Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea
Eight hydrocarbon exploration wells in the southern Labrador Sea penetrated Precambrian basement rocks, adjacent to the course of a Lithoprobe marine seismic reflection survey. The rock types are mostly Early Proterozoic (1870–1800 Ma) calc-alkaline plutonic rocks or their metamorphic derivatives, b...
Published in: | Canadian Journal of Earth Sciences |
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1997
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Online Access: | http://dx.doi.org/10.1139/e17-017 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-017 |
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crcansciencepubl:10.1139/e17-017 2023-12-17T10:31:01+01:00 Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea Kerr, Andrew Wardle, Richard J. 1997 http://dx.doi.org/10.1139/e17-017 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-017 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 34, issue 2, page 209-214 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1997 crcansciencepubl https://doi.org/10.1139/e17-017 2023-11-19T13:38:28Z Eight hydrocarbon exploration wells in the southern Labrador Sea penetrated Precambrian basement rocks, adjacent to the course of a Lithoprobe marine seismic reflection survey. The rock types are mostly Early Proterozoic (1870–1800 Ma) calc-alkaline plutonic rocks or their metamorphic derivatives, but one example is a Middle Proterozoic (1270 Ma) anorogenic intrusion. These samples of buried basement document a transition from juvenile Proterozoic crust in the southeast (shown by ε Nd from +0.8 to +2.2) to ancient Archean crust in the northwest (shown by ε Nd from −2.7 to −7.0). However, initial Sr isotope ratios do not show such a clear pattern. The transition in ε Nd is similar to results of onland studies in Labrador and formerly adjacent south Greenland, and delimits the hidden edge of the North Atlantic Archean craton within the Early Proterozoic Makkovikian–Ketilidian Orogen. These results from close to the seismic profile confirm that regional reflectivity contrasts on either side of the isotopic boundary record fundamental differences between local Archean and Proterozoic crust. Southeast-dipping reflectors that broadly correspond with the boundary zone probably represent a collisional suture zone, along which juvenile terranes were probably placed structurally above the Archean craton. Article in Journal/Newspaper Greenland Labrador Sea North Atlantic Canadian Science Publishing (via Crossref) Greenland Canadian Journal of Earth Sciences 34 2 209 214 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Kerr, Andrew Wardle, Richard J. Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
topic_facet |
General Earth and Planetary Sciences |
description |
Eight hydrocarbon exploration wells in the southern Labrador Sea penetrated Precambrian basement rocks, adjacent to the course of a Lithoprobe marine seismic reflection survey. The rock types are mostly Early Proterozoic (1870–1800 Ma) calc-alkaline plutonic rocks or their metamorphic derivatives, but one example is a Middle Proterozoic (1270 Ma) anorogenic intrusion. These samples of buried basement document a transition from juvenile Proterozoic crust in the southeast (shown by ε Nd from +0.8 to +2.2) to ancient Archean crust in the northwest (shown by ε Nd from −2.7 to −7.0). However, initial Sr isotope ratios do not show such a clear pattern. The transition in ε Nd is similar to results of onland studies in Labrador and formerly adjacent south Greenland, and delimits the hidden edge of the North Atlantic Archean craton within the Early Proterozoic Makkovikian–Ketilidian Orogen. These results from close to the seismic profile confirm that regional reflectivity contrasts on either side of the isotopic boundary record fundamental differences between local Archean and Proterozoic crust. Southeast-dipping reflectors that broadly correspond with the boundary zone probably represent a collisional suture zone, along which juvenile terranes were probably placed structurally above the Archean craton. |
format |
Article in Journal/Newspaper |
author |
Kerr, Andrew Wardle, Richard J. |
author_facet |
Kerr, Andrew Wardle, Richard J. |
author_sort |
Kerr, Andrew |
title |
Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
title_short |
Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
title_full |
Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
title_fullStr |
Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
title_full_unstemmed |
Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea |
title_sort |
definition of an archean – proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern labrador sea |
publisher |
Canadian Science Publishing |
publishDate |
1997 |
url |
http://dx.doi.org/10.1139/e17-017 http://www.nrcresearchpress.com/doi/pdf/10.1139/e17-017 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Labrador Sea North Atlantic |
genre_facet |
Greenland Labrador Sea North Atlantic |
op_source |
Canadian Journal of Earth Sciences volume 34, issue 2, page 209-214 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e17-017 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
34 |
container_issue |
2 |
container_start_page |
209 |
op_container_end_page |
214 |
_version_ |
1785584169654419456 |