The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution
The geological evolution of the southwest Rockall Plateau in the area of Edoras Bank has been clarified using seismic reflection, gravity and magnetic data. Four principal reflectors are observed within the Tertiary sedimentary sequence: I, Late Miocene; 11, latest Early Miocene; 111, Late Eocene; I...
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ftsouthampton:oai:eprints.soton.ac.uk:363783 2023-07-30T04:03:49+02:00 The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution Bull, Jonathan M. Masson, Douglas G. 1996 https://eprints.soton.ac.uk/363783/ English eng Bull, Jonathan M. and Masson, Douglas G. (1996) The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution. Journal of the Geological Society, 153 (4), 601-612. (doi:10.1144/gsjgs.153.4.0601 <http://dx.doi.org/10.1144/gsjgs.153.4.0601>). Article PeerReviewed 1996 ftsouthampton https://doi.org/10.1144/gsjgs.153.4.0601 2023-07-09T21:52:27Z The geological evolution of the southwest Rockall Plateau in the area of Edoras Bank has been clarified using seismic reflection, gravity and magnetic data. Four principal reflectors are observed within the Tertiary sedimentary sequence: I, Late Miocene; 11, latest Early Miocene; 111, Late Eocene; IV, earliest Eocene. A period of pronounced sediment drift accumulation marks the interval 1-11. Reflector 111, the top of a sediment wedge prograding southward from Edoras Bank, marks a change from terrigenous to pelagic sedimentation that is probably related to subsidence of the Rockall Plateau following the separation of Greenland from Eurasia in the earliest Eocene. Reflector IV marks the top of a wedge-shaped seismically transparent layer that also thins southward away from Edoras Bank. On the basis of its seismic attributes and magnetic signature, this layer is interpreted as a volcanic sheet, formed as part of the North Atlantic Tertiary Volcanic Province during rifting of Greenland from Eurasia. The recognition of voluminous volcanic rocks south of Edoras Bank extends the known area of the Tertiary volcanic province several hundred kilometres to the south. Gravity anomaly modelling and continental reconstructions suggest that the region south of Edoras Bank is underlain by thinned continental crust. A four stage geological evolution for this region is indicated. (i) Initial rifting associated with the separation of Labrador from Greenland in the late Cretaceous is characterized by enhanced crustal thinning and subsidence in the region of a rift triple junction. (ii) Passive subsidence and accumulation of late Cretaceous and earliest Tertiary sediments followed the initiation of seafloor spreading in the Labrador Sea. (iii) Blanketing of the area by Palaeocene volcanic rocks masked pre-existing magnetic lineations, providing an explanation for some of the problems in earlier interpretations based mainly on magnetic data. (iv) Post-volcanic sedimentation, continuing to the present day. Article in Journal/Newspaper Greenland Labrador Sea North Atlantic University of Southampton: e-Prints Soton Edoras Bank ENVELOPE(-22.167,-22.167,56.000,56.000) Greenland Rockall Plateau ENVELOPE(-18.833,-18.833,56.333,56.333) Journal of the Geological Society 153 4 601 612 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
The geological evolution of the southwest Rockall Plateau in the area of Edoras Bank has been clarified using seismic reflection, gravity and magnetic data. Four principal reflectors are observed within the Tertiary sedimentary sequence: I, Late Miocene; 11, latest Early Miocene; 111, Late Eocene; IV, earliest Eocene. A period of pronounced sediment drift accumulation marks the interval 1-11. Reflector 111, the top of a sediment wedge prograding southward from Edoras Bank, marks a change from terrigenous to pelagic sedimentation that is probably related to subsidence of the Rockall Plateau following the separation of Greenland from Eurasia in the earliest Eocene. Reflector IV marks the top of a wedge-shaped seismically transparent layer that also thins southward away from Edoras Bank. On the basis of its seismic attributes and magnetic signature, this layer is interpreted as a volcanic sheet, formed as part of the North Atlantic Tertiary Volcanic Province during rifting of Greenland from Eurasia. The recognition of voluminous volcanic rocks south of Edoras Bank extends the known area of the Tertiary volcanic province several hundred kilometres to the south. Gravity anomaly modelling and continental reconstructions suggest that the region south of Edoras Bank is underlain by thinned continental crust. A four stage geological evolution for this region is indicated. (i) Initial rifting associated with the separation of Labrador from Greenland in the late Cretaceous is characterized by enhanced crustal thinning and subsidence in the region of a rift triple junction. (ii) Passive subsidence and accumulation of late Cretaceous and earliest Tertiary sediments followed the initiation of seafloor spreading in the Labrador Sea. (iii) Blanketing of the area by Palaeocene volcanic rocks masked pre-existing magnetic lineations, providing an explanation for some of the problems in earlier interpretations based mainly on magnetic data. (iv) Post-volcanic sedimentation, continuing to the present day. |
format |
Article in Journal/Newspaper |
author |
Bull, Jonathan M. Masson, Douglas G. |
spellingShingle |
Bull, Jonathan M. Masson, Douglas G. The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
author_facet |
Bull, Jonathan M. Masson, Douglas G. |
author_sort |
Bull, Jonathan M. |
title |
The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
title_short |
The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
title_full |
The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
title_fullStr |
The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
title_full_unstemmed |
The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution |
title_sort |
southern margin of the rockall plateau: stratigraphy, tertiary volcanism and plate tectonic evolution |
publishDate |
1996 |
url |
https://eprints.soton.ac.uk/363783/ |
long_lat |
ENVELOPE(-22.167,-22.167,56.000,56.000) ENVELOPE(-18.833,-18.833,56.333,56.333) |
geographic |
Edoras Bank Greenland Rockall Plateau |
geographic_facet |
Edoras Bank Greenland Rockall Plateau |
genre |
Greenland Labrador Sea North Atlantic |
genre_facet |
Greenland Labrador Sea North Atlantic |
op_relation |
Bull, Jonathan M. and Masson, Douglas G. (1996) The southern margin of the Rockall Plateau: stratigraphy, Tertiary volcanism and plate tectonic evolution. Journal of the Geological Society, 153 (4), 601-612. (doi:10.1144/gsjgs.153.4.0601 <http://dx.doi.org/10.1144/gsjgs.153.4.0601>). |
op_doi |
https://doi.org/10.1144/gsjgs.153.4.0601 |
container_title |
Journal of the Geological Society |
container_volume |
153 |
container_issue |
4 |
container_start_page |
601 |
op_container_end_page |
612 |
_version_ |
1772814932907130880 |