The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover
The first U-Pb and Hf-Lu isotopic data of detrital zircons from Devonian strata of the Malvinas (Falkland) Islands allow re-evaluation of different hypotheses regarding their location before the breakup of Gondwana. Of the various published hypotheses there are only two that have gained support. Adi...
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2017
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_08959811_v76_n_p320_Ramos http://hdl.handle.net/20.500.12110/paper_08959811_v76_n_p320_Ramos |
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paper:paper_08959811_v76_n_p320_Ramos2023-06-08T15:48:58Z The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover Block rotation Detrital zircons Malvinas (Falkland) Plateau Paleogeography Patagonia U-Pb and Lu-Hf isotopes detrital deposit Gondwana hafnium isotopic analysis lutetium paleogeography Paleozoic tectonic evolution uranium-lead dating zircon Falkland Islands (Malvinas) Patagonia The first U-Pb and Hf-Lu isotopic data of detrital zircons from Devonian strata of the Malvinas (Falkland) Islands allow re-evaluation of different hypotheses regarding their location before the breakup of Gondwana. Of the various published hypotheses there are only two that have gained support. Adie's hypothesis involves a rotation of 180 degrees of the islands and a large displacement of Patagonia, independently of South America, whereas Borrello's hypothesis assumes a relative fixed position of the islands with respect to South America over time. The first hypothesis has traditionally been evaluated by highlighting the similarities of the geology of the Malvinas Islands with similar rocks cropping out in South Africa. In this paper we test those hypotheses that led to correlate the islands with the Cape System, based on geological, paleomagnetic and geochronological data. However, new isotopic data compared with contemporaneous Patagonian rocks, together with the present knowledge of offshore features of the Malvinas Plateau, suggest that its correlation with South Africa is not as compelling. Although there is no conclusive evidence, the simplest hypothesis based on the present available datasets, favors a closer relationship with Patagonia. No doubt that more research is needed in order to elucidate the paleogeography of the Malvinas Islands before the opening of the South Atlantic Ocean. © 2017 Elsevier Ltd 2017 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_08959811_v76_n_p320_Ramos http://hdl.handle.net/20.500.12110/paper_08959811_v76_n_p320_Ramos |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Block rotation Detrital zircons Malvinas (Falkland) Plateau Paleogeography Patagonia U-Pb and Lu-Hf isotopes detrital deposit Gondwana hafnium isotopic analysis lutetium paleogeography Paleozoic tectonic evolution uranium-lead dating zircon Falkland Islands (Malvinas) Patagonia |
| spellingShingle |
Block rotation Detrital zircons Malvinas (Falkland) Plateau Paleogeography Patagonia U-Pb and Lu-Hf isotopes detrital deposit Gondwana hafnium isotopic analysis lutetium paleogeography Paleozoic tectonic evolution uranium-lead dating zircon Falkland Islands (Malvinas) Patagonia The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| topic_facet |
Block rotation Detrital zircons Malvinas (Falkland) Plateau Paleogeography Patagonia U-Pb and Lu-Hf isotopes detrital deposit Gondwana hafnium isotopic analysis lutetium paleogeography Paleozoic tectonic evolution uranium-lead dating zircon Falkland Islands (Malvinas) Patagonia |
| description |
The first U-Pb and Hf-Lu isotopic data of detrital zircons from Devonian strata of the Malvinas (Falkland) Islands allow re-evaluation of different hypotheses regarding their location before the breakup of Gondwana. Of the various published hypotheses there are only two that have gained support. Adie's hypothesis involves a rotation of 180 degrees of the islands and a large displacement of Patagonia, independently of South America, whereas Borrello's hypothesis assumes a relative fixed position of the islands with respect to South America over time. The first hypothesis has traditionally been evaluated by highlighting the similarities of the geology of the Malvinas Islands with similar rocks cropping out in South Africa. In this paper we test those hypotheses that led to correlate the islands with the Cape System, based on geological, paleomagnetic and geochronological data. However, new isotopic data compared with contemporaneous Patagonian rocks, together with the present knowledge of offshore features of the Malvinas Plateau, suggest that its correlation with South Africa is not as compelling. Although there is no conclusive evidence, the simplest hypothesis based on the present available datasets, favors a closer relationship with Patagonia. No doubt that more research is needed in order to elucidate the paleogeography of the Malvinas Islands before the opening of the South Atlantic Ocean. © 2017 Elsevier Ltd |
| title |
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| title_short |
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| title_full |
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| title_fullStr |
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| title_full_unstemmed |
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover |
| title_sort |
malvinas (falkland) islands revisited: the tectonic evolution of southern gondwana based on u-pb and lu-hf detrital zircon isotopes in the paleozoic cover |
| publishDate |
2017 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_08959811_v76_n_p320_Ramos http://hdl.handle.net/20.500.12110/paper_08959811_v76_n_p320_Ramos |
| _version_ |
1768544964669603840 |