Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence
A paleomagnetic study of Eocene volcanic rocks in Patagonia yields high unblocking temperature and high-coercivity magnetizations. Combining these results with those of a previous study on Patagonian Eocene basalts yields a high-precision, high-quality pole located at latitude 81°S, longitude 337.4°...
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ftconicet:oai:ri.conicet.gov.ar:11336/76832 2023-10-09T21:51:04+02:00 Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence Somoza, Ruben application/pdf http://hdl.handle.net/11336/76832 eng eng American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2006JB004610 info:eu-repo/semantics/altIdentifier/url/https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006JB004610 http://hdl.handle.net/11336/76832 Somoza, Ruben; Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence; American Geophysical Union; Journal of Geophysical Research: Solid Earth; 112; 3; 3-2007; 1-11 0148-0227 CONICET Digital CONICET info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ South America paleomagnetic Eocene volcanic rocks Patagonia https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion ftconicet https://doi.org/10.1029/2006JB004610 2023-09-24T20:30:04Z A paleomagnetic study of Eocene volcanic rocks in Patagonia yields high unblocking temperature and high-coercivity magnetizations. Combining these results with those of a previous study on Patagonian Eocene basalts yields a high-precision, high-quality pole located at latitude 81°S, longitude 337.4°E, A95 = 5.7°. Critically, this paleopole is indistinguishable from that of the Late Cretaceous (circa 85-65 Ma) pole position of South America, indicating that the plate was essentially motionless with respect to the spin axis for a period of ∼45 m.y. The pole position places South America at higher (∼5°) than present-day latitudes during the Eocene, indicating that northward continental motion toward present-day latitudes must have been accomplished sometime since the late Eocene. Paleomagnetic and tectonic correlation admits the hypothesis that Cenozoic northward drift was associated with Oligocene-Miocene extension in the southern continental edge, leading to the opening of the Drake Passage, and it agrees with the timing of foredeep formation and development of fold-thrust belts in the northern continental edge. This positive correlation between the paleomagnetically predicted drift of a major continent with extension at its trailing edge and convergence at its leading edge during times for which seafloor tectonic fabric and the geological record are particularly well preserved illustrates the utility of paleomagnetism in constraining paleogeographic and tectonic reconstructions for pre-Cretaceous times. Fil: Somoza, Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina Article in Journal/Newspaper Drake Passage CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) Patagonia Drake Passage Argentina Journal of Geophysical Research 112 B3 |
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Open Polar |
collection |
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) |
op_collection_id |
ftconicet |
language |
English |
topic |
South America paleomagnetic Eocene volcanic rocks Patagonia https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
spellingShingle |
South America paleomagnetic Eocene volcanic rocks Patagonia https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 Somoza, Ruben Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
topic_facet |
South America paleomagnetic Eocene volcanic rocks Patagonia https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
description |
A paleomagnetic study of Eocene volcanic rocks in Patagonia yields high unblocking temperature and high-coercivity magnetizations. Combining these results with those of a previous study on Patagonian Eocene basalts yields a high-precision, high-quality pole located at latitude 81°S, longitude 337.4°E, A95 = 5.7°. Critically, this paleopole is indistinguishable from that of the Late Cretaceous (circa 85-65 Ma) pole position of South America, indicating that the plate was essentially motionless with respect to the spin axis for a period of ∼45 m.y. The pole position places South America at higher (∼5°) than present-day latitudes during the Eocene, indicating that northward continental motion toward present-day latitudes must have been accomplished sometime since the late Eocene. Paleomagnetic and tectonic correlation admits the hypothesis that Cenozoic northward drift was associated with Oligocene-Miocene extension in the southern continental edge, leading to the opening of the Drake Passage, and it agrees with the timing of foredeep formation and development of fold-thrust belts in the northern continental edge. This positive correlation between the paleomagnetically predicted drift of a major continent with extension at its trailing edge and convergence at its leading edge during times for which seafloor tectonic fabric and the geological record are particularly well preserved illustrates the utility of paleomagnetism in constraining paleogeographic and tectonic reconstructions for pre-Cretaceous times. Fil: Somoza, Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina |
format |
Article in Journal/Newspaper |
author |
Somoza, Ruben |
author_facet |
Somoza, Ruben |
author_sort |
Somoza, Ruben |
title |
Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
title_short |
Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
title_full |
Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
title_fullStr |
Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
title_full_unstemmed |
Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence |
title_sort |
eocene paleomagnetic pole for south america: northward continental motion in the cenozoic, opening of drake passage and caribbean convergence |
publisher |
American Geophysical Union |
url |
http://hdl.handle.net/11336/76832 |
geographic |
Patagonia Drake Passage Argentina |
geographic_facet |
Patagonia Drake Passage Argentina |
genre |
Drake Passage |
genre_facet |
Drake Passage |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2006JB004610 info:eu-repo/semantics/altIdentifier/url/https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006JB004610 http://hdl.handle.net/11336/76832 Somoza, Ruben; Eocene paleomagnetic pole for South America: Northward continental motion in the Cenozoic, opening of Drake Passage and Caribbean convergence; American Geophysical Union; Journal of Geophysical Research: Solid Earth; 112; 3; 3-2007; 1-11 0148-0227 CONICET Digital CONICET |
op_rights |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
op_doi |
https://doi.org/10.1029/2006JB004610 |
container_title |
Journal of Geophysical Research |
container_volume |
112 |
container_issue |
B3 |
_version_ |
1779314167700783104 |