & Mørk, A. 2001, The environmental significance of
the trace fossil Rhizocorallium jenense in the Lower Triassic
of western Spitsbergen. Polar Research 20, 37-48.
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