Force poster abstracts_20.11.13

Biostratigraphy, Geochemistry and Paleoenvironment of
Brucebyen Beds,basal Tyrellfjellet Member, Svalbard
Felix Gradstein1, Vladimir Davydov2, Carl Dons3, Jon Halvard Pedersen3 & Judith Hannah4
1
University of Oslo, Norway
University of Boise, ID, USA
3
Lundin Norway As
4
Colorado State U., Colorado, USA
2
Three Svalbard limestone localities were sampled for biostratigraphy, paleoenvironment and
organic maturation of the Brucebyen Beds, a potential Barents Sea petroleum source rock.
At both the Kapitol and Tyrellfjellet localities on Svalbard the Brucebyen Beds belong in the
Schwagerina robusta-Ultradaixina bosbytauensis fusulinid zone of latest Gzhelian age, latest
Carboniferous and 300- 298.9 Ma
In both localities samples with the fusulinid microfossils appear to be in place, and there is no
indication of abraded or fragmented specimens due to re-sedimentation. At the same time,
the microfossil specimens are severely compressed during early diagenesis, as many
specimens have post mortality damage or are crushed and broken. It appears that this
shallow-water limestone was very porous and permeable during sedimentation and early
diagenesis, allowing organics to easily migrate in the sample space.
A shale sample from Kapitol is oil and gas prone, and of low thermal maturity (TOC of 5.6%,
HI of 292 mgHC/g TOC and Tmax 434 C0). Gas chromatography analysis of a shale extract
suggest a marine, dys-oxic sedimentary environment (pristane/phytane 1.7). Vitrinite
reflectance of 0.6%Ro, calculated from aromatic compounds, indicates a maximum burial of
around 3.5 km (early oil window).
In the Kolosseum locality the bluish Brucebyen limestone belongs in the
Sphaeroschwagerina vulgaris –S. fusiformis fusulinid zone of earliest Asselian Age, earliest
Permian; 298.9 - 296 Ma. Samples are coarse, poorly sorted grainstone; some shells are
abraded and crushed before the diagenesis. The meteoritic cementation was very early.
Hence, organics had less possibility to migrate in than in the latest Gzehlian samples of the
other two localities.
Deposition of all samples was most likely initiated high in the photic zone in the warmest
waters above storm-weather wave base and possibly above fair-weather wave base. A global
warming trend at the Carboniferous-Permian boundary allowed migration of tropical fusulinids
northwards.
Managing biostratigraphic data with StrataBugs v2.0
John Athersuch, Paul Britton & Rosa Townsend
StrataData Ltd, 17 The Bothy, Ottershaw Park, Surrey UK – KT16 0QG, [email protected]
Since the time of William Smith, biostratigraphy has been a key technique for calibrating the
stratigraphic record. Advanced computational methods enable huge datasets, typically from
industry wellbore samples, to be systematically gathered, organised and manipulated.
StrataBugs is the industry-leading tool for the implementation of such procedures, allowing
users to probe the stratigraphic record at an ever finer resolution.
In StrataBugs, schemes and dictionaries, including a taxonomic database, stratigraphic
schemes and event composite standards, underpin all stratigraphic data. This encourages
consistency and standardisation throughout the database and enables events to be
correlated between stratigraphic sections.
Raw biostratigraphic data is easily entered using a variety of methods, including an
on-screen picklist or a touch-screen device. Microscope images can be referenced and
stored in the database.
Interpretation of well data is an iterative process which makes full use of the raw data and
supporting schemes. A set of preconfigured interactive charts gives a graphic snapshot of
the well or outcrop section. Data entry is facilitated by a ‘scheme picklist’, and many of the
data types can be edited directly from the charts – e.g. drag-and-drop interval boundaries. An
interactive graphic correlation tool facilitates definition of the age-depth profile (line of
correlation), including drag-and-drop nodes for its construction and refinement. Other charts
can display biostratigraphic data on age or TVD scales.
A typical workflow might be: enter the raw occurrence data, display the distribution chart and
pick events directly from it, use these well events together with an event composite standard
to define the age-depth profile. From this you can generate a preliminary list of biozones,
which can be viewed and refined using the chart, alongside other supporting data.
Foraminiferal assemblages from Lower Jurassic transgressive
mudstones of the southwestern Barents Sea
Silvia Hess1, Jenö Nagy1, Gitte Vestergaard Laursen2 & Bas van de Schootbrugge3
1
Department of Geosciences, University of Oslo, Norway;
2
Statoil ASA, Stavanger, Norway
3
Department of Geosciences, University of Frankfurt, Germany
Lower Jurassic sediments of the southwestern Barents Sea compose the Kapp Toscana
Group composed of sandstones, mudstones and shales deposited in shallow shelf to coastal
plain environments. Intervals of the Nordmela and Stø formations were sampled from cores
of two commercial wells (7119/12-1 and 7119/12-2) drilled in the Hammerfest Basin
(south-western Barents Sea). Foraminiferal assemblages were analyzed and integrated with
sedimentological data to assess depositional conditions, transgressive-regressive
developments and stratigraphic relations of the delta-influenced, marginal marine succession
forming the upper part of the paralic Kapp Toscana Group.
Foraminiferal assemblages occurred exclusively in transgressive mudstone intervals of the
Stø Formation in well 7119/12-1. High-energy marginal marine and offshore sandstones, and
freshwater deposits were barren of foraminifera. All foraminiferal assemblages contain only
agglutinated taxa with high dominance of Ammodiscus and Trochammina. Species diversity
is extremely low (Fisher α < 5). These features and analogies to modern faunas indicate
restricted environmental conditions with low salinity as the main restricting factor in strongly
delta-influenced waters.
The three mudstone horizons of the Stø Formation represent marine transgressions. Their
foraminiferal content reveals Pliensbachian-Toarcian affinities. These transgressive
mudstones are considered as local developments of the global Pliensbachian-Toarcian
transgressions and associated major faunal changes. In addition to the age relationships
suggested by the foraminiferal assemblages, this consideration is based on the transgressive
nature of these mudstone horizons, their slightly increased TOC content and a negative
δ13C-isotope excursion which is characteristic for the Toarcian Oceanic Anoxic Event.
Our results show that foraminiferal assemblages can be used to recognize
paleoenvironmental changes in paralic environments. They clearly indicate regional
transgressive events in shallow water deposits which could serve as key horizons for
basin-wide correlation. Planed foraminiferal analyses combined with detailed carbon isotope
data can contribute significantly to delineate the stratigraphy of this, until now, poorly dated
succession.
Interactive Biostratigraphy of the North Sea
Rebecca Bobick1, Felix Gradstein2, James Ogg1 & Dirk Munsterman3
1
Purdue University, Indiana, USA
2
University of Oslo, Norway
3
NO, Utrecht, The Netherlands
We have produced an extensive and user-friendly stratigraphy dataset for the North Sea
ranging from Triassic through Cenozoic using Time Scale Creator; a visualization program
that allows users to interactively view all types of Earth history data. The North Sea fossil
suites consist of dinoflagellate cysts, pollen-spores and foraminifers. All data was scaled to
the standard international geologic time scale 2012. The information for each individual fossil
range, biozone and regional lithologic facies is readily accessible. The 2000+ data points also
include over 300 images of the fossils that appear on the user-generated and selected charts
for quick identification and larger versions within mouseover popup windows in the on-line
version of the user selected charts. The pop-ups also contain external links to more
information for the fossils (e.g. the Dinoflaj compilation and Grzybowski Foundation
taxonomy) and time calibration information from international GTS2012. The Time Scale
Creator visualization system itself has options for user customization, such as selecting the
time intervals, vertical scale and specific fossil of geochem or geomagnetic columns to view.
By allowing easy accessibility and providing a user-friendly interface and specific columns to
view this program may aid in education, consolidation of research products and offshore
biostratigraphy in the North Sea.
Stratigraphic Guide to the Rogaland Group,Norwegian North Sea
Harald Brunstad1, Felix Gradstein2,Jan Erik Lie1, Øyvind Hammer2,
Dirk Munsterman3, Gabi Ogg4 & Michelle Hollerbach5
1
Lundin Petroleum AS Norway, NO-1366 Lysaker, Norway.
Geology Museum, University of Oslo, NO-0318 Oslo, Norway.
3
TNO, P.O. Box 80015, NL-3508 TA Utrecht, The Netherlands.
4
1224 N Salisbury St, West Lafayette, IN 47906, USA.
5
Senergy AS, Strandkaien 2, NO-4004 Stavanger, Norway.
2
This guide provides a major revision and update of the lithostratigraphy of the Rogaland
Group for the Norwegian North Sea. An abundance of recent well and seismic data sheds
new light on lithology, biostratigraphy, provenance, geographic distribution and terminology of
all Rogaland rock units, used widely in the search for oil and gas.
While finer siliciclastic units largely remain as previously defined, previous
sandstone/siltstone formations and one (reworked) chalky unit are now re-defined. These
lithostratigraphic units are local sediment bodies of a lithology different from the surrounding
and embracing formation. Hence, these lithostratigraphic units are members in the formal
stratigraphical hierarchy. With the new definitions and re-definitions the Rogaland Group now
consists of four formations and 15 members, which span the stratigraphic interval from lower
Paleocene to lower Eocene.
The revisions concerning the sandstone bodies are of four different types: Re-definition from
formations to members; re-definition of lithological criteria; introduction of members long used
already offshore England and Denmark; definition of new members.
For those practicing geologists not familiar with historic precedence, an important ‘sine qua
non’ in (litho-) stratigraphy, it should be pointed out that 8 out of 15 members discussed here
have been predefined in literature dealing with the UK and Danish sectors of the North Sea.
The present study thus updates the Norwegian lithostratigraphic bulletins of the nineteen
eighties for its offshore area. Each unit has a detailed biostratigraphy and age section also.
The internet site www.nhm2.uio.no/norlex provides an interactive digital version of this study,
with links to well data, biozonations and core archives.
Carnian palynology from a shallow stratigraphic core from the
Sentralbanken High, Barents Sea
Holen L. 1, Mangerud, G. 1, Paterson, N.W. 1, Lundschien, B.A. 2,
Throndsen, I. 3 & Miljeteig, K.I. 1
1
Department of Earth Science, University of Bergen, Allégaten 41, N-5007 Bergen, Norway, 2Norwegian
Petroleum Directorate, P.O. Box 600, 4003 Stavanger, Norway
3
Applied PetroleumTechnology AS (APTEC), P.O. Box 123, 2027 Kjeller, Norway
During the Triassic Period, a major embayment formed on the northern coast of the Pangea
Supercontinent in what is now the Barents Sea. During the Late Triassic this embayment
was gradually filled by sediment derived mainly from the erosion of the recently uplifted
Uralian Mountains. These sediments formed a huge prograding delta which gradually
converted into a paralic platform. Very little data are available from the Northern Barents
Sea; however, several stratigraphic cores drilled by the Norwegian Petroleum Directorate in
the area offer a unique insight into the Late Triassic stratigraphy and paleogeography of the
region.
The present study forms a master’s thesis in palynology of a shallow core, 7533/3-U-7, drilled
through the Snadd Formation from the Sentralbanken High in the Northern Barents Sea.
This study constitutes part of a broader palynostratigraphic investigation of the Middle to Late
Triassic of the Barents Sea currently being undertaken at the University of Bergen. From core
logging, the preliminary interpretation indicates a mid to upper delta plain depositional
environment.
The main aims of the thesis are to date the core and evaluate the paleoenvironments
represented by utilising palynological and palynofacies analyses. By combining
palynostratigraphic and palynofacies data it is hoped that any marine incursions will be
recognised and dated, thereby enhancing our current understanding of the Late Triassic
paleogeography of the Barents Sea. Together with documentation of the recorded
palynomorphs, a preliminary correlation to published sections on Svalbard and to the shallow
core 7830/3-U-1 drilled offshore Kong Karls Land will be presented.
Carnian palynology from a shallow stratigraphic core offshore
Kong Karls land, Barents Sea
Miljeteig, K.I. 1, Mangerud, G. 1, Paterson, N.W. 1, Lundschien, B.A. 2,
Throndsen, I. 3 & Holen L. 1
1
Department of Earth Science, University of Bergen, Allégaten 41, N-5007 Bergen, Norway, 2Norwegian
Petroleum Directorate, P.O. Box 600, 4003 Stavanger, Norway
3
Applied PetroleumTechnology AS (APTEC), P.O. Box 123, 2027 Kjeller, Norway
During the Triassic Period a major embayment formed on the northern coast of the Pangaea
Supercontinent in what is now the Barents Sea. During the Late Triassic this sea was
gradually filled by sediment derived mainly from the erosion of the recently uplifted Uralian
Mountains. These sediments formed a huge prograding delta which gradually converted into
a paralic platform. Very little data are available from the Northern Barents Sea; however,
several stratigraphic cores drilled by the Norwegian Petroleum Directorate in the area offer a
unique insight into the Late Triassic stratigraphy and paleogeography of the region.
The present study forms a master’s thesis in palynology of a shallow core, 7830/3-U-1, drilled
through the Snadd Formation, equivalent to the Tschermarkfjellet and De Geerdalen
Formations, from offshore Kong Karls Land in the Northern Barents Sea. This study
constitutes part of a broader palynostratigraphic investigation of the Middle to Late Triassic of
the Barents Sea currently being undertaken at the University of Bergen. From core logging,
the preliminary interpretation indicates a range from prodelta, to delta front and
interdistributary bay depositional environments.
The main aims of the thesis are to date the core and evaluate the paleoenvironments
represented by utilising palynological and palynofacies analyses. By combining
palynostratigraphic and palynofacies data it is hoped that any marine incursions will be
recognised and dated, thereby enhancing our current understanding of the Late Triassic
paleogeography of the Barents Sea. Together with documentation of the recorded
palynomorphs, a preliminary correlation to published sections on Svalbard and to the shallow
core 7533/3-U-7 drilled on the Sentralbanken High will be presented.
A new, formal palynozonation for the Triassic succession
of the Barents Sea area - a solid correlative tool for the
Norwegian Arctic
Mangerud, Gunn1, Jorunn Os Vigran2, Atle Mørk2,3 Peter A. Hochuli4 & David Worsley5
1
Department of Earth Science, University of Bergen, Allégaten 41, N-5007 Bergen, Norway, 2 Sintef Petroleum Research,
3
NO-7465 Trondheim, Norway, Department of Geology and Mineral Resources Engineering, NTNU, NO-7465
Trondheim, Norway 4Palaeontological Institute and Museum, University Zürich, Karl Schmid-Str. 4, CH-8006 Zurich,
5
Switzerland, Fergestadsveien 11, N-3475 Sætre, Norway.
The Norwegian Barents Shelf with Svalbard forming its exposed north-western corner reveals
an almost complete Triassic sedimentary record when combining outcrops with stratigraphic
cores and explorations wells. Dating and reliable correlation tools are essential in exploration,
and palynological studies from these sections have been carried out resulting in the definition
of fifteen palynological Composite Assemblage zones (CAz).
Calibrations with ammonoids recovered from Lower and Middle Triassic deposits cored on
the Svalis Dome, the Bjarmeland Platform, in Finnmark East and in the Nordkapp Basin
permit exact dating of the co-appearing palynological assemblages and confident correlation
with the ammonoid-dated sections on Svalbard.
Shallow cores from Sentralbanken and off Kong Karls Land add valuable knowledge of the
Late Triassic and the variable depositional environments and breaks in deposition during the
Carnian and Norian. Important data are added based on exploration wells.
At the Triassic-Jurassic transition on Svalbard, where Lower Jurassic deposits directly overlie
Norian beds, we demonstrate that reworked Late Triassic palynomorphs dominate. In
exploration wells further to the southeast, Rhaetian strata represent the youngest Triassic
deposits in the area.
Seven composite assemblage zones have been defined for the lower Triassic. These include
the Uvaesporites imperialis, Reduviasporonites chalastus, Proprisporites pocockii,
Maculatisporites spp., Naumovaspora striata, Pechorosporites disertus and Jerseyiaspora
punctispinosa CAz. These appear to have a variable west-east presence on Svalbard.
Four composite assemblage zones have been defined for the Middle Triassic. These include
the Anapiculatisporites spiniger, Triadispora obscura, Protodiploxypinus decus, and the
Echinitosporites iliacoides CAz and are present in most measured sections on Spitsbergen.
On Bjørnøya there is a major stratigraphic break above Smithian beds where the oldest
Middle Triassic is represented by the Ladinian E. iliacoides CAz.
Four Composite Assemblage zones have been defined for the Late Triassic. These include
the Aulisporites astigmosus, Rhaetogonyaulax spp., Limbosporites lundbladii and
Quadraeculina anellaformis CAz. However, in most localities on Svalbard only the Carnian A.
astigmosus CAz is recognised.
The present study represents a comprehensive compilation of palynology from the Triassic
succession of the Norwegian Arctic. There is still a huge potential for further detailed work of
the palynoassemblages and their application in palaeoenvironmental as well as stratigraphic
interpretations and reconstructions. The results will be presented in the book:
J. O. Vigran, G. Mangerud, A. Mørk, D. Worsley, P. A. Hochuli. 2013: Palynology and
geology of the Triassic succession of Svalbard and the Barents Sea. Norwegian
Geological Survey, Special Publication.
Integrated biostratigraphy and foraminiferal biofacies from a Late Cretaceous fan system
in the Vøring Basin
Eiichi Setoyama1*, Wiesława Radmacher2, Michael A. Kaminski1,3, Jarosław Tyszka2
1
Earth Sciences Department, King Fahd University of Petroleum & Minerals, Dhahran, 31261,
Saudi Arabia *E-mail: [email protected]
2
Polish Academy of Sciences, Institute of Geological Sciences, Cracow Research Centre,
BioGeoLab, ul. Senacka 1, 31-002, Kraków, Poland
3
Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT,
UK
Foraminifera and dinoflagellate cysts from the Upper Cretaceous on the Nyk High, the Vøring
Basin were analysed in order to document their biostratigraphic ranges and to analyse
foraminiferal biofacies of different fan sub-environments previously proposed based on
ichnofossils by Knaust (2009). The studied core samples from well 6707/10-1 includes the
Tumler Member of the Kvitonos Formation, the Spekkhogger Member of the Nise Formation
and the Hvithval Member of the Springer Formation.
The foraminiferal assemblages are composed exclusively of deep-water agglutinated taxa and
generally diversified. Foraminiferal species with biostratigraphic values were, however, not
recorded. The assemblages show some similarity to those described from the Fenestrella belli
Zone of Gradstein et al. (1999) in their completely agglutinated nature and the presence of
species of Gerochammina. The dinocyst assemblages are also diversified, and more reliable
dating of the studied interval was provided based on bioevents of dinocysts that can be
correlated to ones reported from the southwestern Barents Sea, the North Sea and Greenland.
Those include the last occurrences of Heterosphaeridium cf. difficile and Odontochitina spp and
the presence of pollen, Wodehouseia spinata. The whole interval is estimated to be of
Santonian–Maastrichtian age.
The relatively high diversity of foraminiferal assemblages with abundant tubular forms support
the middle–upper bathyal palaeobathymetric estimation previously made for the northwest
Vøring Basin by Gradstein et al. (1999). The comparison of assemblages from different
subenvironments of a fan system shows that the species diversity and relative abundance of
morphogroups are inconsistent due to small numbers of specimens in the inner to middle fan
assemblages. Deep infaunal forms may be more common in this subenvironment, but the
abundance is so low that this observation should be treated carefully. In contrast, the
abundance and diversity of the assemblages from the overbank, fringe and basin plain
subenvironments are relatively high, and their morphogroup composition is also comparable to
each other where the assemblage size is large. The presence of bottom water currents, possibly
in the form of a western boundary current, is suggested based on the abundant occurrence of
tubular forms in the overbank, fringe, and basin plain subenvironments.
References
Gradstein, F.M., Kaminski, M.A., Agterberg, F.P., 1999. Biostratigraphy and paleoceanography
of the Cretaceous seaway between Norway and Greenland. Earth Science Reviews 46, 27–98.
Knaust, D., 2009. Characterisation of a Campanian deep-sea fan system in the Norwegian Sea
by means of ichnofabrics. Marine and Petroleum Geology 26, 1199–1211.
Setoyama, E., Radmacher, W., Kaminski, M.A., Tyszka, J., 2013. Foraminiferal and
palynological biostratigraphy and biofacies from a Santonian–Campanian submarine fan
system in the Vøring Basin (offshore Norway). Marine and Petroleum Geology 43, 396–408.