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Transcript
Force Sedimentology Stratigraphy Group Seminar – Geological evolution of Eastern Greenland: Implications for
Hydrocarbon Prospectivity on the Norwegian Continental Shelf.
14 - 15 March 2006 at NPD, Stavanger, Norway
Palaeozoic Core Workshop:
Shallow stratigraphic cores from the Norwegian Sea off Helgeland
 Upper Permian and Lower Triassic reservoir rocks
 Upper Permian hydrocarbon source rocks
 Upper Permian evaporites
Hermann M. Weiss1, Jan Einar Ringås2, Atle Mørk3
1
SINTEF Petroleumsforskning AS, 7465 Trondheim, Norway ([email protected])
Statoil Forskningssenter, 7005 Trondheim, Norway ([email protected]); formerly IKU/SINTEF Petroleumsforskning AS
3
SINTEF Petroleumsforskning AS, 7465 Trondheim and NTNU, 7491 Trondheim, Norway ([email protected])
2
Abstract
Stratigraphic drilling in the Norwegian Sea off the Helgeland coast penetrated a 750 m thick,
fully marine succession of Upper Permian to Lower Triassic sedimentary rocks which can be
compared with rocks exposed onshore in East Greenland. The succession consists of
sandstones, turbidites, shales and reworked sabkha sediments. Observations made on these
cores contributed to a new, Palaeozoic play model for the mid-Norwegian continental shelf.
Twelve 1-m sections typical of the individual units will be presented and discussed during the
workshop. Information on the characteristics of potential source-rocks (a Ravnefjeld Fm.
equivalent) and oil staining found in these cores will also be given.
The nearly seven kilometres of core material collected by IKU/SINTEF in 1982 – 1993 are
since 2000 in care of the Museum of Natural History and Archaeology (Vitenskapsmuseet) at
the Norwegian University of Science and Technology (NTNU) in Trondheim. The NTNU use
the material in education and own research, and make it accessible to external academic
researchers. SINTEF Petroleum Research continue using the material in their own research
and consultant work, and keep cores and results accessible to the oil industry.
Paleo-landscapes of East Greenland: Pathways and barriers for sediment transport.
Ebbe H. Hartz,
Niels Hovius,
PGP, Oslo
Cambridge University
Sediment transport is guided by the topography of the Earth’s surface. Understanding the
paleo-landscape therefore is the key to unraveling how, where and when sediment was
supplied to depositional basins. We have studied the paleo-landscape of East Greenland
which has supplied sediment to one of the deepest local depositional basins (the Jameson
Land basin) during the Devonian to Cretaceous, and as well as the North Atlantic continental
shelf. In this study, we have reached beyond the areas with thick sedimentary cover that have
been the subject of many previous investigations, and traced paleo-surfaces into adjacent
areas with thin or discontinuous cover. There we have found that present and past landscapes
share common surfaces. The nature of these surfaces appears to be controlled strongly by the
properties of the substrate. For example, in heterogeneous, folded gneisses, resistant rock
units constitute topographic highs. In Milne Land, we have found that highs in gneisses first
formed at sea level, due to wave cutting of a Jurassic skerry coast. Paleo-islands have been
preserved, complete with distinct fossil faunas and sedimentary deposits on the wave and lee
side. Where sediments or granites were transgressed, wave beveling was more planar, but
locally erosional channels formed. The field data are complemented with regional geologic
and topographic data, including new LIDAR data, and satellite imagery. Using these
resources, paleo-surfaces were traced up to a hundred km away from the sedimentary
successions in which they were first recognized. Some paleo-surfaces are not offset by the
faults that are supposed to control the Jameson Land basin. This brings into question the
supposed rift origin of the basin. Generally, the Devono-Carboniferous paleo-surfaces are
mountainous, whereas the Late Permian and Mesozoic surfaces appear regionally planar and
parallel with the exception of channels and faultscarps. The ca. 55 Ma pre-basalt surfaces
generally follow the Mesozoic surfaces, but they have more relief. The most distinct surface
is a mid Cenozoic sub-horizontal plane, which clearly cuts the older folded surfaces. There is
no sedimentary cover on this surface, but it is well documented in cooling ages.
Thermochronological data from rocks below older, presently uncovered paleosurfaces
indicate that they were once deeply buried, and that thick sedimentary deposits extended far
beyond their current limits.
Carboniferous–Permian evolution of the northern North Atlantic and analogies between
East Greenland and Norwegian basins
Lars Stemmerik, GEUS
The southern Norwegian Barents Sea – Svalbard –North Greenland area forms the central
portion of the east–west oriented northern Pangaean shelf during Carboniferous–Permian
time. Integration of onshore geological data and offshore mainly geophysical data has greatly
improved our understanding of the evolution of this part of the shelf during Late Palaeozoic
time. The depositional evolution of the entire province to a large extent reflects shifts in
climate due to the shelf’s northwards drift from approximately 20 N to approximately 45 N
palaeolatitude during the Carboniferous and Permian. As a consequence, the region moved
from the humid tropical zone in the early Carboniferous through the northern arid zone in the
mid-Carboniferous to early Permian, before entering more temperate conditions in the midPermian. This long-term latitudinal shift in position and climate clearly affected depositional
conditions and resulted in division of the Carboniferous–Permian succession into four clear
second order depositional sequences. These sequences reflect long, 15–30 Myr periods of
relatively stable depositional conditions separated, at the sequence boundaries by abrupt
changes, which can be linked to ongoing rifting of the area, changing oceanographic
conditions and the northward drift of the region.
Outcrops in eastern North Greenland form well-exposed analogies to the Barents Sea
succession, and the well-exposed Carboniferous–Permian succession in East Greenland
provides important information about Upper Palaeozoic facies development offshore midNorway.
A review of the Post-Valanginian basin evolution of East Greenland
Whitham, A.G., Kelly S.R.A. and Strogen D.P.
East Greenland north of 70°N preserves a record of Cretaceous sedimentation from the
Valanginian to the Campanian. Subsequent to a major reorganisation of fault blocks
during rifting in the Volgian-Valanginian a sea floor topography dominated by fault
blocks was created and was maintained by faulting until the Mid-Albian. This
topography was in filled after the Mid-Albian and a shelf break margin was created and
maintained until at least the Campanian. It is possible that there were periods of
extension in the Late Cretaceous, but the timing of these movements is poorly
constrained. However, it is notable that there was no eastwards progradation of facies
belts from the Cenomanian-Campanian.
Post-Valanginian sedimentation was dominated by the accumulation of fine sediments.
However, significant thicknesses of coarse clastics are recorded at several stratigraphic
levels. Sandstone deposition is recoded in fluvio-deltaic, tidally influenced shallow
marine and deep marine depositional environments. Coarse material was transferred to
basinal settings during periods of lowstand, which occurred during the Barremian, Late
Aptian, Coniacian, Turonian and Campanian. The primary control on the input of
coarse sediment are steps in the basin-bounding fault. This control was maintained
after the change in basin floor topography in the Mid-Albian. The cross-rift transfer of
sediment is most likely to have occurred after the establishment of a shelf break margin
from the Cenomanian onwards.
Petroleum Source Rocks in East Greenland – a Review
Jørgen A. Bojesen-Koefoed, Lars Stemmerik and Flemming G. Christiansen
Geological Survey of Denmark and Greenland (GEUS)
Øster Voldgade 10
DK-1350K Copenhagen
The Upper Palaeozoic – Mesozoic succession in central East Greenland is the most
important outcrop analog to understand the stratigraphy and hydrocarbon potential of
the offshore basins on the North-East Greenland shelf and other areas in the North
Atlantic, including the Norwegian and Barents shelves, and areas near the Faroe
Islands.
Onshore East and Northeast Greenland, organic-rich sediments with petroleum
source potential have been identified in several stratigraphic levels ranging in age
from the Middle Devonian to the Jurassic (Cretaceous). In East and Northeast
Greenland, post-Caledonian sediments are exposed from Jameson Land to the south
to Store Koldewey to the north. The exposed Devonian–Cretaceous sedimentary
succession has a composite thickness of more than 10 kilometres, and seismic data
indicate thicknesses in excess of 15 kilometres in the Jameson Land basin. The
thermal maturity of the sediments is highly variable, both due to different burial
history but also because of regional variations in Tertiary volcanic activity
This presentation summarises the present knowledge on stratigraphy, distribution,
quality and geochemical characteristics of eight stratigraphic intervals having
petroleum source potential in East and Northeast Greenland.
Basin development of the Danmarkshavn Basin and analogy to the onshore East Greenland basins
Niels. E. Hamann & Lars Stemmerik
DONG, Copenhagen and GEUS, Copenhagen
The East Greenland shelf can be subdivided into a series of tectonic elements, several of
which can be linked to plate tectonics features along the North Atlantic margin, thus
confirming the pattern known from the Norwegian shelf. Tectonic activity became
concentrated towards the centre of the North Atlantic rift system in successive phases,
and basin subsidence began to take a NE orientation along the developing continental
margin.
A major Upper Palaeozoic salt basin, the Danmarkshavn Basin, located in the northeastern part of the shelf, was initially controlled by a pre-existing tectonic framework
following a N–S trend in East Greenland and along a WNW alignment in North
Greenland. Mesozoic rifting reached maximum intensity in the latest Jurassic and
continued into the Cretaceous. Following the opening of the Atlantic Ocean in the Early
Eocene deposition took place on a subsiding continental margin in a period of post-rift
thermal subsidence. Passive margin subsidence was interrupted by at several distinct
phases of regional basin margin uplift and inversion, resulting from several different
controlling mechanisms.
No wells have yet been drilled on the East Greenland shelf, so no direct stratigraphic
correlation of the seismic has been possible; therefore the well-exposed and well-known
succession onshore East and eastern North Greenland has been used to calibrate the
seismic units.
Evolution of the Late Palaeozoic–Mesozoic rift basin of East Greenland with special
emphasis on the Jurassic and Lower Cretaceous syn-rift deposits and their relevance as
petroleum system analogues
Finn Surlyk
Geological Institute, Geocenter Copenhagen
University of Copenhagen
Øster Voldgade 10
DK-1350 Copenhagen K
Denmark
East Greenland offers one of the World’s finest field laboratories for the study of siliciclastic
rift and thermal contraction basins, their stratigraphy, development, sequence stratigraphy,
facies and reservoir properties. The rift basin was initiated in the Late Palaeozoic and the
main Mesozoic rift events took place in Early Triassic, Mid Jurassic – earliest Cretaceous (
with a Late Jurassic climax) and in Mid Cretaceous times.
During Late Triassic – Early Jurassic times a thermal contraction basin was formed following
earlier phases of rifting. The main reservoir analogues in this basin are:
The Rhaetian–Sinemurian Kap Stewart Group; lacustrine and fluvial – correlative to the Åre
and Statfjord.
The Pliensbachian–Lower Bajocian Neill Klinter Group; shallow marine tidally and storm
influence – correlative to the Tilje etc., excellent analogue for Heidrunn
In the Mid – Late Jurassic rift basin the main reservoir analogues are:
The Upper Bajocian – Callovian Pelion Formation; shallow sandy backstepping shelf –
correlative to Garn, Brent etc.
The Lower – Middle Oxfordian Olympen Formation; the first Jurassic deep-water
depositional system with coarse-grained density flow deposits; shelf-slope-basin.
The Upper Oxfordian – Volgian Hareelv Formation; probably the World’s finest example of a
sedimentary injectite complex – excellent for injectite-dominated fields in the Paleogene of
the North Sea and for injectites in general.
The Volgian Raukelv Formation; shows similarities to Troll –coarse-grained shelf margin
wedges, extensive high-angle clinoform bedded sheets.
The Volgian–Valanginian Wollaston Forland Group; excellent analogue for the Brae province
– proximal marine syn-rift halfgraben fill deposited in the halfgraben.
A range of coarse clastic deep-water sediments were deposited during a succession of MidCretaceous faulting and rifting events:
The Mid Albian Rold Bjerge Formation; a chaotic breccia – base of slope and basin
The Upper Turonian – Lower Coniacian Månedal Formation; resedimented conglomerates
and sandstones – base of slope and basin
The Lower–Middle Coniacian (?)Vega Sund Formation; sand-rich turbidite basin floor fan.
The three units together serve as excellent analogues for deep-water depositional systems and
stratigraphic evolution of the outer Vøring Basin.
The East Greenland rift basin offers the possibility for a wide range of activities of relevance
to the oil industry, including:
Study of sand body geometries and dimensions, lateral lithological changes in grain size,
sand-shale ratios, connectivity in heteroliths and injectites, sequence stratigraphy and
predictability, source rock quality, thickness, lateral extent and stratigraphic occurrence.
The region has a great potential for general field courses and excursion, focused field trips
and field studies, training in facies analysis and sequence stratigraphy, comparison of core
workshop and log measurements in the field
Geological Setting – East Greenland and Norway.
Perspective- Greenland in the context of exploration and production in Norway.
Harald Brekke, Christian Magnus, Tore Høy, Robert W. Williams
Norwegian Petroleum Directorate
Exploration in the deep water areas in the Norwegian Sea offshore Norway has, since its
beginning in 1995, been focussed on the Cretaceous and Palaeocene sequences of the
Vøring and Møre basins. Information from the recent years of deep-water exploration
drilling and seismic campaigns in the Norwegian Sea continental margin is used to
update models for the geological development and the prospectivity of the Norwegian
deep-water areas. This includes a better resolution of the tectonic history of the
Cretaceous and Tertiary periods, a better understanding of the Early Cretaceous
configuration of the Vøring and Møre Basins, and seismic evidence of a Neogene tectonic
phase also affecting the early oceanic crust.Towards the end of the Cretaceous the
tectonic activity increased and culminated in Mid-Palaeocene accompanied by basin
uplift and widespread erosion of basin highs. The Vøring- and Møre Basins were
established by the main rifting episode in the Late Jurassic to earliest Cretaceous and
the subsequent Early Cretaceous thermal subsidence. Starting in latest Turonian to
earliest Coniacian times, the Vøring Basin was subject to Late Cretaceous block
faulting, flank uplift and increased subsidence.The Møre Basin, situated to the south of
the Jan Mayen Lineament, show little evidence of this tectonic activity. Minor
discoveries were made in reservoir sands of the Lower and Upper Cretaceous in the
eastern flanks of the basins before the deep-water drilling campaign started. In the
basins themselves, no well have so far penetrated rocks below the Turonian. However,
sandy intervals have been confirmed in the Conaician, Santonian, Campanian and
Maastrichtian, as well as in the Lower Palaeocene.
A remarkable turbidite fan system, the Modgunn Fan, is mapped on a 3D survey along
the southwestern flank of the Modgunn Arch. The fan is interpreted as belonging to the
Tang Formation in Middle Palaeocene. Seismic amplitude interpretation of the
Modgunn Fan shows a system with two main feeder channels. Smaller channels are
visible inside the main channels. Excellent examples of smaller splays and overbank
sediments expelled from the main system can be demonstrated. The thickness of the
central part of the channel system is in the range of 120 m. Seismic mapping indicates
that two separate channels are amalgamated vertically in the main course of the channel
system. The fan pinches out to the east originally as downlap, but is today uplifted on the
Modgunn Arch. The sediment transport of the fan system is from South West to North
East.
Interpretation of a few 2D lines westwards from the Modgunn Fan shows that the turbidite fan and
channels are fed from a delta on the Møre Marginal High only 15 km from the main submarine fan.
The delta is developed with nice clinoforms and topsets and shows the delta front and the pinching
out of the delta into the marin basin. There is also indication of erosion and sliding at the uppermost
and youngest part of the delta front. The Clinoforms indicate a transport direction from West /
Southwest Provenance studies show that a major part of the Cretaceous western and central basin
fill is derived from East Greenland, whereas minor contributions from the Norwegian mainland are
seen in deposits along the eastern basin flanks. The distribution in time and space of these sand
deposits is complex and further exploration calls for improved sedimentological models. Biostratigraphic studies of the late Cretaceous and lower palaeocene re-sedimentation history of the
Vøring and Møre Basins reveals a period of un-roofing of the Cretaceous to Permian sequences in the
hinterland. The conspicuous absence of any Jurassic spores in the re-sedimentation record and the
enormous volumes of Cretaceous sediments present put clear constraints on models for the
hinterland palaeography and the Cretaceous plate tectonically related uplift history of the
surrounding areas, including Greenland, the Barents Sea Shelf and Fennoscandia, and hence the
distribution of possible reservoir sands. To date several gas discoveries and one oil discovery are
made within the deep basin areas. The hydrocarbons are probably generated from both Jurassic (gas)
and Cretaceous (oil) source rocks. Well data indicate possible source rock intervals in the both Lower
and Upper Cretaceous of the basins and their eastern flanks but a good quality source rock of
Cretaceous age is still to be confirmed. In-house analyses of the state of oxidation of Cretaceous
shales indicate local favourable environment for the development of Cretaceous source rock within
the basin setting. The NPD play models of the Cretaceous and Lower Palaeocene of the Vøring and
Møre Basins are updated according to the latest well information of the area.
Geological evolution of the sub-volcanic Cretaceous-Paleocene Nuussuaq Basin, West
Greenland - An analogue to other sub-volcanic North Atlantic Basins
Dam, Gregers1, Pedersen, Gunver K.2, Sønderholm, Martin 3
1 DONG E & P, Agern Alle 24–26, DK-2970 Hørsholm, Denmark
2 Geological Institute, University of Copenhagen, Øster Voldgade 10, DK-1350
Copenhagen K, Denmark
3 Geological Survey of Denmark and Greenland, Øster Voldgade 10, DK-1350
Copenhagen K, Denmark
Abstract
The Cretaceous–Paleocene Nuussuaq Basin is the only one of the Late Mesozoic Palaeogene rift basins along the margins of West Greenland that extends into the
onshore areas in West Greenland. It represents a unique outcrop analogue to the
offshore basins, not only in West Greenland, but also to other North Atlantic subvolcanic basins.
Two major tectonic episodes have been recognised in the Early Cretaceous (Albian) and
Late Cretacecous-Paleocene, respectively. The succession records syn-rift deposition in
Albian times, deposition during a period of Cenomanian – Early Campanian thermal
subsidence, onset of rifting in Early Campanian and its growth in Maastrichtian – Early
Paleocene. Tectonic activity culminated in the Early Paleocene with regional uplift,
igneous activity and rapid subsidence. The early (Albian) rift episode was characterised
by deposition of fluvial, deltaic and shallow marine deposits, with few evidences of
proximity to large-scale normal faults, whereas sedimentation during the later
(Campanian – Paleocene) episode reflects active faulting, associated with continued
extension, regional uplift and igneous activity. More than 2 km of basaltic lavas erupted
within one million years or less.
The exposed part of the succession comprises discrete basin-fill phases,
which are mainly related to tectonic events and can be divided into eight tectonostratigraphic sequences (TSS); the early rift episode includes two TSS’s and the late
episode six TSS’s.
The oldest sediments of TSS 1 represent a syn-rift phase of Late Albian age.
It is dominated by fan-delta, wave- and fluvial dominated, shallow marine and Gilberttype delta deposits of the Kome and Slibestensfjeldet and possibly the lower part of the
Atane Formation. Locally discrete angular unconformities are present. TSS 2 represents
a long period of thermal subsidence that spans the Cenomanian/Turonian –earliest
Campanian. It is initated by a major flooding surface succeeded by fluvio-deltaic
deposits (Atane Formation). The fluvio-deltaic deposits pass into fault-controlled slope
deposits (Itilli Formation) west of the the N–S trending Qunnilik–Kuugannguaq Fault
and on Svartenhuk Halvø.
In earliest Campanian time a new tectonic episode was intiated and deltaic
deposition gave way to catastrophic deposition in a footwall fan setting along N–S
trending normal faults. This syn-rift succession corresponds to TSS 3 (Aaffarsuaq
Member). In Late Maastrichtian-Early Paleocene time the stress system in the region
changed and extension took place along NW–SE trending faults. This change in stress
system may be related to the opening of Baffin Bay. Later the arrival of the North
Atlantic Mantle Plume initiated large-scale igneous activity and subsequent magmatic
underplating, which resulted in regional uplift and erosion in the Paleocene. In the latest
Maastrichtian –earliest Paleocene three major tectonic phases have been recognised
(corresponding to TSS 4-6), each associated with incision of valley systems and
submarine canyons. The latest Maastrichtian phase gave rise to incision and filling of
two major NW–SE trending submarine canyons (TSS 4; Kangilia Formation). The TSS
5 (Quikavsak Formation, Tupaasat and Nuuk Qiterleq Members) is of earliest Paleocene
age and was associated with major uplift of the basin and valley incision into early
Paleocene fault scars. This phase was characterised by catastrophic deposition. The TSS
6 (Quikavsak Formation; Paatuutkløften Member) was associated with renewed uplift,
and valleys were incised into the old valley system. Crossing the Kuugannguaq–Qunnilik
Fault the valleys pass into a major submarine canyon system. The sandy fill of this
canyon system is referred to as the Agatdalen Formation. This phase was followed by
very rapid subsidence and deposition of transgressive estuarine and shoreface
sandstones and culminated with the extrusion of picritic hyaloclastite breccias. This
sequence of events (TSS 4–6) has been related to the arrival of the North Atlantic mantle
plume.
Extrusion of the volcanic succession constitute TSS 7-8 and is related to
continental break-up. TSS 7 is dominated by extrusion of olivine-rich basalts and
picrites (Vaigat Formation) and later by more evolved, plagioclase-phyric basalts
(Maligât Formation). As the volcanic front moved towards east, large lakes were formed
between the volcanic front in the west, and the cratonic crystalline basement in east,
giving rise to syn-volcanic lacustrine deposits (Atanikerluk Formation). Magmatic
activity in the Nuussuaq Basin resumed with an Early Eocene episode of intrusion of
dyke swarms and extrusion of basalts and sparse comendite tuffs (TSS 8).
Stratigraphy and depositional evolution of the subvolcanic, Cretaceous–Paleogene Kangerlussuaq
Basin, southern East Greenland
Michael Larsen et al.
Geological Survey of Denmark and Greenland (GEUS)
Øster Voldgade 10, 1350 Copenhagen K, Denmark
Present address
DONG E&P
Agern Allé 24-26, 2970 Hørsholm, Denmark
E-mail: [email protected]
In order to minimise risk in frontier areas like the Faroe-Shetland, Møre and Vøring Basins field
analogues may be crucial. The deep offshore area thus provides new opportunities, but it is also a
high-risk area with poorly known plays and sedimentary successions in part covered by basalts.
The Kangerlussuaq Basin in southern East Greenland exposes an approximately 1 km thick
sedimentary succession below the Paleogene flood basalts. The sediments are of Late Barremian to
Early Eocene age and were deposited at the western margin of the seaway between Greenland and
the UK. The succession records a long history of basin evolution starting with marine transgression in
the latest Barremian, shallow marine deposition during the Cretaceous, rifting and deep marine
deposition in the latest Cretaceous to early Paleocene, rapid uplift and fluvial erosion in the Late
Paleocene and onset of volcanism in the latest Paleocene to Early Eocene.
Plate reconstructions of the North Atlantic region indicate the former proximity of Greenland to the
Faroe Islands region and the Kangerlussuaq Basin probably constitutes the most important field
analogue with regards to stratigraphy, major unconformities and basin evolution. Major
unconformities in the Santonian–Early Campanian, Late Maastrichtian–Early Paleocene and midPaleocene may thus indicate periods of possible sediment input from the west to the Faroe-Shetland
region. Studies of potential source rock units, sediment provenance and basin uplift may further
improve the understanding of volcanic basin of the North Atlantic and may eventually lower the risk
on existing plays or lead to development of new play types.
The Greenland analogues were studied as part of SINDRI: “Future Exploration Issues
Programme of the Faroese Continental Shelf” established by the Faroese Ministry of
Petroleum and financed by the partners of the Sindri Group.
Provenance and diagenesis in the Jurassic of the Norway-Greenland rift
D.P. Strogen1, A.C. Morton1 and A.G. Whitham1,
1
CASP, Department of Earth Sciences, University of Cambridge, West Building, 181a Huntingdon
Road, Cambridge, CB3 0DH, UK.
This talk will discuss the results and methodology of a major provenance study carried out in the
Norway-Greenland Rift. Over 900 Jurassic-Recent sandstone samples were analysed by conventional
heavy mineral analysis, with geochemical analysis of garnets and tourmalines being undertaken on a
subset of the samples. SHRIMP U-Pb dating of detrital zircon grains was undertaken on a few
selected samples, to help further constrain the different populations identified on the basis of the
conventional analytical work. A number of sand source areas can be distinguished on both the
Norwegian and Greenlandic sides of the rift and the varying influence of each of these sand types has
been investigated across the rift through time. This talk will focus on the results of the Jurassic part
of this study.
Diagenesis and thermal maturity are also major concerns in the Norway-Greenland rift due to the
presence of extensive Paleogene flood basalts and related intrusions. The diagenesis and thermal
maturity of a number of Jurassic sections from East Greenland will be discussed, with emphasis on the
effects of volcanism.
The Early-Mid Jurassic of Mid Norway and East Greenland. A comparison.
Torben Olsen, Allard W. Martinius, Jan Einar Ringås, Alf Ryseth, Bjørn Terje Oftedal, Ingine K.
Strømsøyen (Statoil), Juha Ahokas (UiO)
Starting 2002 Statoil geologists have each summer carried out fieldwork in East Greenland and in
particular, on Jameson land. Aim has been to collect data from excellent outcrop analogues to the
Haltenbanken oil and gas/condensate fields. Value is created through improved quality of reservoir
management, particularly stratigraphic correlation, seismic interpretation, heterogeneity
characterization and reservoir model building. Another important aspect is staff training. The
spectacular East Greenland outcrops are real eye-openers.
In the Lower Jurassic there is a striking similarity in geological development between the Jamenson
Land and Haltenbanken basins. For the Åre, Tilje, Tofte and Ile reservoirs age- and facies equivalent
sections have been studied in the Kap Stewart and Niell Klinter Groups. Just as regional and intrafield variations can be seen on Haltenbanken so are regional variations present on Jameson land.
The Middle Jurassic Garn Formation formed as a result of significant shoreline progradation mostly
during Bajocian times and consists of a sand-dominated, coarse-grained sheet with excellent
reservoir properties. Strong wave activity on the prograding shorefaces can be inferred from
sedimentary facies. However, the Garn shoreline may also have been affected by strong tidal
currents. The overall regression was locally punctuated by transgressions leading to vertical stacking
of successive prograding units. In Jameson land the Pelion Formation also represents a mostly wavedominated, strongly progradational unit of mid Jurassic age. However, the timing of the Garn and
Pelion was seemingly slightly out of phase with most of the Garn Formation deposited before Pelion
deposition started. After the initial progradation Pelion deposition continued as back-stepping and
aggradational units until the end of the Middle Jurassic. This pattern of deposition is more similar to
the depositional pattern seen in the Middle Jurassic of the Viking Graben.
Analogy studies in Greenland require strong commitment, careful preparation and significant
funding. As for the latter, several sources have been “tapped”. Research funds for building a geosimulator (“Greensim”), partly in cooperation with GEUS, for various exploration studies and for
supporting CASP. Licence funds for extensive fieldwork in cooperation with the University of Oslo.
Staff training funds for developing and running internal field courses with support from GEUS. The
insight from Greenland may well create immense value for the oil industry but only when applied in
the producing assets. That implies both bringing field and exploration geologist to Greenland as well
as “bringing” Greenland to Norway, i.e. using the geosimulator technology.