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Amundsen, Madelen; Hammer, Øyvind & Nakrem, Hans Arne
(2023).
Massedød hos trilobitter, ordovicium, Marokko.
Stein.
ISSN 0802-9121.
2023(4),
s. 18–22.
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Hurum, Jørn Harald; Hammer, Øyvind; Friis, Henrik; Müller, Axel; Engelschiøn, Victoria Sjøholt & Strøm, Marianne
(2023).
En kort veiledning for de nye utstillingene i Geologisk hus, Naturhistorisk museum, Universitetet i Oslo.
Stein.
ISSN 0802-9121.
s. 3–13.
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Zuchuat, Valentin; Augland, Lars Eivind; Jones, Morgan Thomas; Sleveland, Arve R.N.; Twitchett, Richard & Tovar, Francisco J Rodríguez
[Vis alle 13 forfattere av denne artikkelen]
(2022).
The Permian-Triassic boundary across the Barents Shelf: an intricate record of climate change, mass extinction, recovery, and basin reorganisation.
EGU General Assembly.
doi:
10.5194/egusphere-egu22-2379.
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Delsett, Lene Liebe; Pyenson, Nicholas; Miedema, Feiko & Hammer, Øyvind
(2022).
The hyoid arch and feeding in two fish-shaped marine tetrapods.
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Zuchuat, Valentin; Augland, Lars Eivind; Jones, Morgan Thomas; Twitchett, Richard; Rodríguez-Tovar, Francisco J. & Hammer, Øyvind
[Vis alle 11 forfattere av denne artikkelen]
(2021).
Facies changes, volcanism, and mass extinction conundrum: the Permian-Triassic boundary across the Barents Sea Shelf.
Vis sammendrag
The most dramatic mass extinction the Earth has ever experienced occurred 252 million years ago, at the end of the Permian. It was likely triggered by the volcanic eruptions and magmatic intrusions associated with the Siberian Traps Large Igneous Province (LIP), leading to dramatic climatic changes, with consequences lasting well into the Early Triassic.
Here, we present a summary of the findings from the study of several sedimentary successions distributed across the Barents Sea that spanned the End Permian Mass Extinction (EPME) and the Permian-Triassic boundary. The four studied successions included the renowned Festningen section in the outer part of Isfjorden, western Spitsbergen; the DD-1 core and the associated river section in Deltadalen, central Spitsbergen; a core drilled offshore Kvitøya in northern Svalbard, and a core drilled on the Horda Platform in the Barents Sea. Datasets of various research lines were collected from these sections including sedimentology, organic geochemistry, isotope, geochronology, XRF, mineralogy, ichnology, palaeontology, palynology and digital outcrop data.
Historically, the Permian-Triassic boundary exposed today in Svalbard (and at various places across the High Arctic regions) was placed at the very prominent and abrupt facies change occurring between the siliceous mudstones or spiculites of the Kapp Starostin Formation, and the overlying soft, non-siliceous mudstones and siltstones of the Vardebukta and Vikinghøgda formations. The abruptness of this facies change, which also marks the demise of sponges, led to the belief that it represented a hiatus or a gap of several million years, with the uppermost Permian strata missing from the sedimentary record, while the mudstones of the Vardebukta and Vikinghøgda formations were definitely of Lower Triassic age, based on ammonoid biostratigraphy.
Hindeodus parvus, the conodont that defines the base of the Triassic, was for the first time identified in Svalbard a few meters above the lithostratigraphic boundary, which is therefore of Upper Permian age. Additionally, our new data show that sedimentation was continuous across this lithostratigraphic boundary. This transition from the Kapp Starostin Formation to the Vardebukta and Vikinghøgda formations was accompanied by a major reorganisation/inversion of the basin(s), but its exact nature remains puzzling.
Further, all measured sections record the EPME, which is associated with a 6-8 ‰ δ13CVPDB negative excursion, and measured between the lithostratigraphic and the Permian-Triassic boundaries. These negative isotopic excursions are found in close vicinity to several tephra layers that have been precisely dated at 252.13 ± 0.62 Ma, strongly suggesting a connection to the Siberian Traps LIP event. The mass extinction is also confirmed by the very rapid decreasing of trace fossil abundance and diversity, as anoxia spread across the water from proximal and shallow water to deeper settings. Geochemical and ichnological data indicate the occurrence of several anoxic pulses, intersected by very brief episodes of improved oxygenation levels. It took ca. 145 Kyr for life to recover after the extinction event, based on sedimentation rate calculations. Data also suggest that a shift towards more arid climatic conditions and increased eutrophication on land accompanied the EPME.
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Park, Juni; Stein, Holly J.; Hannah, Judith L.; Georgiev, Svetoslav; Yang, Gang & Hammer, Øyvind
[Vis alle 7 forfattere av denne artikkelen]
(2021).
Re-Os geochronology of black shale from Central Spitsbergen, Svalbard: a stepping stone toward establishing the age of the J/K boundary. .
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Stage boundaries are determined by integrating bio-, magneto-, and chrono-stratigraphic units. Numerical ages of stage boundaries ideally should be constrained or verified by reliable radiometric ages of sedimentary strata – a challenging task in the absence of ash layers suitable for U-Pb zircon dating. For example, the numerical age of the Jurassic – Cretaceous (J/K) boundary is still uncertain. Recent efforts provided some ammonite biostratigraphy across the J/K boundary in the Slottsmøya Member of the Agardhfjellet Formation on Spitsbergen. However, the age and duration of the uppermost Jurassic (Volgiann stage) and the lowermost Cretaceous (Ryazanian stage) in the Boreal realm remain loosely defined. Our study adds new radiometric ages for this controversial stage boundary and presents geochemical data to evaluate paleoenvironmental settings. Three black shale intervals from two drill cores (DH2 and DH5) located ~7 km apart in Central Spitsbergen provide three Re-Os ages. In DH2, shales from the Slottsmøya Member previously provided conflicting biostratigraphic results (Volgian toRyazanian)[1]. An isochron derived from samples at 497m depth yields an imprecise 146.8 ± 6.8 Ma age, suggesting deposition in the Upper Volgian rather th precludes confirmation. Large uncertainties near the J/K
boundary are typical for this region[2, 3]. Two Re-Os isochron ages from the Oppdalen Member (DH2 at 724 and DH5 at 658 m) yield similar ages of 157.6 ± 3.3 Ma and 157.9 ± 2.9 Ma, respectively. These ages are close to the GTS Oxfordian – Kimmeridgian stage boundary and, even within their uncertainties, suggest Oxfordian – Kimmeridgian deposition. The agreement between these correlative intervals in the two cores[4] lends credence to the accuracy of the Re-Os age.
Biostratigraphic data, however, suggest a somewhat older age. Seafloor erosion, reworking and redeposition, could create this discrepancy between geochronologic and biostratigraphic age determinations. Given that biostratigraphy between the Boreal and Tethyan realms is poorly correlated, the radiometric ages provided by this study could be a stepping stone toward better
connecting the Boreal with the Tethyan realm. But
further work, on all fronts, is needed.
Acknowledgements. Thanks to the UNIS CO2 LAB for access to the drill cores. HS acknowledges the supportof ACS-PRF award # 59965-ND2.
References:
[1] Koevoets, M.J., Hammer, Ø. & Little, C.T.S. (2019). Norwegian Journal of Geology 99, 1-24.
[2] Georgiev, S.V., Stein, H.J., Hannah, J.L., Xu, G.,Bingen, B., & Weiss, H.M. (2017).
EPSL, 461, 151-162.
[3] Markey, R., Stein, H.J., Hannah, J.L., Georgiev,.V., Pedersen, J.H., & Dons, C.E.(2017). Palaeogeography, Palaeoclimatology, Palaeoecology, 466, 209-220.
[4] Koevoets, M.J., Abay, T.B., Hammer, Ø., & Olaussen, S. (2016). Palaeogeography,
Palaeoclimatology, Palaeoecology, 449, 266-274
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Engelschiøn, Victoria Sjøholt; Wesenlund, Fredrik; Hurum, Jørn Harald; Hammer, Øyvind & Mørk, Atle
(2020).
East-west depositional trends and fossil preservation in the Middle Triassic Botneheia Fm. on Svalbard.
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Hammer, Øyvind & Jørgensen, Marte Holten
(2020).
Planter i røntgen.
Biolog.
ISSN 0801-0722.
2,
s. 25–28.
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Engelschiøn, Victoria Sjøholt; Hammer, Øyvind; Hurum, Jørn Harald; Bernhardsen, Sofie; Wesenlund, Fredrik & Roberts, Aubrey Jane
[Vis alle 7 forfattere av denne artikkelen]
(2020).
Large-scale lateral trends in palaeoenvironment and oxygenation in the Middle Triassic Botneheia Fm. on Svalbard.
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Hurum, Jørn Harald; Delsett, Lene Liebe; Hammer, Øyvind & Nakrem, Hans Arne
(2020).
15 years with the Spitsbergen Mesozoic Research Group.
NGF Abstracts and Proceedings of the Geological Society of Norway.
1,
s. 98–98.
Vis sammendrag
15 years with the Spitsbergen Mesozoic Research Group
Hurum, J. H.*, Delsett, L.L., Hammer, Ø. & Nakrem, H.A.
Natural History Museum, University of Oslo, Norway.
*Email: j.h.hurum@nhm.uio.no
When dinosaurs ruled on land the apex predators in the ocean were marine reptiles. From the Arctic archipelago of Svalbard, the Spitsbergen Mesozoic Research Group has excavated numerous well preserved marine reptile skeletons in order to understand the biology of these animals and the environment they lived in. The work of twelve field seasons since 2004 has made this one of the largest and most productive paleontological research projects in the high Arctic world-wide. The initial eight seasons focused on one of the richest occurrences of Late Jurassic—earliest Cretaceous (c. 150–139 Ma) marine reptiles in the world, and nearly sixty specimens have been collected, together with a diverse assemblage of invertebrates. The last four seasons were spent investigating events further back in time, as Spitsbergen preserves the remains from some of the first marine reptile radiations in the wake of the most devastating extinction in the history of the Earth, at the Permian–Triassic boundary (c. 252 Ma). The international research group published their first scientific results in 2012, followed by a steady stream of publications in the years since. Collectively, it has contributed significantly to the understanding of marine ecosystems at the Jurassic–Cretaceous boundary and is starting to yield results about life’s recovery in the first millions of years after the Permian–Triassic extinction. Outreach has been a major part of the project from the very beginning, both because it is important to share these scientific results with the public, but also because it attracts funding. Alternative financial support and a lot of determination have been crucial components for the success of this long term research project. This has been made possible through cooperation with a local tourist agency and the petroleum industry, grants from the National Geographic Society, income from public lectures and personal sponsors.
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Mattsson, Tobias; Burchardt, Steffi; Palma, Octavio; Galland, Olivier; Almqvist, Bjarne S.G. & Hammer, Øyvind
[Vis alle 9 forfattere av denne artikkelen]
(2019).
Magmatic fabrics related to different growth stages of the Cerro Bayo Cryptodome.
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Engelschiøn, Victoria Sjøholt; Bernhardsen, Sofie; Wesenlund, Fredrik; Hurum, Jørn Harald; Hammer, Øyvind & Roberts, Aubrey Jane
[Vis alle 9 forfattere av denne artikkelen]
(2019).
Mass death by anoxia - or an exceptional preservation interval?
The Middle Triassic bivalve beds of Svalbard.
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Engelschiøn, Victoria Sjøholt; Hammer, Øyvind; Hurum, Jørn Harald; Wesenlund, Fredrik; Bernhardsen, Sofie & Mørk, Atle
(2019).
East-west trends in palaeoenvironment and oxygenation in the Middle Triassic Botneheia Fm., Svalbard.
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Engelschiøn, Victoria Sjøholt; Bernhardsen, Sofie; Wesenlund, Fredrik; Hurum, Jørn Harald; Hammer, Øyvind & Mørk, Atle
(2019).
Anoxia and mass death – a high-resolution biofacies study of the Ladinian (Middle Triassic) Blanknuten Mb., Botneheia Fm. on Edgeøya.
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Engelschiøn, Victoria Sjøholt; Bernhardsen, Sofie; Wesenlund, Fredrik; Hammer, Øyvind; Hurum, Jørn Harald & Mørk, Atle
(2019).
The geobiosphere of the Middle Triassic of Svalbard- linking biofacies to geochemistry.
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Engelschiøn, Victoria Sjøholt; Bernhardsen, Sofie; Wesenlund, Fredrik; Hammer, Øyvind; Hurum, Jørn Harald & Mørk, Atle
(2019).
"Palaeontology of the Middle Triassic dysoxic succession of the Botneheia Fm., Svalbard".
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Hurum, Jørn Harald; Nakrem, Hans Arne; Hammer, Øyvind & Delsett, Lene Liebe
(2019).
Gravplass i verdensformat.
Geo.
ISSN 1500-8371.
22(3),
s. 12–18.
Vis sammendrag
Utgravninger på Svalbard gjennom 15 år har gitt overraskende og sensasjonelle oppdagelser om livets
utvikling både i tidlig trias og på overgangen mellom sein jura og tidlig kritt
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Jones, Morgan Thomas; Hammer, Øyvind; Bucher, Hugo; Schneebeli-Hermann, Elke; Mather, Tamsin & Svensen, Henrik
[Vis alle 7 forfattere av denne artikkelen]
(2019).
Are Mercury Anomalies a Reliable Proxy for LIP Volcanism? Examples from the End-Permian and Early Triassic.
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Olaussen, Snorre; Senger, Kim; Birchall, Thomas; Braathen, Alvar; Grundvåg, Sten-Andreas & Hammer, Øyvind
[Vis alle 13 forfattere av denne artikkelen]
(2018).
The Longyearbyen CO2 lab project: lessons learned from a decade of characterizing an unconventional reservoir-caprock system.
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Stokke, Ella Wulfsberg; Jones, Morgan Thomas; Hammer, Øyvind & Svensen, Henrik
(2018).
Geochemistry of Paleocene- Eocene sediments on Fur,
Denmark: Linking volcanism and climatic changes.
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Stokke, Ella Wulfsberg; Whiteside, Jessica H.; Svensen, Henrik; Hammer, Øyvind & Jones, Morgan Thomas
(2018).
Linking warming, environmental changes, and volcanic ash falls from onset to recovery of the PETM: investigations from Fur, Denmark.
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Stokke, Ella Wulfsberg; Jones, Morgan Thomas; Hammer, Øyvind & Svensen, Henrik
(2018).
Geochemical variations during the PETM and later Eocene
hyperthermals: investigating a new drill core from Fur, Denmark.
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Mazzini, Adriano; Svensen, Henrik; Forsberg, Carl Fredrik; Linge, Henriette; Lauritzen, Stein-Erik & Haflidason, Haflidi
[Vis alle 9 forfattere av denne artikkelen]
(2017).
A Climatic Trigger for the Giant Troll Pockmark Field in the Northern North Sea.
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Pockmarks are seafloor craters usually formed during methane release on continental margins. However, the mechanisms behind their formation and dynamics remain elusive. Here we report detailed investigations on one of the World’s largest pockmark fields located in the Troll region in the northern North Sea. Seafloor investigations show that >7000 pockmarks are present in a ~600 km2 area. A similar density of pockmarks is likely present over a 15,000 km2 region outside our study area. Based on extensive monitoring, coring, geophysical and geochemical analyses, no indications of active gas seepage were found. Still, geochemical data from carbonate blocks collected from these pockmarks indicate a methanogenic origin linked to gas hydrate dissociation and past fluid venting at the seafloor. We have dated the carbonates using the U-Th method in order to constrain the pockmark formation. The carbonates gave an isochron age of 9.59 ± 1.38 ka BP, i.e. belonging to the initial Holocene. Moreover, radiocarbon dating of microfossils in the sediments inside the pockmarks are consistent with the ages derived from the carbonates. Based on pressure and temperature modelling, we show that the last deglaciation could have triggered dissociation of gas hydrates present in the region of the northern part of the Norwegian Channel, causing degassing of 0.26 MtCH4/km2 at the seafloor. Our results stress the importance of external climatic forcing of the dynamics of the seafloor, and the role of the rapid warming following the Younger Dryas in pacing the marine gas hydrate reservoir.
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Collignon, Marine; Hammer, Øyvind; Fallahi, Mohammad Javad; Lupi, Matteo; Schmid, Daniel Walter & Husein, Alwi
[Vis alle 8 forfattere av denne artikkelen]
(2017).
Linking the Lusi mud eruption dynamics with regional and global seismic activity: a statistical analysis.
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Delsett, Lene Liebe; Koevoets, Maayke Jacqueline; Hammer, Øyvind; Novis, Linn Kristin; Roberts, Aubrey Jane & Druckenmiller, Patrick Scott
[Vis alle 7 forfattere av denne artikkelen]
(2017).
Marine reptiles from death to discovery.
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Delsett, Lene Liebe; Koevoets, Maayke Jacqueline; Hammer, Øyvind; Novis, Linn Kristin; Roberts, Aubrey Jane & Druckenmiller, Patrick Scott
[Vis alle 7 forfattere av denne artikkelen]
(2017).
A model for marine reptile taphonomy in the Late Jurassic Slottsmøya Member Lagerstätte.
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Planke, Sverre; Zuchuat, Valentin; Svensen, Henrik; Hammer, Øyvind; Braathen, Alvar & Silkoset, Petter
[Vis alle 27 forfattere av denne artikkelen]
(2016).
Coring and High-Resolution Imaging of the Permian-Triassic Boundary in Deltadalen, Svalbard.
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Delsett, Lene Liebe; Novis, Linn Kristin; Roberts, Aubrey Jane; Koevoets, Maayke Jacqueline; Hammer, Øyvind & Druckenmiller, Patrick Scott
[Vis alle 7 forfattere av denne artikkelen]
(2015).
Ichthyosaurs from the Late Jurassic - Early Cretaceous on Spitsbergen.
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Piazza, Veronica; Hammer, Øyvind & Nakrem, Hans Arne
(2015).
Late Smithian (Early Triassic) ammonoids from the uppermost Lusitaniadalen Member (Vikinghøgda Formation), Svalbard.
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Hurum, Jørn Harald; Druckenmiller, Patrick Scott; Hammer, Øyvind; Nakrem, Hans Arne & Olaussen, Snorre
(2015).
New dinosaur tracks at Kvalvågen, Svalbard.
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Hurum, Jørn Harald; Hammer, Øyvind & Nakrem, Hans Arne
(2015).
The vertebrate faunal recovery in Svalbard after the P-T extinction (Poster).
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Piazza, Veronica; Hammer, Øyvind & Nakrem, Hans Arne
(2015).
Late Smithian (Early Triassic) ammonoid biostratigraphy of Spitsbergen.
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Svensen, Henrik; Hammer, Øyvind & Corfu, Fernando
(2015).
Corrigendum to "Astronomically forced cyclicity in the Upper Ordovician and U-Pb ages of interlayered tephra, Oslo Region, Norway" [Palaeogeogr. Palaeoclimatol. Palaeoecol.: 418C, (2015), 150-159], doi:10.1016/j.palaeo.2014.11.001mm.
Palaeogeography, Palaeoclimatology, Palaeoecology.
ISSN 0031-0182.
423,
s. 149–149.
doi:
10.1016/j.palaeo.2015.02.001.
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Hurum, Jørn Harald; Nakrem, Hans Arne & Hammer, Øyvind
(2014).
Resultater over all forventning.
[Avis].
Svalbardposten.
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Hurum, Jørn Harald; Nakrem, Hans Arne & Hammer, Øyvind
(2014).
I kjempeøglenes fotspor.
[Avis].
Svalbardposten.
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Hammer, Øyvind
(2014).
Don't quote me on this.
I Cullum, Alex (Red.),
52 things you should know about palaeontology.
Agile Libre.
ISSN 9780987959447.
s. 48–49.
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Hammer, Øyvind; Hryniewicz, Krzysztof; Nakrem, Hans Arne & Little, Crispin T.S.
(2014).
Hydrocarbon Seepage during the Boreal Base Cretaceous Hot Shale Event.
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Olaussen, Snorre; Abay, Tesfamariam Berhane; Karlsen, Dag Arild; Hammer, Øyvind & Pedersen, Jon Halvard
(2014).
Novel Results on Migrated Oil in several Svalbard out-crop samples. What does this tell us about the Petroleum Systems responsible for the Migrated Oils in these samples.
