The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves
Imaging challenges caused by highly attenuative flood basalt sequences have resulted in the understanding of volcanic rifted continental margins lagging behind that of non-volcanic rifted and convergent margins. Massive volcanism occurred during break-up at 70% of the passive margins bordering the A...
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ftunivauckland:oai:researchspace.auckland.ac.nz:2292/19108 2023-05-15T16:11:00+02:00 The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves Eccles, JD White, RS Christie, PAF 2011 http://hdl.handle.net/2292/19108 https://doi.org/10.1016/j.tecto.2010.02.001 English eng ELSEVIER SCIENCE BV Tectonophysics Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. Details obtained from http://www.sherpa.ac.uk/romeo/issn/0040-1951/ https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm Copyright: ELSEVIER SCIENCE BV http://purl.org/eprint/accessRights/RestrictedAccess http://dx.doi.org/10.1016/j.tecto.2010.02.001 Science & Technology Physical Sciences Geochemistry & Geophysics Volcanic rifted continental margin North Atlantic Igneous Province Ocean Bottom Seismometers Seismic tomography LARGE IGNEOUS PROVINCES OCEANIC CRUSTAL THICKNESS SPREAD SEISMIC PROFILES FAEROE-SHETLAND BASIN FAROE-ISLANDS BASALT FLOWS NE ATLANTIC FLOOD BASALTS ROCKS MANTLE Journal Article 2011 ftunivauckland https://doi.org/10.1016/j.tecto.2010.02.001 2013-12-07T09:10:16Z Imaging challenges caused by highly attenuative flood basalt sequences have resulted in the understanding of volcanic rifted continental margins lagging behind that of non-volcanic rifted and convergent margins. Massive volcanism occurred during break-up at 70% of the passive margins bordering the Atlantic Ocean, the causes and dynamics of which are still debated. This paper shows results from traveltime tomography of compressional and converted shear wave arrivals recorded on 170 four-component ocean bottom seismometers along two North Atlantic continental margin profiles. This traveltime tomography was performed using two different approaches. The first, a flexible layer-based parameterisation, enables the quality control of traveltime picks and investigation of the crustal structure. The second, with a regularised grid-based parameterisation, requires correction of converted shear wave traveltimes to effective symmetric raypaths and allows exploration of the model space via Monte Carlo analyses.The velocity models indicate high lower-crustal velocities and sharp transitions in both velocity and Vp/Vs ratios across the continent-ocean transition. The velocities are consistent with established mixing trends between felsic continental crust and high magnesium mafic rock on both margins. Interpretation of the high quality seismic reflection profile on the Faroes margin confirms that this mixing is through crustal intrusion. Converted shear wave data also provide constraints on the sub-basalt lithology on the Farces margin, which is interpreted as a pre-break-up Mesozoic to Paleocene sedimentary system intruded by sills. (C) 2010 Elsevier B.V. All rights reserved. Article in Journal/Newspaper Faroe Islands Faroes North Atlantic University of Auckland Research Repository - ResearchSpace Faroe Islands Tectonophysics 508 1-4 22 33 |
institution |
Open Polar |
collection |
University of Auckland Research Repository - ResearchSpace |
op_collection_id |
ftunivauckland |
language |
English |
topic |
Science & Technology Physical Sciences Geochemistry & Geophysics Volcanic rifted continental margin North Atlantic Igneous Province Ocean Bottom Seismometers Seismic tomography LARGE IGNEOUS PROVINCES OCEANIC CRUSTAL THICKNESS SPREAD SEISMIC PROFILES FAEROE-SHETLAND BASIN FAROE-ISLANDS BASALT FLOWS NE ATLANTIC FLOOD BASALTS ROCKS MANTLE |
spellingShingle |
Science & Technology Physical Sciences Geochemistry & Geophysics Volcanic rifted continental margin North Atlantic Igneous Province Ocean Bottom Seismometers Seismic tomography LARGE IGNEOUS PROVINCES OCEANIC CRUSTAL THICKNESS SPREAD SEISMIC PROFILES FAEROE-SHETLAND BASIN FAROE-ISLANDS BASALT FLOWS NE ATLANTIC FLOOD BASALTS ROCKS MANTLE Eccles, JD White, RS Christie, PAF The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
topic_facet |
Science & Technology Physical Sciences Geochemistry & Geophysics Volcanic rifted continental margin North Atlantic Igneous Province Ocean Bottom Seismometers Seismic tomography LARGE IGNEOUS PROVINCES OCEANIC CRUSTAL THICKNESS SPREAD SEISMIC PROFILES FAEROE-SHETLAND BASIN FAROE-ISLANDS BASALT FLOWS NE ATLANTIC FLOOD BASALTS ROCKS MANTLE |
description |
Imaging challenges caused by highly attenuative flood basalt sequences have resulted in the understanding of volcanic rifted continental margins lagging behind that of non-volcanic rifted and convergent margins. Massive volcanism occurred during break-up at 70% of the passive margins bordering the Atlantic Ocean, the causes and dynamics of which are still debated. This paper shows results from traveltime tomography of compressional and converted shear wave arrivals recorded on 170 four-component ocean bottom seismometers along two North Atlantic continental margin profiles. This traveltime tomography was performed using two different approaches. The first, a flexible layer-based parameterisation, enables the quality control of traveltime picks and investigation of the crustal structure. The second, with a regularised grid-based parameterisation, requires correction of converted shear wave traveltimes to effective symmetric raypaths and allows exploration of the model space via Monte Carlo analyses.The velocity models indicate high lower-crustal velocities and sharp transitions in both velocity and Vp/Vs ratios across the continent-ocean transition. The velocities are consistent with established mixing trends between felsic continental crust and high magnesium mafic rock on both margins. Interpretation of the high quality seismic reflection profile on the Faroes margin confirms that this mixing is through crustal intrusion. Converted shear wave data also provide constraints on the sub-basalt lithology on the Farces margin, which is interpreted as a pre-break-up Mesozoic to Paleocene sedimentary system intruded by sills. (C) 2010 Elsevier B.V. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Eccles, JD White, RS Christie, PAF |
author_facet |
Eccles, JD White, RS Christie, PAF |
author_sort |
Eccles, JD |
title |
The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
title_short |
The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
title_full |
The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
title_fullStr |
The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
title_full_unstemmed |
The composition and structure of volcanic rifted continental margins in the North Atlantic: Further insight from shear waves |
title_sort |
composition and structure of volcanic rifted continental margins in the north atlantic: further insight from shear waves |
publisher |
ELSEVIER SCIENCE BV |
publishDate |
2011 |
url |
http://hdl.handle.net/2292/19108 https://doi.org/10.1016/j.tecto.2010.02.001 |
geographic |
Faroe Islands |
geographic_facet |
Faroe Islands |
genre |
Faroe Islands Faroes North Atlantic |
genre_facet |
Faroe Islands Faroes North Atlantic |
op_source |
http://dx.doi.org/10.1016/j.tecto.2010.02.001 |
op_relation |
Tectonophysics |
op_rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. Details obtained from http://www.sherpa.ac.uk/romeo/issn/0040-1951/ https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm Copyright: ELSEVIER SCIENCE BV http://purl.org/eprint/accessRights/RestrictedAccess |
op_doi |
https://doi.org/10.1016/j.tecto.2010.02.001 |
container_title |
Tectonophysics |
container_volume |
508 |
container_issue |
1-4 |
container_start_page |
22 |
op_container_end_page |
33 |
_version_ |
1765996122748223488 |