Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard
Two unconformities have been found in central Nordaustlandet. New mapping has located a major unconformity at the base of the Neoproterozoic Murchisonfjorden Supergroup, with quartzites and basal conglomerates of the Djevleflota Formation unconformably overlying dark phyllites of the Helvetesflya Fo...
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Norwegian Polar Institute
1996
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ftjpolarres:oai:journals.openacademia.net:article/1921 2023-05-15T15:38:58+02:00 Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard Gee, David G. Teben'kov, Alexander M. 1996-01-06 application/pdf https://polarresearch.net/index.php/polar/article/view/1921 https://doi.org/10.3402/polar.v15i1.6638 eng eng Norwegian Polar Institute https://polarresearch.net/index.php/polar/article/view/1921/5170 https://polarresearch.net/index.php/polar/article/view/1921 doi:10.3402/polar.v15i1.6638 Copyright (c) 2018 Polar Research Polar Research; Vol. 15 No. 1 (1996); 81-91 1751-8369 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 1996 ftjpolarres https://doi.org/10.3402/polar.v15i1.6638 2021-11-11T19:11:42Z Two unconformities have been found in central Nordaustlandet. New mapping has located a major unconformity at the base of the Neoproterozoic Murchisonfjorden Supergroup, with quartzites and basal conglomerates of the Djevleflota Formation unconformably overlying dark phyllites of the Helvetesflya Formation and metavolcanic rocks of the Svartrabbane Formation. A second unconformity separates the Helvetesflya from the Svartrabbane formations. These rocks were isoclinally folded, metamorphosed in lower greenschist facies, and, apparently, syntectonically intruded by Grenville-age granites, prior to uplift, erosion and Neoproterozoic deposition. Caledonian tectonothermal activity, as recorded in the Neoproterozoic strata, appears to vary very little across Svalbard's Eastern Terrane from Ny Friesland, in the west, to Murchisonfjorden in western Nordaustlandet and, via Wahlenbergfjorden, to the central Nordaustlandet area, described here. Upright folds with associated high angle, usually E-dipping cleavages, characterise the Caledonian deformation over an east-west distance of about 100 km. This evidence allows the possibility that the pre-Devonian basement, to the east of Nordaustlandet, beneath the northern Barents Sea (Barentsia), may be composed of Grenville-age complexes little influenced by Caledonian tectonothermal activity. Alternatively, Barentsia is dominated by Caledonian hinterland tectonics, with extensive middle Paleozoic tectonothermal reworking of a Precambrian basement. Article in Journal/Newspaper Barents Sea Nordaustlandet Ny Friesland Polar Research Svalbard Polar Research (E-Journal) Svalbard Barents Sea Nordaustlandet ENVELOPE(22.400,22.400,79.800,79.800) Ny Friesland ENVELOPE(16.847,16.847,79.498,79.498) Murchisonfjorden ENVELOPE(18.429,18.429,79.986,79.986) Wahlenbergfjorden ENVELOPE(20.593,20.593,79.721,79.721) Helvetesflya ENVELOPE(22.250,22.250,79.967,79.967) Polar Research 15 1 81 91 |
institution |
Open Polar |
collection |
Polar Research (E-Journal) |
op_collection_id |
ftjpolarres |
language |
English |
description |
Two unconformities have been found in central Nordaustlandet. New mapping has located a major unconformity at the base of the Neoproterozoic Murchisonfjorden Supergroup, with quartzites and basal conglomerates of the Djevleflota Formation unconformably overlying dark phyllites of the Helvetesflya Formation and metavolcanic rocks of the Svartrabbane Formation. A second unconformity separates the Helvetesflya from the Svartrabbane formations. These rocks were isoclinally folded, metamorphosed in lower greenschist facies, and, apparently, syntectonically intruded by Grenville-age granites, prior to uplift, erosion and Neoproterozoic deposition. Caledonian tectonothermal activity, as recorded in the Neoproterozoic strata, appears to vary very little across Svalbard's Eastern Terrane from Ny Friesland, in the west, to Murchisonfjorden in western Nordaustlandet and, via Wahlenbergfjorden, to the central Nordaustlandet area, described here. Upright folds with associated high angle, usually E-dipping cleavages, characterise the Caledonian deformation over an east-west distance of about 100 km. This evidence allows the possibility that the pre-Devonian basement, to the east of Nordaustlandet, beneath the northern Barents Sea (Barentsia), may be composed of Grenville-age complexes little influenced by Caledonian tectonothermal activity. Alternatively, Barentsia is dominated by Caledonian hinterland tectonics, with extensive middle Paleozoic tectonothermal reworking of a Precambrian basement. |
format |
Article in Journal/Newspaper |
author |
Gee, David G. Teben'kov, Alexander M. |
spellingShingle |
Gee, David G. Teben'kov, Alexander M. Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
author_facet |
Gee, David G. Teben'kov, Alexander M. |
author_sort |
Gee, David G. |
title |
Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
title_short |
Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
title_full |
Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
title_fullStr |
Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
title_full_unstemmed |
Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard |
title_sort |
two major unconformities beneath the neoproterozoic murchisonfjorden supergroup in the caledonides of central nordaustlandet, svalbard |
publisher |
Norwegian Polar Institute |
publishDate |
1996 |
url |
https://polarresearch.net/index.php/polar/article/view/1921 https://doi.org/10.3402/polar.v15i1.6638 |
long_lat |
ENVELOPE(22.400,22.400,79.800,79.800) ENVELOPE(16.847,16.847,79.498,79.498) ENVELOPE(18.429,18.429,79.986,79.986) ENVELOPE(20.593,20.593,79.721,79.721) ENVELOPE(22.250,22.250,79.967,79.967) |
geographic |
Svalbard Barents Sea Nordaustlandet Ny Friesland Murchisonfjorden Wahlenbergfjorden Helvetesflya |
geographic_facet |
Svalbard Barents Sea Nordaustlandet Ny Friesland Murchisonfjorden Wahlenbergfjorden Helvetesflya |
genre |
Barents Sea Nordaustlandet Ny Friesland Polar Research Svalbard |
genre_facet |
Barents Sea Nordaustlandet Ny Friesland Polar Research Svalbard |
op_source |
Polar Research; Vol. 15 No. 1 (1996); 81-91 1751-8369 |
op_relation |
https://polarresearch.net/index.php/polar/article/view/1921/5170 https://polarresearch.net/index.php/polar/article/view/1921 doi:10.3402/polar.v15i1.6638 |
op_rights |
Copyright (c) 2018 Polar Research |
op_doi |
https://doi.org/10.3402/polar.v15i1.6638 |
container_title |
Polar Research |
container_volume |
15 |
container_issue |
1 |
container_start_page |
81 |
op_container_end_page |
91 |
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1766370405605441536 |