Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup
In 1999 new seismic refraction data were collected off northwestern Svalbard and the adjacent Yermak Plateau. A 260 km long profile provides detailed velocity information for the northeastern edge of the Eurasian Continent and the adjacent Yermak Plateau. North of Forlandsundet Graben the depth of t...
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fthighwire:oai:open-archive.highwire.org:gji:152/1/139 2023-05-15T16:00:07+02:00 Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup Ritzmann, Oliver Jokat, Wilfried 2003-01-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/152/1/139 https://doi.org/10.1046/j.1365-246X.2003.01836.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/152/1/139 http://dx.doi.org/10.1046/j.1365-246X.2003.01836.x Copyright (C) 2003, Oxford University Press Research Papers TEXT 2003 fthighwire https://doi.org/10.1046/j.1365-246X.2003.01836.x 2013-05-26T22:52:16Z In 1999 new seismic refraction data were collected off northwestern Svalbard and the adjacent Yermak Plateau. A 260 km long profile provides detailed velocity information for the northeastern edge of the Eurasian Continent and the adjacent Yermak Plateau. North of Forlandsundet Graben the depth of the Moho varies between 23 and 28 km, and remains at this depth to the northern edge of the profile at 81°N. The crustal lithology off western Svalbard can be related to the basement province west of the Raudfjorden Fault Zone. Off the northern shoreline of Svalbard the structure of the Tertiary Danskøya Basin is mapped. Below this, a Late Silurian/Early Devonian basin, with seismic velocities between 5.1 and 5.8 km s−1 and a thickness of up to 8 km is present. A Palaeozoic sequence of up to 6 km thickness is expected below the Tertiary cover north of the Danskøya Basin. An earlier suggestion, that Oligocene rift processes affected the southern Yermak Plateau, is confirmed. A detachment structure is situated below the Palaeozoic Basin below Danskøya Basin, which is probably a consequence of simple shear tectonics. The middle crust exhibits low seismic velocities above the detachment fault. The lowermost crust beneath is slightly contaminated by mantle-derived melts, which is deduced by the slightly elevated velocities of the lowermost crust. These melts can be attributed to decompressive melting caused by modest uplift of the Moho during stretching. The velocity–depth model provides no evidence for large magmatic activity, which implies a non-volcanic rifted margin history. This leads to the assumption that the proposed Yermak Hotspot during the breakup of Svalbard from northern Greenland did not exist. Text Danskøya Forlandsundet Greenland Svalbard Yermak plateau HighWire Press (Stanford University) Svalbard Greenland Yermak Plateau ENVELOPE(5.000,5.000,81.250,81.250) Forlandsundet ENVELOPE(11.984,11.984,78.510,78.510) Danskøya ENVELOPE(10.933,10.933,79.700,79.700) Raudfjorden ENVELOPE(12.079,12.079,79.775,79.775) Geophysical Journal International 152 1 139 159 |
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Open Polar |
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HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Research Papers |
spellingShingle |
Research Papers Ritzmann, Oliver Jokat, Wilfried Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
topic_facet |
Research Papers |
description |
In 1999 new seismic refraction data were collected off northwestern Svalbard and the adjacent Yermak Plateau. A 260 km long profile provides detailed velocity information for the northeastern edge of the Eurasian Continent and the adjacent Yermak Plateau. North of Forlandsundet Graben the depth of the Moho varies between 23 and 28 km, and remains at this depth to the northern edge of the profile at 81°N. The crustal lithology off western Svalbard can be related to the basement province west of the Raudfjorden Fault Zone. Off the northern shoreline of Svalbard the structure of the Tertiary Danskøya Basin is mapped. Below this, a Late Silurian/Early Devonian basin, with seismic velocities between 5.1 and 5.8 km s−1 and a thickness of up to 8 km is present. A Palaeozoic sequence of up to 6 km thickness is expected below the Tertiary cover north of the Danskøya Basin. An earlier suggestion, that Oligocene rift processes affected the southern Yermak Plateau, is confirmed. A detachment structure is situated below the Palaeozoic Basin below Danskøya Basin, which is probably a consequence of simple shear tectonics. The middle crust exhibits low seismic velocities above the detachment fault. The lowermost crust beneath is slightly contaminated by mantle-derived melts, which is deduced by the slightly elevated velocities of the lowermost crust. These melts can be attributed to decompressive melting caused by modest uplift of the Moho during stretching. The velocity–depth model provides no evidence for large magmatic activity, which implies a non-volcanic rifted margin history. This leads to the assumption that the proposed Yermak Hotspot during the breakup of Svalbard from northern Greenland did not exist. |
format |
Text |
author |
Ritzmann, Oliver Jokat, Wilfried |
author_facet |
Ritzmann, Oliver Jokat, Wilfried |
author_sort |
Ritzmann, Oliver |
title |
Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
title_short |
Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
title_full |
Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
title_fullStr |
Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
title_full_unstemmed |
Crustal structure of northwestern Svalbard and the adjacent Yermak Plateau: evidence for Oligocene detachment tectonics and non-volcanic breakup |
title_sort |
crustal structure of northwestern svalbard and the adjacent yermak plateau: evidence for oligocene detachment tectonics and non-volcanic breakup |
publisher |
Oxford University Press |
publishDate |
2003 |
url |
http://gji.oxfordjournals.org/cgi/content/short/152/1/139 https://doi.org/10.1046/j.1365-246X.2003.01836.x |
long_lat |
ENVELOPE(5.000,5.000,81.250,81.250) ENVELOPE(11.984,11.984,78.510,78.510) ENVELOPE(10.933,10.933,79.700,79.700) ENVELOPE(12.079,12.079,79.775,79.775) |
geographic |
Svalbard Greenland Yermak Plateau Forlandsundet Danskøya Raudfjorden |
geographic_facet |
Svalbard Greenland Yermak Plateau Forlandsundet Danskøya Raudfjorden |
genre |
Danskøya Forlandsundet Greenland Svalbard Yermak plateau |
genre_facet |
Danskøya Forlandsundet Greenland Svalbard Yermak plateau |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/152/1/139 http://dx.doi.org/10.1046/j.1365-246X.2003.01836.x |
op_rights |
Copyright (C) 2003, Oxford University Press |
op_doi |
https://doi.org/10.1046/j.1365-246X.2003.01836.x |
container_title |
Geophysical Journal International |
container_volume |
152 |
container_issue |
1 |
container_start_page |
139 |
op_container_end_page |
159 |
_version_ |
1766395984159440896 |