Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening
Seismic reflection and refraction data from the SE Greenland margin provide a detailed view of a volcanic rifted margin from Archean continental crust to near-to-average oceanic crust over a spatial scale of 400 km. The SIGMA III transect, located ∼600 km south of the Greenland-Iceland Ridge and the...
Published in: | Journal of Geophysical Research: Solid Earth |
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Language: | English |
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Online Access: | https://oceanrep.geomar.de/id/eprint/2588/ https://oceanrep.geomar.de/id/eprint/2588/1/Hopper.pdf http://www.agu.org/pubs/crossref/2003/2002JB001996.shtml https://doi.org/10.1029/2002JB001996 |
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ftoceanrep:oai:oceanrep.geomar.de:2588 2023-05-15T16:27:04+02:00 Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening Hopper, J. R. Dahl-Jensen, T. Holbrook, W. S. Larsen, H. C. Lizarralde, D. Korenaga, J. Kent, G. M. Kelemen, P. B. 2003 text https://oceanrep.geomar.de/id/eprint/2588/ https://oceanrep.geomar.de/id/eprint/2588/1/Hopper.pdf http://www.agu.org/pubs/crossref/2003/2002JB001996.shtml https://doi.org/10.1029/2002JB001996 en eng AGU https://oceanrep.geomar.de/id/eprint/2588/1/Hopper.pdf Hopper, J. R., Dahl-Jensen, T., Holbrook, W. S., Larsen, H. C., Lizarralde, D., Korenaga, J., Kent, G. M. and Kelemen, P. B. (2003) Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening. Journal of Geophysical Research: Solid Earth, 108 (B5). p. 2269. DOI 10.1029/2002JB001996 <https://doi.org/10.1029/2002JB001996>. doi:10.1029/2002JB001996 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2003 ftoceanrep https://doi.org/10.1029/2002JB001996 2023-04-07T14:46:12Z Seismic reflection and refraction data from the SE Greenland margin provide a detailed view of a volcanic rifted margin from Archean continental crust to near-to-average oceanic crust over a spatial scale of 400 km. The SIGMA III transect, located ∼600 km south of the Greenland-Iceland Ridge and the presumed track of the Iceland hot spot, shows that the continent-ocean transition is abrupt and only a small amount of crustal thinning occurred prior to final breakup. Initially, 18.3 km thick crust accreted to the margin and the productivity decreased through time until a steady state ridge system was established that produced 8–10 km thick crust. Changes in the morphology of the basaltic extrusives provide evidence for vertical motions of the ridge system, which was close to sea level for at least 1 m.y. of subaerial spreading despite a reduction in productivity from 17 to 13.5 km thick crust over this time interval. This could be explained if a small component of active upwelling associated with thermal buoyancy from a modest thermal anomaly provided dynamic support to the rift system. The thermal anomaly must be exhaustible, consistent with recent suggestions that plume material was emplaced into a preexisting lithospheric thin spot as a thin sheet. Exhaustion of the thin sheet led to rapid subsidence of the spreading system and a change from subaerial, to shallow marine, and finally to deep marine extrusion in ∼2 m.y. is shown by the morphological changes. In addition, comparison to the conjugate Hatton Bank shows a clear asymmetry in the early accretion history of North Atlantic oceanic crust. Nearly double the volume of material was emplaced on the Greenland margin compared to Hatton Bank and may indicate east directed ridge migration during initial opening. Article in Journal/Newspaper Greenland Iceland North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Greenland Hatton Bank ENVELOPE(-18.000,-18.000,58.583,58.583) Journal of Geophysical Research: Solid Earth 108 B5 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Seismic reflection and refraction data from the SE Greenland margin provide a detailed view of a volcanic rifted margin from Archean continental crust to near-to-average oceanic crust over a spatial scale of 400 km. The SIGMA III transect, located ∼600 km south of the Greenland-Iceland Ridge and the presumed track of the Iceland hot spot, shows that the continent-ocean transition is abrupt and only a small amount of crustal thinning occurred prior to final breakup. Initially, 18.3 km thick crust accreted to the margin and the productivity decreased through time until a steady state ridge system was established that produced 8–10 km thick crust. Changes in the morphology of the basaltic extrusives provide evidence for vertical motions of the ridge system, which was close to sea level for at least 1 m.y. of subaerial spreading despite a reduction in productivity from 17 to 13.5 km thick crust over this time interval. This could be explained if a small component of active upwelling associated with thermal buoyancy from a modest thermal anomaly provided dynamic support to the rift system. The thermal anomaly must be exhaustible, consistent with recent suggestions that plume material was emplaced into a preexisting lithospheric thin spot as a thin sheet. Exhaustion of the thin sheet led to rapid subsidence of the spreading system and a change from subaerial, to shallow marine, and finally to deep marine extrusion in ∼2 m.y. is shown by the morphological changes. In addition, comparison to the conjugate Hatton Bank shows a clear asymmetry in the early accretion history of North Atlantic oceanic crust. Nearly double the volume of material was emplaced on the Greenland margin compared to Hatton Bank and may indicate east directed ridge migration during initial opening. |
format |
Article in Journal/Newspaper |
author |
Hopper, J. R. Dahl-Jensen, T. Holbrook, W. S. Larsen, H. C. Lizarralde, D. Korenaga, J. Kent, G. M. Kelemen, P. B. |
spellingShingle |
Hopper, J. R. Dahl-Jensen, T. Holbrook, W. S. Larsen, H. C. Lizarralde, D. Korenaga, J. Kent, G. M. Kelemen, P. B. Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
author_facet |
Hopper, J. R. Dahl-Jensen, T. Holbrook, W. S. Larsen, H. C. Lizarralde, D. Korenaga, J. Kent, G. M. Kelemen, P. B. |
author_sort |
Hopper, J. R. |
title |
Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
title_short |
Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
title_full |
Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
title_fullStr |
Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
title_full_unstemmed |
Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening |
title_sort |
structure of the se greenland margin from seismic reflection and refraction data: implications for nascent spreading center subsidence and asymmetric crustal accretion during n atlantic opening |
publisher |
AGU |
publishDate |
2003 |
url |
https://oceanrep.geomar.de/id/eprint/2588/ https://oceanrep.geomar.de/id/eprint/2588/1/Hopper.pdf http://www.agu.org/pubs/crossref/2003/2002JB001996.shtml https://doi.org/10.1029/2002JB001996 |
long_lat |
ENVELOPE(-18.000,-18.000,58.583,58.583) |
geographic |
Greenland Hatton Bank |
geographic_facet |
Greenland Hatton Bank |
genre |
Greenland Iceland North Atlantic |
genre_facet |
Greenland Iceland North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/2588/1/Hopper.pdf Hopper, J. R., Dahl-Jensen, T., Holbrook, W. S., Larsen, H. C., Lizarralde, D., Korenaga, J., Kent, G. M. and Kelemen, P. B. (2003) Structure of the SE Greenland margin from seismic reflection and refraction data: Implications for nascent spreading center subsidence and asymmetric crustal accretion during N Atlantic opening. Journal of Geophysical Research: Solid Earth, 108 (B5). p. 2269. DOI 10.1029/2002JB001996 <https://doi.org/10.1029/2002JB001996>. doi:10.1029/2002JB001996 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1029/2002JB001996 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
108 |
container_issue |
B5 |
_version_ |
1766016126529044480 |