Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard
The Forlandsundet Graben, situated along the NE Atlantic continental margin in the western Svalbard archipelago in Arctic Norway, represents a unique opportunity to study a basin that evolved along an obliquely rifted margin. It is bound by N–S-trending fault zones that cross-cut the structures of t...
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Geological Society of Norway
2021
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Online Access: | https://hdl.handle.net/11250/3043391 https://doi.org/10.17850/njg100-4-4 |
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ftntnutrondheimi:oai:ntnuopen.ntnu.no:11250/3043391 2023-05-15T15:13:03+02:00 Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard Schaaf, Niklas W. Osmundsen, Per Terje van der Lelij, Roelant Schönenberger, Jasmin Lenz, Olaf K. Redfield, Thomas Fitzmaurice Senger, Kim 2021 application/pdf https://hdl.handle.net/11250/3043391 https://doi.org/10.17850/njg100-4-4 eng eng Geological Society of Norway Norwegian Journal of Geology. 2021, 100 (4), . urn:issn:2387-5844 https://hdl.handle.net/11250/3043391 https://doi.org/10.17850/njg100-4-4 cristin:2012252 39 100 Norwegian Journal of Geology 4 Peer reviewed Journal article 2021 ftntnutrondheimi https://doi.org/10.17850/njg100-4-4 2023-01-18T23:43:08Z The Forlandsundet Graben, situated along the NE Atlantic continental margin in the western Svalbard archipelago in Arctic Norway, represents a unique opportunity to study a basin that evolved along an obliquely rifted margin. It is bound by N–S-trending fault zones that cross-cut the structures of the Eocene West Spitsbergen-fold-and-thrust-belt. The basin fill comprises coarse continent-derived siliciclastics and finer-grained marine deposits. The Forlandsundet Graben is a keystone to understand the evolution of the west Svalbard margin from a transpressional fold-andthrust-belt to a sharply tapered transtensional margin during the Paleogene. We report data collected during three field seasons at the eastern basin margin, including outcrop descriptions, ~500 structural measurements, ~370 m of sedimentary logs, more than 100 paleocurrent indicators and results from palynology, K–Ar dating and apatite fission track thermochronology. Our results suggest that the basement units along the eastern basin boundary experienced reverse faulting and illite growth in a fault gouge at 53.5 ± 1.0 Ma likely related to the Eurekan orogeny. This transpressional phase was followed by NW–SE transtensional rifting which initiated the oblique normal faults that constitute the present eastern basin boundary. In this setting, the sedimentary units on Sarsøyra were deposited. The older Sarsbukta conglomerate comprises interfingering alluvial-fan and fluvial deposits. It was affected by transtensional folding and faulting. The rocks of the younger Sarstangen conglomerate record basin-floor and fan-delta sedimentation and thus transition to marine deposition along a major intrabasinal normal or oblique fault. Palynostratigraphic analyses suggest an Early to Middle Oligocene age for the Sarstangen conglomerate. Our findings further highlight a maturity discrepancy between the sedimentary deposits along the eastern and western basin boundaries. On this basis, we discuss possible basin models, including the evolution of the Forlandsundet ... Article in Journal/Newspaper Arctic Forlandsundet Svalbard Svalbard margin Spitsbergen NTNU Open Archive (Norwegian University of Science and Technology) Arctic Forlandsundet ENVELOPE(11.984,11.984,78.510,78.510) Norway Sarsbukta ENVELOPE(11.647,11.647,78.719,78.719) Sarstangen ENVELOPE(11.552,11.552,78.724,78.724) Sarsøyra ENVELOPE(11.806,11.806,78.760,78.760) Svalbard Svalbard Archipelago Western Basin Norwegian Journal of Geology |
institution |
Open Polar |
collection |
NTNU Open Archive (Norwegian University of Science and Technology) |
op_collection_id |
ftntnutrondheimi |
language |
English |
description |
The Forlandsundet Graben, situated along the NE Atlantic continental margin in the western Svalbard archipelago in Arctic Norway, represents a unique opportunity to study a basin that evolved along an obliquely rifted margin. It is bound by N–S-trending fault zones that cross-cut the structures of the Eocene West Spitsbergen-fold-and-thrust-belt. The basin fill comprises coarse continent-derived siliciclastics and finer-grained marine deposits. The Forlandsundet Graben is a keystone to understand the evolution of the west Svalbard margin from a transpressional fold-andthrust-belt to a sharply tapered transtensional margin during the Paleogene. We report data collected during three field seasons at the eastern basin margin, including outcrop descriptions, ~500 structural measurements, ~370 m of sedimentary logs, more than 100 paleocurrent indicators and results from palynology, K–Ar dating and apatite fission track thermochronology. Our results suggest that the basement units along the eastern basin boundary experienced reverse faulting and illite growth in a fault gouge at 53.5 ± 1.0 Ma likely related to the Eurekan orogeny. This transpressional phase was followed by NW–SE transtensional rifting which initiated the oblique normal faults that constitute the present eastern basin boundary. In this setting, the sedimentary units on Sarsøyra were deposited. The older Sarsbukta conglomerate comprises interfingering alluvial-fan and fluvial deposits. It was affected by transtensional folding and faulting. The rocks of the younger Sarstangen conglomerate record basin-floor and fan-delta sedimentation and thus transition to marine deposition along a major intrabasinal normal or oblique fault. Palynostratigraphic analyses suggest an Early to Middle Oligocene age for the Sarstangen conglomerate. Our findings further highlight a maturity discrepancy between the sedimentary deposits along the eastern and western basin boundaries. On this basis, we discuss possible basin models, including the evolution of the Forlandsundet ... |
format |
Article in Journal/Newspaper |
author |
Schaaf, Niklas W. Osmundsen, Per Terje van der Lelij, Roelant Schönenberger, Jasmin Lenz, Olaf K. Redfield, Thomas Fitzmaurice Senger, Kim |
spellingShingle |
Schaaf, Niklas W. Osmundsen, Per Terje van der Lelij, Roelant Schönenberger, Jasmin Lenz, Olaf K. Redfield, Thomas Fitzmaurice Senger, Kim Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
author_facet |
Schaaf, Niklas W. Osmundsen, Per Terje van der Lelij, Roelant Schönenberger, Jasmin Lenz, Olaf K. Redfield, Thomas Fitzmaurice Senger, Kim |
author_sort |
Schaaf, Niklas W. |
title |
Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
title_short |
Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
title_full |
Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
title_fullStr |
Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
title_full_unstemmed |
Tectono-sedimentary evolution of the eastern Forlandsundet Graben, Svalbard |
title_sort |
tectono-sedimentary evolution of the eastern forlandsundet graben, svalbard |
publisher |
Geological Society of Norway |
publishDate |
2021 |
url |
https://hdl.handle.net/11250/3043391 https://doi.org/10.17850/njg100-4-4 |
long_lat |
ENVELOPE(11.984,11.984,78.510,78.510) ENVELOPE(11.647,11.647,78.719,78.719) ENVELOPE(11.552,11.552,78.724,78.724) ENVELOPE(11.806,11.806,78.760,78.760) |
geographic |
Arctic Forlandsundet Norway Sarsbukta Sarstangen Sarsøyra Svalbard Svalbard Archipelago Western Basin |
geographic_facet |
Arctic Forlandsundet Norway Sarsbukta Sarstangen Sarsøyra Svalbard Svalbard Archipelago Western Basin |
genre |
Arctic Forlandsundet Svalbard Svalbard margin Spitsbergen |
genre_facet |
Arctic Forlandsundet Svalbard Svalbard margin Spitsbergen |
op_source |
39 100 Norwegian Journal of Geology 4 |
op_relation |
Norwegian Journal of Geology. 2021, 100 (4), . urn:issn:2387-5844 https://hdl.handle.net/11250/3043391 https://doi.org/10.17850/njg100-4-4 cristin:2012252 |
op_doi |
https://doi.org/10.17850/njg100-4-4 |
container_title |
Norwegian Journal of Geology |
_version_ |
1766343659593138176 |