The Research Centre for Arctic Petroleum Exploration is happy to present the program for the digital ARCEx Annual Conference, taking place online, 19-22 October, 2020.

The digital conference will be an event over four days, from 12h30 to 15h00 Monday to Thursday. This year we will focus on the research results presented by the ARCEx fellows. The topics for the four days are:

  • Mon. 19 Oct. – Technology for eco-safe exploration in the Arctic
  • Tue. 20 Oct. – Petroleum geosciences
  • Wed. 21 Oct. – Environmental risk management
  • Thu. 22 Oct. – Petroleum geosciences

To participate you must be associated with the ARCEx consortium (partner organisations are listed here). Participants outside the consortium are by invitation only.

Time: 19-22 October 2020, 12h30-15h00. Add to your calendar.
Place: Online – links will be sent to the registered participants a few days before the event.
Registration: Follow the link below to register.

Program

Please note that the program may be updated. Abstracts are now available – click on the presentation title to view the abstract or download a pdf here.

  • Monday 19 Oct 2020
  • Tuesday 20 Oct 2020
  • Wednesday 21 Oct 2020
  • Thursday 22 Oct 2020

Monday 19 Oct 2020

Technology for eco-safe exploration in the Arctic

Welcome to the conference!

Alfred Hanssen and Ellen Ingeborg Hætta, UiT, Tor Arne Johansen, UiB

Welcome! ARCEx Director Prof. Alfred Hanssen and Administrative Leader Ellen Ingeborg Hætta will give the participants an update on the status of ARCEx - Research Centre for Arctic Petroleum Exploration.

 

Host/moderator for the day: Tor Arne Johansen, TorArne.Johansen@uib.no

Technical facilitator: Ellen Ingeborg Hætta, ellen.i.hatta@uit.no, mobile: +47 988 01 001

Mon 12:30 - 12:50
Other

Potential use of seismic for Arctic climate monitoring.

Helene Meling Stemland, UiB

Potential use of seismic for Arctic climate monitoring.

Helene Meling Stemland1, Tor Arne Johansen1, 2, Bent Ole Ruud1

1Department of Earth Science, University of Bergen, Bergen, Norway
2The University Centre in Svalbard, Arctic Geology, Svalbard Science Centre, Longyearbyen, Norway

Arctic surface temperatures are currently increasing at the highest pace on earth, and an implication of this is thawing of currently frozen ground. The extent and timing of thawing is, however, uncertain, but is important to understand because thawing can have significant geomorphic consequences and cause release of greenhouse gases. To facilitate efficient and environmentally friendly monitoring of permafrost degradation, non-intrusive methods are desirable.

We have acquired both active and passive seismic data in Adventdalen on Svalbard during several field seasons and have observed temporal variation in the data that is likely due to seasonal thawing of the active layer. To investigate whether seismic can also be useful for detecting and monitoring longer-term degradation of permafrost due to climate change, we have conducted a modeling study where we combine heat flux, rock physics, and seismic modeling to estimate the change in seismic properties related to future climate scenarios as proposed by the Intergovernmental Panel on Climate Change (IPCC). The IPCC estimate global mean temperature increases of 0.3 – 4.8°C from the end of the 20th century to the end of the 21st century, but the Arctic regional mean temperature increase is expected to be approximately three times greater than the global mean.

For a simple sediment model constructed from well data from Adventdalen, we model heat flux conduction into the near-surface unconsolidated sediments for various surface temperatures. We make the assumption of saline pore water in the sediment model, which is common in coastal areas and affects the transition from ice to water and, hence, the stability of the sediments. We find that increased surface temperature causes increased thawing depth. By combining these results with rock physics modeling, we find that the elastic and seismic properties of the near-surface sediments vary significantly with time and depend strongly on the pore water chemistry. The results indicate that time-lapse analysis of seismic data may be useful for evaluating consequences of rising temperatures in the Arctic.

Reference:

Stemland, H.M, Johansen, T.A., Ruud, B.O., & Mavko, G., 2020. Elastic properties as indicators of heat flux into cold near-surface Arctic sediments, Geophysics 85(5), MR309-MR323.

Mon 12:50 - 13:10
WP4 Technology for Eco-Safe Exploration, Scientific presentation

Electromagnetics in the Barents Sea - A controlled case study based on the Wisting field.

Vemund Thorkildsen, UiO

Electromagnetics in the Barents Sea - A controlled case study based on the Wisting field.

Vemund Thorkildsen and Leiv J. Gelius
Department of Geosciences, University of Oslo, Oslo, Norway

The Wisting oil field was found in 2013 and contains an estimated 300-500 million barrels of oil equialents. The oil bearing formations are mainly Stø, Nordmela and Fruholmen, and the crest of the structure lies only 250 meters below the seabed. We have built a geological model constrained by stratigraphy (figure 1). This model will be populated with resistivity values from nearby wells and serve as a starting point for a sensitivity study. The electromagnetic response of such a controlled model can also be compared to field data acquired from the area. The controlled- and field response can then be inverted by employing an identical inversion grid, creating a closed loop as described by Granli et. al (2017).

Figure 1 - Stratigraphic model of Wisting.

The diffusive nature of the electromagnetic wave propagation implies that higher frequencies are rapidly attenuated. However, as the Wisting field lies only 250 meters below the seabed, higher frequencies might still be sensitive to the reservoir.  In our work, we investigate the resolving power of Controlled Source and Magnetotelluric EM for shallow reservoirs. The study includes a characterization of sensitivity as a function of frequency and offset in addition to the sensitivity related to a varying Oil-Water Contact. An inversion scheme should allow for some degree of freedom in the starting model without altering the end result significantly. Therefore, the robustness of the inversion will be investigated by varying the starting model in order to validate our inversion results.

Reference: 

Granli, J. R., Veire, H. H., Gabrielsen, P., & Morten, J. P. (2017). Maturing broadband 3D CSEM for improved reservoir property prediction in the Realgrunnen Group at Wisting, Barents Sea. In SEG Technical Program Expanded Abstracts 2017 (pp. 2205-2209). Society of Exploration Geophysicists.

Mon 13:10 - 13:30
WP4 Technology for Eco-Safe Exploration, Scientific presentation

Coffe break

The host and presenters will hang around and answer your questions directly via chat or video before we continue the session after the break.

Mon 13:30 - 13:45
Break

Estimating blue whale source level and vocalizing depth from single sensor observation.

Léa Bouffaut, NTNU

Estimating blue whale source level and vocalizing depth from single sensor observation.

Léa Bouffaut, Martin Landrø, John R. Potter
Department of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway

For many decades, passive acoustic monitoring has been proven to be an economical and non-intrusive way for conducting blue whale surveys at large spatial scales using their low-frequency vocalizations. An accurate estimation of the source level and source depth is crucial to ensure its success. Key to understanding and modeling acoustic propagation, these values are needed to assess the impact of anthropogenic noise on animal communication, masking effects, or even for animal density estimation. However, prior estimates of blue whale source levels in the Southern Ocean are sparse and date back to the early 2010s. Plus, vocalizing depths are unknown. This work focuses on the critically endangered Antarctic blue whale (Balaenoptera musculus intermedia) and the Madagascar pygmy blue whale (Balaenoptera musculus brevicauda - data deficient).

Multipath propagation recorded by a single bottom-hydrophone is exploited to estimate source levels and vocalizing depths. First, whale calls are automatically detected and the corresponding received levels are measured. The range is then estimated from the multipath timing in order to estimate transmission losses. Finally, the Lloyd's mirror effect's coherent interferences are used to (1) compensate the estimated source level considering a fixed vocalizing depth and (2) estimate source depth assuming a constant source level. The method is successfully applied to an individual from both sup-species of interest, based on recordings from the western Indian Ocean. Because it is a single-sensor approach, it can retrospectively be applied to many historical datasets and help expanding source levels and depth databases for blue whales without requiring significant further infrastructure investment.

Mon 13:45 - 14:05
WP4 Technology for Eco-Safe Exploration, Scientific presentation

From seismic-scale outcrop to hand sample: streamlining SfM photogrammetry processing in the geosciences.

Peter Betlem, UNIS

From seismic-scale outcrop to hand sample: streamlining SfM photogrammetry processing in the geosciences.

Peter Betlem1,2, Thomas Birchall1,2, Tereza Mosočiová3, Anna Marie Rose Sartell1,4, Kim Senger1

1Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway
2Department of Geosciences, University of Oslo, Oslo, Norway
3Department of Geological Sciences, Faculty of Science, Masaryk University, Czech Republic
4Department of Geology, Lund University, Lund, Sweden

Structure-from-motion (SfM) photogrammetry enables the cost-effective digital characterisation of targets ranging in size from seismic-scale outcrops to sub-decimetre-scale geoscientific samples. A more quantitative and systematic approach is needed to ensure scientific reproducibility and validity of the generated models.

Here we present an approach that streamlines SfM photogrammetry processing in the geosciences through use of openly available wrapper-scripts for the Agisoft Metashape software suite. The Python-based scripts and runtime logging facilitate ease of use and streamlining of the digitisation process through pre-configured setting files. Such setting files can be finetuned by the user and guide the modelling workflow from ground control point detection to texture generation. The input-free processing is independent of geoscientific sample and allows for batch processing of seismic-scale outcrops and hand-size samples alike, while reducing arbitrary processing decisions associated with the manual processing of point clouds and meshes.

Based on more than 50 data sets the workflow features a success rate of more than 90%, i.e., nine out of ten generated models do not require further processing. Out of the remainder, the majority feature (1) artifacts arising from sub-optimal input data quality (e.g., bad lighting conditions) and/or quantity (e.g., insufficient number of overlapping images, insufficient images with background masks) that equally affect manual processing; and, (2), alignment issues stemming from unoptimized configuration parameters. Batch-processed parameter assessments enable further optimization and improvement of the latter, and provide target-specific (e.g., hand sample, outcrop, etc.) configuration files with optimal parameters for e.g. point cloud and mesh generation as well as confidence cut-off intervals. Finally, the archiving of input data, parameters and the processing log in machine-readable format allows for full reproduction of the results as well as a quantified approach to quality assurance of the final models.

Mon 14:05 - 14:25
WP1&2 Geology, Scientific presentation

Skating on thin ice and other seismic investigations.

Rowan Romeyn, UiT

Skating on thin ice and other seismic investigations.

Rowan Romeyn1, Alfred Hanssen1, Bent Ole Ruud2 & Tor Arne Johansen2, 3

1Department of Geosciences, UiT – The Arctic University of Norway, Tromsø, Norway
2Department of Earth Science, University of Bergen, Bergen, Norway
3The University Centre in Svalbard, Arctic Geology, Svalbard Science Centre, Longyearbyen, Norway

Seismic experiments have been conducted on floating sea ice through ARCEx WP4 and in collaboration with the UNIS course “Arctic Seismic Exploration” over four field seasons. Here we focus on a specific phenomenon common to all of these experiments where explosives have been used as seismic sources. The pressure wave through the air exerts a moving pressure on the ice surface, exciting a flexural wave of a specific frequency that can be related to the flexural stiffness or thickness of the ice. The term “air-coupled flexural wave” was first coined in the 1950’s, but has since received little attention in the scientific literature. We propose that the air-coupled flexural wave phenomenon is simply a special case of the more general paradigm of moving loads on floating plates, where the load speed is equal to the speed of sound in air. The moving load on a floating plate problem, by contrast, has received a great deal of attention from the perspective of vehicular transport. In this presentation, we will highlight the remarkable physical similarity between a group of phenomena ranging from Arctic seismic experiments to wild ice-skating, ice-roads, floating runways, hovercraft, submarines, spaceships and the eruption of Krakatoa.

Mon 14:25 - 14:45
WP4 Technology for Eco-Safe Exploration, Scientific presentation

Wrap up day 1. The host and presenters will take questions from the audience via chat or video before wrapping up for the day.

Tor Arne Johansen, UiB

Mon 14:45 - 15:00
Other

Tuesday 20 Oct 2020

Petroleum geosciences

Welcome to the second day!

Kim Senger, UNIS

Welcome back! Your host will set the scene for the day and introduce the presenters for this session.

Host/moderator: Kim Senger, UNIS, kim.senger@unis.no

Technical facilitator: Ellen Ingeborg Hætta, ellen.i.hatta@uit.no, +47 98801001

Tue 12:30 - 12:35
Other

Depositional trends and fossil preservation in the Middle Triassic of Svalbard.

Victoria Engelschiøn, UiO

Depositional trends and fossil preservation in the Middle Triassic of Svalbard.

Victoria Engelschiøn1, Fredrik Wesenlund2, Jørn Hurum1, Øyvind Hammer1, Atle Mørk3

1Department of Geosciences, University of Oslo, Oslo, Norway
2Department of Geosciences, UiT – The Arctic University of Norway, Tromsø, Norway
3Department of Geoscience and Petroleum, Norwegian University of Science and Technology, Trondheim, Norway

In the Middle Triassic Epoch (247– 237 million years ago), today’s Svalbard was the seabed of a large open marine, shelf sea on the northern rim of Pangea. The sea is known as the Boreal Ocean and was located at a palaeolatitude of approximately 45°N. The depositional environment was coastal to basinal, with the main sediment supply from the southwest. The Middle Triassic sequences can be divided into two distinct depositional provinces: coastal to shallow marine sandstones and shales in the west, and shales and siltstones from the deeper basinal areas in the east. In this study, the focus is on the basinal sediments of the Botneheia Fm. in Central-Spitsbergen and Edgeøya. The aim of the study is to investigate the use of stable carbon isotopes for correlating the sedimentary intervals in the Botneheia Fm. Long-period carbon isotope signals in basin sediments are thought to reflect global patterns. Therefore, time equivalent sedimentary intervals in separate localities can have similar carbon isotope signals. Preliminary results show that the isotope signals in three different localities are following similar trends. Further studies are now ongoing to correlate the sections at the different localities.

References

Vigran, J., Mangerud, G., Mørk, A., Worsley, D. & Hochuli, P.A. 2014: Palynology and geology of the Triassic succession of Svalbard and the Barents Sea. Geological Survey of Norway Special Publication 14, 1-269

Tue 12:35 - 12:55
WP1&2 Geology, Scientific presentation

North Atlantic-Arctic tectonics related to the wider Barents Sea paleogeography and basin evolution.

Mohamed Mansour Abdelmalak, UiO

North Atlantic-Arctic tectonics related to the wider Barents Sea paleogeography and basin evolution

Mansour M. Abdelmalak1, Jan Inge Faleide1,2, Sverre Planke3,1

1Department of Geosciences, University of Oslo, Oslo, Norway
2Department of Geosciences, UiT The Arctic University of Norway, Tromsø, Norway
3Volcanic Basin Petroleum Research AS, Oslo, Norway

The North Atlantic-Arctic region comprises a wide range of crustal structures and sedimentary basins developed as a result of a series of post-Caledonian rift episodes until early Cenozoic time. This complex tectonic history involves a variety of geological processes operating at different temporal and spatial scales and generating a lateral variation on the distribution of the petroleum play elements (reservoirs, source rocks and seals). To understand the evolution and the depositional history of the region, a multidisciplinary approach, including paleogeographic and kinematic reconstructions, should be applied.  Paleogeographic maps are compiled for selected time slices spanning the Late Paleozoic, Mesozoic and Cenozoic to present day. Older versions of paleogeographic maps from both sides of the Norwegian-Russian border are combined and updated with more recent data records. These include new data from boreholes, seismic surveys and provenance studies.

For the kinematic reconstructions, the post-Caledonian history of the region has been largely dominated by rifting as well as major extrusive and intrusive magmatic emplacements. Greenland has a key position within the North Atlantic Arctic transition, its evolution is a key piece for understanding the kinematic evolution, and to address the question of how Paleogene breakup in the Arctic and North Atlantic was linked. To reconstruct the basin evolution and construct well-constrained paleogeographic/-tectonic maps we have to quantify the pre-drift extension through time and space. This is done by tectonic modelling and margin restoration where the observed geometry of crustal thinning is compared to a reference thickness of the crystalline crust close to onshore areas, which have experienced limited or no crustal extension since Late Paleozoic time.

The establishment of new and updated paleogeographic maps enable better constraints on the regional basin evolution and sediment provenance (source-to-sink), including the role of structural inheritance, varying regional stress fields of the North Atlantic- Arctic region.

Tue 12:55 - 13:15
WP1&2 Geology, Scientific presentation

Linking facies descriptions, total organic carbon and bitumen richness – a case study from the Middle Triassic black shales of eastern Svalbard.

Fredrik Wesenlund, UiT

Linking facies descriptions, total organic carbon and bitumen richness – a case study from the Middle Triassic black shales of eastern Svalbard.

Fredrik Wesenlund1, Olaf Thiessen2, Victoria S. Engelschiøn3, Jon Halvard Pedersen4, Sten-Andreas Grundvåg1

1Department of Geosciences, UiT – The Arctic University of Norway, Tromsø, Norway
2Equinor ASA, Harstad, Norway
3Natural History Museum, University of Oslo, Oslo, Norway
4Lundin Energy Norway, Norway

The Middle Triassic Botneheia Formation is generally considered the best source rock in the northern Norwegian Barents Sea. Still, no study has investigated the integrated stratigraphic relationship between total sulfur, organic carbon, and bulk bitumen composition tied to mudrock facies in these organic-rich shales. This study investigates and links these properties to published paleo-depositional environments based on two complete, thermally mature sample profiles of the Botneheia Formation in eastern Svalbard, incorporating the most recent lithostratigraphic framework. The Botneheia Formation consists of the Muen Member (Anisian) and the overlying Blanknuten Member (Ladinian). The results show that total sulfur, organic carbon, bitumen richness, and aromatic hydrocarbon content increase from the grey-colored shales in the Muen Member upwards into the organic-rich, black shales in the middle part of the Blanknuten Member. From here, organic carbon and bulk bitumen richness subsequently decrease upwards in concert with the occurrence of bioturbated, calcareous mudrocks and impure limestones in the upper part of the unit. These chemostratigraphic trends and developing mudrock facies appear to be closely related to reported pan-arctic Middle Triassic transgressive–regressive sequences, and further support the presence of a maximum flooding surface in the middle Blanknuten Member. Multivariate analyses of the geochemical data show that the geochemical signature of the lower to middle part of the Muen Member are similar to the much younger Carnian Tschermakfjellet Formation immediately above the oil prone, black shales of the Blanknuten Member. This indicates that; (i) the lower to middle Muen Member was deposited during oxic and/or dysoxic conditions or; (ii) the lowermost part of the Carnian Tschermakfjellet Formation was influenced by dysoxic conditions in eastern Svalbard. These findings provide new insights towards paleo-depositional development and source rock properties of the Middle Triassic organic rich shales in the northern Norwegian Barents Sea.

Tue 13:15 - 13:35
WP1&2 Geology, Scientific presentation

Coffee break

The host and presenters will hang around and answer your questions directly via chat or video before we continue the session after the break.

Tue 13:35 - 13:45
Break

Permafrost trapped natural gas - a ticking time bomb or potential energy source?

Thomas Birchall, UNIS

Permafrost trapped natural gas - a ticking time bomb or potential energy source?

Thomas Birchall1,2, Peter Betlem1,2, Kim Senger1, Andrew Hodson1, Malte Jochmann1,3, Snorre Olaussen1

1Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway
2Department of Geosciences, University of Oslo, Oslo, Norway
3Department of Earth Science, University of Bergen, Bergen, Norway

Permafrost has become an important subject in recent years and in Svalbard it has been the focus of countless studies, with the majority focusing on the uppermost metres, i.e. the active layer. Despite this, the processes directly beneath the permafrost are poorly understood. This is arguably due to the lack of recent data collected through the permafrost interval. However, hundreds of coal and petroleum exploration wellbores have penetrated the base of permafrost since mining began near the start of the twentieth century. In 1967 a coal exploration well in Adventdalen discovered a gas accumulation at the base of permafrost that flowed intermittently for more than seven years. We carried out further investigations of these industrial and scientific wellbores and found that gas accumulations at the base of permafrost are surprisingly common in Svalbard. For context: of eighteen hydrocarbon exploration wells drilled on Svalbard between 1961 to 1994, half of them show good evidence of permafrost. Of these 50% would be considered accidental but technical successes due to the presence of moveable hydrocarbons directly beneath permafrost.

Further findings have also come to light from this review, some of which are contrary to presently held beliefs:

  • Sub-permafrost aquifers demonstrably flow at much greater rates than present publications suggest
  • Gas from Hopen sits well within the gas hydrate stability zone, which is significant with respect to how much gas volume can be held in the accumulation
  • Relatively thick coastal permafrost exists on Spitsbergen’s east coast
  • Permafrost is likely ice-deficient in highlands, but ice-saturated and impermeable in valleys

The frequency and relatively large size of these accumulations has some implications. Firstly, permafrost is only a few kyrs old, the presence of trapped thermogenic gas is evidence of ongoing migration in an active petroleum system. Secondly, permafrost is thawing in the arctic and methane is a greenhouse gas. Understanding the thawing rate and regional volumes of these accumulations is important in understanding potential climatic feedback effects. Secondly, Longyearbyen and Barentsburg are powered by coal. If the gas accumulations are as common and significant as these findings suggest, could natural gas from the base of permafrost represent an alternative source of energy?

Figure 1 – Schematic permafrost trapping mechanisms in Svalbard

Tue 13:45 - 14:05
WP1&2 Geology, Scientific presentation

Seal Characterization and Seal Integrity in Uplifted Basins on the Barents Shelf, the Greater Hoop Area.

Renate S. Paulsen, UiT

Seal Characterization and Seal Integrity in Uplifted Basins on the Barents Shelf, the Greater Hoop Area.

Renate Strugstad Paulsen1, Sten-Andreas Grundvåg1, Kim Senger2, Eirik Stueland3

1Department of Geosciences, UiT - The Arctic University of Norway, Tromsø, Norway
2Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway
3OMV (Norge), Stavanger, Norway

Several discoveries in the uplifted Hoop area on the Barents Shelf has proven that unconventional plays in areas subject to severe exhumation may still hold significant amounts of hydrocarbons. A functioning cap rock is essential for any accumulations of fluids in the subsurface, and is therefore one of the vital risk factors in exploration. Embrittlement and change in mechanical behaviour of deeply buried mudrocks, which have later undergone severe uplift, may have large implications on the seal- and trap integrity of potential plays. This project analyses seismic and well-log data from the uplifted basins in the Hoop area on the Barents Shelf, focusing on the regional cap rock units of the Upper Jurassic Fuglen and Hekkingen formations. The formations represent basin-wide shale-rich units with various total organic carbon (TOC) content, with the Hekkingen Formation considered to be one of the main source rocks on the shelf. In particular, the in-situ mechanical behaviour has been investigated through acoustic impedance and density data from the well logs. The empirical equations from log-derived elastic properties indicates a relationship and good correlation between themselves that could be useful for seal integrity analysis. By analysing the brittle-ductile response through elastic properties from the well logs, it is possible to correlate data from nearby wells in the Hoop area in order to establish whether there exist a correlation between elastic parameters and mudrock behaviour. The analysis indicates a relationship between intervals with higher TOC, less heterogeneity in the lithology and the integrity for both formations. Additionally, regional changes in lithology affecting the acoustic signatures show similar relationships, and that the elastic parameters changes with increasing/decreasing mud content.

Tue 14:05 - 14:25
WP1&2 Geology, Scientific presentation

Presalt Carboniferous basin architecture, salt tectonics and basin modeling providing new exploration insights in the Nordkapp Basin, SW Barents Sea.

Muhammad Hassaan, UiO

Pre-salt Carboniferous basin architecture, salt tectonics and basin modelling providing new exploration insights in the Nordkapp Basin, SW Barents Sea

Muhammad Hassaan1, Jan Inge Faleide1, Roy Helge Gabrielsen1, Filippos Tsikalas2,1

1Department of Geosciences, University of Oslo, Oslo, Norway
2Vår Energi AS, Stavanger, Norway

Reprocessed regional 2D seismic reflection profiles, 3D seismic data, available wells, and gravity and magnetic data were used to study the enigmatic Nordkapp Basin. The basin evolved over the interference between Timanian and Caledonian basement structures with the Caledonian “Middle Allochthonous Front” passing through the central segment of the Nordkapp Basin and creating a transition between the two structural grains. The rheological properties, locations, orientations and interaction of the Timanian and Caledonian structural grains, strongly influenced the shallower pre-salt rift architecture. During the late Devonian-early Carboniferous NE-SW oriented extensional phase, the northeastern, central and southwestern segments of the Nordkapp Basin were parts of two, one northern and one southern, regional half-grabens that were separated by a prominent interbasin ridge. During the late Carboniferous-early Permian, the shift of the extensional stress axis (s3) from NE-SW to NW-SE re-shaped the two regional half-grabens. In particular, a transfer fault, with character of an interbasin transfer zone, divided the northern regional half-graben by separating the hinged-margin (incipient northeastern segment) from the deeper part (incipient central segment). At the same time, the interbasin ridge acted as a transfer zone and created a partition between the central and southwestern segments. The contrasting Timanian and Caledonian structural grains and the two extensional phases gave rise to seven sub-basins in the Nordkapp Basin. We suggest that the top of the accumulated layered evaporitic sequences (LES) defined an irregular surface inherited the preceding extension and it possessed some relief mimicking the underlying rift architecture. The residual topographic expression has, in turn, influenced the earliest Triassic progradational sediment routings and dictated both where the initial deposition could take place and the distinct depositional fairways. However, the progradational deltaic system from the east dominated the interplay between the LES and the rift architecture within the Nordkapp Basin.

Tue 14:25 - 14:55
WP1&2 Geology, Scientific presentation

Wrap up day 2. The host and presenters will take questions from the audience via chat or video before wrapping up for the day.

Kim Senger, UNIS

Tue 14:55 - 15:10
Other

Wednesday 21 Oct 2020

Environmental risk management

Welcome to day three!

JoLynn Carroll, Akvaplan-niva

Welcome back! Your host will set the scene for the day and introduce the presenters for this session.

Host/moderator for the day: JoLynn Carroll, jlc@akvaplan-niva.no

Technical facilitator: Ellen Ingeborg Hætta, ellen.i.hatta@uit.no, +47 98801001

Wed 12:30 - 12:35
Other

Pelagic ecosystem dynamics between late autumn and the post spring bloom in the high latitude Kaldfjorden.

Ingrid Wiedmann, UiT

Pelagic ecosystem dynamics between late autumn and the post spring bloom in the high latitude Kaldfjorden.

Ingrid Wiedmann1, E. Zoe Walker, Angelika H. H. Renner2, Anna Nikolopoulos2, Jofrid Skarðhamar2

1Department of Arctic and Marine Biology, UiT – The Arctic University of Norway, Tromsø, Norway
2Institute of Marine Research, Oceanography and climate, Tromsø, Norway

High latitude fjord ecosystems experience an increasing level of human activity throughout the year, including the little studied winter. To improve the knowledge base for sustainable management in all seasons, the present study provides hydrographic and biological baseline data from Kaldfjorden, Northern Norway (69.7° N, 18.7° E) between late autumn 2017 to spring 2018. By integrating field observations with results of a hydrodynamic model simulation, we illustrate how pelagic biomass (chlorophyll a (Chl a), particulate organic carbon (POC), and zooplankton) are affected by hydrographic drivers in this period. An unusually warm autumn delayed the onset of autumn cooling and likely supported the observed high abundances of zooplankton (5 768 individuals m-3), and meroplankton in particular. With the onset of winter, the water cooled and became vertically mixed, while the concentration of suspended biomass dropped (< 0.12 mg Chl a m-3). However, in January and February the concentration of suspended and exported POC close to the sea floor was elevated. As in these months, the hydrodynamic model results show the strongest deep currents of the study period we presume that pronounced resuspension took place. In the spring, peak abundances of suspended biomass were found (April, 5-15 m: 6.9-7.2 mg Chl a m-3, 100-0 m: 9952 zooplankton ind. m-3), and field observations and model results suggest that zooplankton were advected into Kaldfjorden by Atlantic-derived waters. In addition, the model simulation suggests a complex circulation pattern even in a small fjord, which can have implications for the fjord management. We conclude that the pelagic system in Kaldfjorden continually changes from autumn to spring and that it is important to see winter as a dynamic period and not as a season where the fjord ecosystem is ‘at rest’.

Wed 12:35 - 12:55
WP3 Environmental Risk Management, Scientific presentation

Parental exposure to crude oil on fertilization success and embryo development in Atlantic cod.

Claudia Erhart, UiT

Parental exposure to crude oil on fertilization success and embryo development in Atlantic cod.

Claudia Erhart1, Jasmine Nahrgang1, Marianne Frantzen2, Bjørn Henrik Hansen3, Øyvind Hansen4, James Meador5, Velmurugu Puvanendran4, Helena Reinardy6,7, Lisbet Sørensen3

1Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
2Akvaplan-niva, Fram Centre, Tromsø, Norway
3SINTEF, Trondheim, Norway
4Nofima, Tromsø, Norway
5NOAA Fisheries, Seattle WA, USA
6Scottish Association for Marine Science, Oban, UK
7The University Centre in Svalbard, Longyearbyen, Norway

The impact of petroleum activities on the marine environment and, in particular, the consequences on fish stocks and fisheries have been a central issue in Norway since the 1970s. One of the key questions is to understand how exposure to petroleum compounds affects different life stages of fish. Considering the scarcity of data existing on transgenerational impacts of crude oil exposure, the present study aims to fill this knowledge gap using Atlantic cod, an important commercial fish species. This project investigates the transfer of crude oil compounds from maternal exposure to oocytes and the effect of parental exposure on gamete quality as well as embryo development. In particular, the individual contaminant accumulation in oocytes is determined and subsequent effects on embryo development are investigated. Additional focus is given to study effects of altered gamete quality on later developmental stages. Therefore, mature fish were exposed to the water soluble fraction of crude oil prior to spawning using a standard oiled gravel column set up. In the following, fish were stripped and in vitro fertilized eggs were reared under control conditions. Bioaccumulation of crude oil compounds in oocytes as well as sperm quality and fertilization success are determined. In addition, biotransformation capacity, epigenetic alteration, and genotoxicity will be characterized in embryos and larvae using molecular analyses. Furthermore, hatching success and apical endpoints in larvae, including malformations and cardiotoxicity, will be studied. This work will provide insight into the thus far little researched field of transgenerational effects of crude oil exposure in fish. Determining the potential risk of parental transfer to offspring and the effects on subsequent generations is of great importance for a holistic understanding of the risk from accidental oil spills.

Wed 12:55 - 13:15
WP3 Environmental Risk Management, Scientific presentation

Oil spill response options from a shrimp`s perspective.

Frederike Keitel-Gröner, NORCE

Oil spill response options from a shrimp’s perspective

Frederike Keitel-Gröner, Renée K. Bechmann, Thierry Baussant
NORCE Norwegian Research Centre, Randaberg, Norway

Climate change promotes oil exploration and shipping activities in the Arctic. Consequently, the risk for accidental oil spills increases and technologies such as use of dispersants or in-situ burning are considered for response actions to mitigate the environmental consequences, should an accident occur. The objective of this research is to support decision-making selecting the response options that minimize the impacts on marine organisms. We selected the Northern shrimp (Pandalus borealis) to investigate acute (mortality) and chronic (feeding, growth, development) effects of these response options. P. borealis larvae are planktonic, while adults are benthic. It is an important species in the North Atlantic food web and of commercial value for local fisheries. First, we compared the effects of mechanically and chemically dispersed oil on planktonic stages of shrimp. Then, we investigated the effects of field generated burned oil residue on larvae. From these experiments, it was concluded that in-situ burning is the oil spill clean-up action with the least impact, over mechanical dispersion, and that chemical dispersion was most harmful for planktonic stages. We also studied effects of long-term exposure of adults to petroleum hydrocarbons leaking from sediment coated with burned oil residue or crude oil. The residue treatment did not cause any acute or chronic effects, while oil exposure temporary reduced feeding, increased PAHs body burden and delayed development in larvae exposed as embryos. Different petroleum hydrocarbon concentrations, compositions, and oil availability (soluble or dispersed) in the exposures likely explain the findings. Further, it appeared that effects were not entirely related to PAHs exposure only. Overall, these data are contributing to identify threshold levels of effects on both pelagic and benthic life stages of a key sub-arctic species to be used in a Net Environmental Benefit Approach (NEBA) by oil spill responders.

This research is funded by ARCEx partners and the Research Council of Norway (grant number 228107) with additional funding from NOFO.

Wed 13:15 - 13:35
WP3 Environmental Risk Management, Scientific presentation

Coffee break

The host and presenters will hang around and answer your questions directly via chat or video before we continue the session after the break.

Wed 13:35 - 13:45
Break

Current status of SYMBIOSES.

Mathias Bockwoldt, UiT

Current status of SYMBIOSES.

Mathias Bockwoldt1, JoLynn Carroll1,2

1Department of Geosciences, UiT – The Arctic University of Norway, Tromsø, Norway
2Akvaplan-niva, Fram Centre, Tromsø, Norway

Since 2012, the SYMBIOSES project (System for biology-based assessments) has been creating a modelling system designed to support the practical application of ecosystem-based management as an effective management approach for fisheries and offshore petroleum activity. The SYMBIOSES system connects individual models into a computational framework located on a supercomputer. It is designed to simulate marine ecosystem components in space and time and predict impacts from selected combinations of fisheries and petroleum operations.

The project is now in its third phase. There are many improvements to be implemented in the system, but also technical challenges to tackle. A huge step will be the transition from the old, local supercomputer “Stallo” to the new, national supercomputer “Saga”. Better hardware and software will speed up the simulations. Using the more powerful computer, we can introduce more fish species that can be simulated simultaneously. In addition, the simulated area of the ocean will be increased, allowing for a better follow-up of fish larvae that leave the coast of Norway. We will also update the oil chemistry and transportation model to its latest version, yielding a closer connection to the hydrodynamic model and a better numerical precision. The calculation of the influence of chemical compounds on larval growth and survival will be completely rewritten, using a dynamic energy budget approach that is more realistic and that allows for a much more transparent evaluation of the results.

Overall, the new system will be faster, larger, more versatile and contain more fish species than ever, giving us an even better tool to assess petroleum industry endeavours along the Norwegian coast.

Wed 13:45 - 14:05
WP3 Environmental Risk Management, Scientific presentation

Large whale acoustic behavior in Lofoten-Vesterålen recorded by autonomous systems.

Sofia Aniceto, UiT/VISTA

Large whale acoustic behavior in Lofoten-Vesterålen recorded by autonomous systems.

Ana Sofia Aniceto1, Geir Pedersen2, Sunnje Basedow3, Lionel Camus4

1Department of fisheries and bioeconomics, UiT The Arctic University of Norway, Tromsø, Norway
2Department of marine ecosystem acoustics, Norwegian Institute of Marine Research, Bergen, Norway
3Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway 
4Akvaplan-niva AS, Fram Centre - High north center for climate and the environment, Tromsø, Norway

High latitude regions are experiencing rapid environmental changes. The Lofoten-Vesterålen shelf of northern Norway sustains a high diversity of seasonal and resident species of soniferous animals, vulnerable to the effects of climate change and increasing anthropogenic activities. Still, data on indicators of ecosystem health, such as cetaceans, remains scarce. Autonomous systems are excellent platforms for systematic monitoring, unbound by safety and cost constraints, with minimal disturbance to the animals. We examine patterns of acoustic activity of cetaceans recorded by an Autonomous underwater vehicle and an ocean observatory. We deployed a passive acoustic sensor system onboard a SeagliderTM during spring over two consecutive years to determine animal distribution, social and reproductive interactions, and foraging activity. The LoVe Ocean Observatory, also equipped with a passive acoustic system, provided temporal context to the observations of baleen and odontocete species. We observed a change in cetacean detections throughout the study period, with humpback whale calls and fin whales dominating the soundscape in early spring. Sperm whales and delphinids are more predominant in late spring, engaged in foraging activity. In late spring, sounds of seismic airguns were found despite no prospecting activity being reported in the area. Our results provide the first stages of consideration for top-predator activity in high latitude soundscapes. As vital components of the ecosystem, cetacean behaviour and distribution can provide insights into the marine environment, valuable for management strategies. Effective management of anthropogenic activities in the marine environment requires successful and efficient data collection, for which autonomous systems play a major role, as demonstrated in this study.

Wed 14:05 - 14:25
WP3 Environmental Risk Management, Scientific presentation

Masking effects of seismic airguns on baleen whale communication.

Hannah Kriesell, NTNU

Masking effects of seismic airguns on baleen whale communication.

Hannah Kriesell, Léa Bouffaut, Martin Landrø

Department of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway

Previous studies studied the impacts of airgun blasts during seismic acquisition on cetaceans and have described avoidance behaviour, changes in vocalization rates, and auditory masking effects. Most of the work focused on behavioral responses based on visual observations or experimentally acquired hearing thresholds or temporary threshold shifts. Meanwhile, recent geophysical studies provide new insights into physical aspects of seismic sound generation and propagation, e.g. the emission of high frequencies 5kHz) resulting from ghost cavitation and frequency dependent amplitudes of air gun arrays fired at long distances (10 100 km) with increasing water depth.

To understand potential masking effects of airgun noise on blue whale vocalizations in deep waters, we modeled the vocalization signal that a conspecific blue whale would be exposed to in a scenario where an airgun is being fired. The airgun source signals were acquired during a seismic test survey where the shooting vessel was equipped with three conventional air gun subarrays, and several shot lines crossing vertically above a stationary hydrophone permanently placed at the seafloor. Antarctic blue whale signals are chosen for the simulations because of the simplicity of their time frequency contours as they can be modeled as a sigmoid function with adjustable parameters. The received signal is then generated based on a geometrical propagation model, considering the bathymetry and sound profile of the area of interest. The model results are further interpreted using audiograms of baleen whales taken from the literature to make assumptions about the audibility of the seismic shooting and the conspecific blue whale call that underwent acoustic masking.

 

Wed 14:25 - 14:45
WP4 Technology for Eco-Safe Exploration, Scientific presentation

Wrap up day 3. The host and presenters will take questions from the audience via chat or video before wrapping up for the day.

JoLynn Carroll, Akvaplan-niva

Wed 14:45 - 15:00
Other

Thursday 22 Oct 2020

Petroleum geosciences continued

Welcome to the final day!

Sten-Andreas Grundvåg, UiT

Welcome back! Your host will set the scene for the day and introduce the presenters for this session.

Host/moderator for the day: Sten-Andreas Grundvåg, sten-andreas.grundvag@uit.no

Technical facilitator: Ellen Ingeborg Hætta, ellen.i.hatta@uit.no, +47 98801001

Thu 12:30 - 12:35
Other

Onshore-offshore correlations of the Billefjorden fault zone, Svalbard.

Aleksandra Smyrak-Sikora, UNIS

Onshore-offshore correlations of the Billefjorden fault zone, Svalbard.

Aleksandra Smyrak-Sikora1, Alvar Braathen2, Tormod Henningsen3, Julian Janocha3, Erik P. Johannessen4, Gareth Lord1, Snorre Olaussen1, Kim Senger1, Camilla L. Würtzen2

1Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway
2Department of Geosciences, University of Oslo, Oslo, Norway
3 Department of Geology, UiT The Arctic University of Norway, Tromsø, Norway
4EP Skolithos, Stavanger, Norway
4Department of Geoscience and Petroleum, Norwegian University of Science and Technology, Trondheim, Norway

The Billefjorden Fault Zone (BFZ) is a long-lived structural lineament that displays deformation originating during the Caledonian orogeny, followed by the Devonian collapse and shortening and the Carboniferous rifting. Following Mesozoic deformation downturn, the lineament was reactivated during the Paleogene transpressional Eurekan event. The BFZ consists of several north-south striking segments dipping east with sub-ordinary segments dipping south east. It outcrops in central Spitsbergen and can be traced in geophysical datasets. In this study, we integrate field-based datasets (e.g., sedimentary facies, structural measurements, geological mapping and the acquisition of digital outcrop models) with offshore and subsurface datasets (e.g., 2D seismic profiles, gravity and magnetic maps and coal and petroleum borehole data). We focus on fault control over segmentation of pre-rift Lower Carboniferous deposit of the Billefjorden Group, and on the deposition of Bashkirian and Moscovian syn-rift succession belonging to the Billefjorden Trough.

The onset of rifting records a transition from humid into arid conditions and a shift from coal-bearing fluvial sediments to a mixed siliciclastic, evaporitic and carbonaceous terrestrial and shallow-marine succession. Among new findings, we introduce the Mimerbukta fault- a major syn-rift fault discovered south of Pyramiden. The Mimerbukta fault strikes north-south and juxtaposes the early syn-rift, terrestrial red shales in the footwall against late syn-rift, marine to paralic gypsum and carbonate deposits in the hanging wall. Detailed mapping of faults and sedimentary facies along the BFZ allows the construction of a 3D model and to reveal fault evolution and the impact upon the distribution of sedimentary facies belts. The results of this study allow (i) to discuss the limitations and strengths of diverse datasets (ii) map a complex structural and sedimentological architecture of master fault zone that can help to increase predictability of diverse petroleum system elements, such as segmentation of source and reservoir rocks including juxtaposition relations against the faults and fault sealing potential.

Thu 12:35 - 12:55
WP1&2 Geology, Scientific presentation

The Norian to Bathonian reservoir interval of Svalbard and examples of correlation to the northern Barents Sea.

Gareth Lord, UNIS

The Norian to Bathonian reservoir interval of Svalbard and examples of correlation to the northern Barents Sea.

Gareth S. Lord, Snorre Olaussen, Kim Senger

Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway

The Rhaetian to Bathonian succession of Svalbard comprises the Wilhelmøya Subgroup. We discuss the regional development of this interval throughout Svalbard and compare the unit’s characteristics with its equivalent unit, the prolific hydrocarbon bearing Realgrunnen Subgroup in the Barents Sea.

Facies changes and variations in formation thickness shed light on the regional development of the Wilhelmøya Subgroup throughout the Svalbard archipelago. We focus on outcrop data from southern Oscar II Land, central Spitsbergen, Eastern Spitsbergen, Wilhelmøya, Kong Karls Land and Hopen. In addition, the development of the subgroup is discussed with regards to well and core data from the Sentralbanken area of the northern Barents Sea.

Thu 12:55 - 13:15
WP1&2 Geology, Scientific presentation

Miocene sedimentary environments on the northern Mid-Norwegian continental margin.

Stine Bjordal Olsen, UiT

Miocene sedimentary environments on the northern Mid-Norwegian continental margin.

Stine Bjordal Olsen1, Tom Arne Rydningen1, Jan Sverre Laberg1, Amando Lasabuda1, Stig-Morten Knutsen2,1

1Department of Geosciences, UiT – The Arctic University of Norway, Tromsø, Norway
2The Norwegian Petroleum Directorate, Harstad, Norway

The Miocene evolution of the northern part of the Mid-Norwegian margin is studied using a dense grid of 2D seismic data together with results from exploration wells on the Vøring margin.

The earliest Cenozoic evolution involves rifting, opening and seafloor spreading in the Norwegian-Greenland Sea, which created accommodation space in a marine to shallow-marine setting on this margin. Low to moderate amplitude parallel-layered reflections in the Miocene Kai Formation is interpreted to represent deep-water hemipelagic deposition in the Vøring Basin.

Although the Norwegian-Greenland Sea deepened and widened as seafloor spreading evolved, the Mid-Norwegian margin experienced compressional forces during the Cenozoic. This caused doming along the Norwegian-Greenland Sea basin margin, which largely affected the depositional pattern of the Kai Formation. Very thin deposits characterize the dome crests, whereas thicker accumulations fill in the basins between the domes. These accumulations typically have elongated shapes oriented in a SSW-NNE direction. The largest accumulation is present on the slope and is ~200 km long, between 40 and 110 km wide and up to ~520 m thick. A pronounced divergent reflection configuration with associated moat structures characterize these elongated accumulations. Progressive onlap are typical for their upslope reflection terminations, while low-angle downlap often characterize the downslope terminations. These characteristics are altogether typical of contourites deposited from ocean currents, indicating the presence of a well-established oceanic circulation with a persistent current direction along the Norwegian margin during deposition of the Kai Formation.

Eastwards of the Kai Formation, steeply dipping clinoforms of the Molo Formation testify to a coastal outbuilding. An internal chaotic seismic facies on the lower slope suggest that parts of the Molo Formation has failed.

Thu 13:15 - 13:35
WP1&2 Geology, Scientific presentation

Coffee break

The host and presenters will hang around and answer your questions directly via chat or video before we continue the session after the break.

Thu 13:35 - 13:45
Break

Cenozoic evolution of the northern Barents Sea-Svalbard Area.

Maximilian Weber, UiT

Cenozoic evolution of the northern Barents Sea-Svalbard Area.

Maximilian Weber1, Jan Sverre Laberg1, Amando Lasabuda1, Sten-Andreas Grundvåg1, Stig-Morten Knutsen2,1, Tom Arne Rydningen1

1Department of Geosciences, UiT The Arctic University of Norway, Tromsø, Norway
2Norwegian Petroleum Directorate, Harstad, Norway

The Arctic is one of the last geological frontier areas and a main driver of the climate system of our earth. Within the Arctic, the Fram Strait, the ocean gateway between Svalbard and Greenland, is of importance for our modern climate system. Exchange of deep water between the Arctic Ocean and the North Atlantic is only possible through this gateway. Even though, it is known that the Fram Strait emerged as the product of Greenland and Svalbard separating from each other during the Paleogene, the precise timing and exact sequence of opening is still poorly understood. The opening and deepening had major implications on the paleoclimatic evolution towards the climate system of the present. A key area to understand this process of opening is located on the eastern side of the Fram Strait: the West Spitsbergen continental margin and the adjacent Yermak Plateau. This study aims to characterize the geological history of the West Spitsbergen continental margin and the Yermak Plateau during the entire Cenozoic with emphasis on erosion and deposition as a response to the paleoclimatic and tectonic evolution of the area, and the potential causes such as source area uplift and continental margin subsidence. Svalbard, representing the emerged part of the Barents Shelf, has undergone the most uplift on the entire shelf. The amount and timing of uplift and erosion can help to distinguish between different sorts of uplift induced by tectonism, isostatic rebound or other mechanisms. This project will incorporate 2D seismic and well data, as well as outcrop analogues (primarily from the exhumed margins of the Forlandsundet Graben in western Svalbard) with the ultimate goal to reconstruct the Cenozoic paleoenvironment and quantify the amount of Cenozoic uplift and erosion through estimation of the deposited sediment volume (i.e. mass balance calculations).

Thu 13:45 - 14:05
WP1&2 Geology, Scientific presentation

Lower Cretaceous source rocks, SW Barents Sea.

Andreas Hagset, UiT

Lower Cretaceous source rocks, SW Barents Sea.

Andreas Hagset1, Sten-Andreas Grundvåg1, Balazs Badics2, Roy Davies2, Atle Rotevatn

1Department of Geosciences, UIT The Arctic University of Norway, Tromsø, Norway
2Wintershall Dea Norge, Stavanger, Norway
3Department of Earth Science, University of Bergen, Bergen, Norway

The presence of a thermal mature and viable source rock (SR) is one of the key risk factors in exploration. Across the Norwegian Continental Shelf, Upper Jurassic black shales has traditionally been given most attention. Despite its wide distribution on the SW Barents Shelf, the Upper Jurassic Hekkingen Formation only appear to be oil-mature in a narrow belt along the western margin of the Hammerfest Basin and the Loppa High. The presence of alternative SR units is therefore crucial for exploration success in these frontier areas.

By combining high-resolution regional 2D data, well logs, and a digitalized Rock-Eval database, this study aim to map the lateral and stratigraphic distribution and variability of potential SR units within the Lower Cretaceous succession in the marginal basins on the SW Barents Shelf.

Our findings suggest that a lower Aptian SR unit may be viable in the shallow Fingerdjupet Subbasin, Hammerfest Basin and Bjørnøya Basin. However, several factors limit its lateral extent and accumulation potential. Among these are the structural delimitation as these units accumulated in active rift basins. Periods of anoxia and relative high sedimentation rates are key processes in these restricted basins in order for accumulation and preservation to take place.

A Barremian SR unit is present in the southern parts of Bjørnøya Basin and the Hammerfest Basin. This SR unit show good potential in a few wells, but is relatively thin and strongly affected by faulting and segmentation along the major fault complexes (e.g. RLFC, BFC, and LFC). Its greatest potential is confined to depocenters in the Hammerfest Basin and areas that are structurally restricted.

The Bjørnøya and Tromsø basins underwent significant subsidence during the Late Jurassic–Early Cretaceous rift phase. The Barremian and lower Aptian SR unit is consequently over-mature and difficult to interpret. Instead, a Cenomanian SR unit could provide an alternative source for hydrocarbon generation in these deep basins.

Thu 14:05 - 14:25
WP1&2 Geology, Scientific presentation

The Paleocene succession in Svalbard – summary and new insights into an initial foreland basin.

Malte Jochmann, UNIS

The Paleocene succession in Svalbard – summary and new insights into an initial foreland basin.

Malte Jochmann1,2, Snorre Olaussen1, Maria Jensen1

1The University Centre in Svalbard, Arctic Geology, Svalbard Science Centre, Longyearbyen, Norway
2Department of Earth Science, University of Bergen, Bergen, Norway

The Paleocene succession in Svalbard represents the initial depositional cycle of a major foreland basin (Bruhn and Steel 2003) which was formed in response to Eurekan orogeny in the Arctic.

We made an updated reconstruction of the basal units (Firkanten, Basilika and Grumantbyen formations) based on existing data and unpublished borehole and outcrop data. The lowest unit, the paralic deposited Todalen Member is resting on a well-defined transgressive surface lag. A tephra layer can be used as isochronous marker horizon and be traced for more than 100 km along an early Selandian shoreline. The Paleocene succession comprises several regional correlative surfaces represented by subaerial -, transgressive-, maximum flooding and maximum regressive surfaces.

The overall picture shows a SW-NE-backstepping overall transgressive succession. The scale of the units, the thickness of some of the facies association and recent observation north of Isfjorden (Jochmann et al. 2019) showing link northwards of the Paleocene succession, suggests a basin whose extend goes far beyond the preserved Central Tertiary Basin (CTB) of Spitsbergen.

Reference:

Bruhn, R. & R. Steel (2003) High-resolution sequence stratigraphy of a clastic foredeep succession (Paleocene, Spitsbergen): an example of peripheral-bulge-controlled depositional architecture. Journal of Sedimentary Research, 73, 745-755.

Jochmann, M. M., L. E. Augland, O. Lenz, G. Bieg, T. Haugen, S. A. Grundvåg, M. E. Jelby, I. Midtkandal, M. Dolezych & H. R. Hjálmarsdóttir (2019) Sylfjellet: a new outcrop of the Paleogene Van Mijenfjorden Group in Svalbard. arktos.

Thu 14:25 - 14:45
WP1&2 Geology, Scientific presentation

Wrap up and closing remarks.

Sten-Andreas Grundvåg, UiT

Thu 14:45 - 15:00
Other