Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations
The evolution of the passive margin off the coast of Eastern Canada has been characterized by a series of rifting episodes which caused widespread extension of the lithosphere and associated structural anomalies, some with the potential to be classified as a result of lithospheric boudinage. Crustal...
Published in: | Geosciences |
---|---|
Main Authors: | , , |
Format: | Text |
Language: | English |
Published: |
Multidisciplinary Digital Publishing Institute
2021
|
Subjects: | |
Online Access: | https://doi.org/10.3390/geosciences11020055 |
id |
ftmdpi:oai:mdpi.com:/2076-3263/11/2/55/ |
---|---|
record_format |
openpolar |
spelling |
ftmdpi:oai:mdpi.com:/2076-3263/11/2/55/ 2023-08-20T04:07:53+02:00 Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations Malcolm D. J. MacDougall Alexander Braun Georgia Fotopoulos agris 2021-01-28 application/pdf https://doi.org/10.3390/geosciences11020055 EN eng Multidisciplinary Digital Publishing Institute Structural Geology and Tectonics https://dx.doi.org/10.3390/geosciences11020055 https://creativecommons.org/licenses/by/4.0/ Geosciences; Volume 11; Issue 2; Pages: 55 geophysical interpretation passive margin evolution seismic interpretation boudinage grand banks extensional tectonics Text 2021 ftmdpi https://doi.org/10.3390/geosciences11020055 2023-08-01T00:57:35Z The evolution of the passive margin off the coast of Eastern Canada has been characterized by a series of rifting episodes which caused widespread extension of the lithosphere and associated structural anomalies, some with the potential to be classified as a result of lithospheric boudinage. Crustal thinning of competent layers is often apparent in seismic sections, and deeper Moho undulations may appear as repeating elongated anomalies in gravity and magnetic surveys. By comparing the similar evolutions of the Grand Banks and the Norwegian Lofoten-Vesterålen passive margins, it is reasonable to explore the potential of the same structures being present. This investigation supplements our knowledge of analogous examples in the Norwegian Margin and the South China Sea with a thorough investigation of seismic, gravity and magnetic signatures, to determine that boudinage structures are evident in the context of the Grand Banks. Through analysis of geophysical data (including seismic, gravity and magnetic observations), a multi-stage boudinage mechanism is proposed, which is characterized by an upper crust short-wavelength deformation ranging from approximately 20–80 km and a lower crust long-wavelength deformation exceeding 200 km in length. In addition, the boudinage mechanism caused slightly different structures which are apparent in the block geometry and layeredness. Based on these results, there are indications that boudinage wavelength increases with each successive rifting phase, with geometry changing from domino style to a more shearband/symmetrical style as the scale of deformation is increased to include the entire lithosphere. Text Lofoten Newfoundland Vesterålen MDPI Open Access Publishing Canada Lofoten Vesterålen ENVELOPE(14.939,14.939,68.754,68.754) Geosciences 11 2 55 |
institution |
Open Polar |
collection |
MDPI Open Access Publishing |
op_collection_id |
ftmdpi |
language |
English |
topic |
geophysical interpretation passive margin evolution seismic interpretation boudinage grand banks extensional tectonics |
spellingShingle |
geophysical interpretation passive margin evolution seismic interpretation boudinage grand banks extensional tectonics Malcolm D. J. MacDougall Alexander Braun Georgia Fotopoulos Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
topic_facet |
geophysical interpretation passive margin evolution seismic interpretation boudinage grand banks extensional tectonics |
description |
The evolution of the passive margin off the coast of Eastern Canada has been characterized by a series of rifting episodes which caused widespread extension of the lithosphere and associated structural anomalies, some with the potential to be classified as a result of lithospheric boudinage. Crustal thinning of competent layers is often apparent in seismic sections, and deeper Moho undulations may appear as repeating elongated anomalies in gravity and magnetic surveys. By comparing the similar evolutions of the Grand Banks and the Norwegian Lofoten-Vesterålen passive margins, it is reasonable to explore the potential of the same structures being present. This investigation supplements our knowledge of analogous examples in the Norwegian Margin and the South China Sea with a thorough investigation of seismic, gravity and magnetic signatures, to determine that boudinage structures are evident in the context of the Grand Banks. Through analysis of geophysical data (including seismic, gravity and magnetic observations), a multi-stage boudinage mechanism is proposed, which is characterized by an upper crust short-wavelength deformation ranging from approximately 20–80 km and a lower crust long-wavelength deformation exceeding 200 km in length. In addition, the boudinage mechanism caused slightly different structures which are apparent in the block geometry and layeredness. Based on these results, there are indications that boudinage wavelength increases with each successive rifting phase, with geometry changing from domino style to a more shearband/symmetrical style as the scale of deformation is increased to include the entire lithosphere. |
format |
Text |
author |
Malcolm D. J. MacDougall Alexander Braun Georgia Fotopoulos |
author_facet |
Malcolm D. J. MacDougall Alexander Braun Georgia Fotopoulos |
author_sort |
Malcolm D. J. MacDougall |
title |
Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
title_short |
Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
title_full |
Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
title_fullStr |
Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
title_full_unstemmed |
Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations |
title_sort |
evidence of lithospheric boudinage in the grand banks of newfoundland from geophysical observations |
publisher |
Multidisciplinary Digital Publishing Institute |
publishDate |
2021 |
url |
https://doi.org/10.3390/geosciences11020055 |
op_coverage |
agris |
long_lat |
ENVELOPE(14.939,14.939,68.754,68.754) |
geographic |
Canada Lofoten Vesterålen |
geographic_facet |
Canada Lofoten Vesterålen |
genre |
Lofoten Newfoundland Vesterålen |
genre_facet |
Lofoten Newfoundland Vesterålen |
op_source |
Geosciences; Volume 11; Issue 2; Pages: 55 |
op_relation |
Structural Geology and Tectonics https://dx.doi.org/10.3390/geosciences11020055 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/geosciences11020055 |
container_title |
Geosciences |
container_volume |
11 |
container_issue |
2 |
container_start_page |
55 |
_version_ |
1774719806851776512 |