Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique
Lithospheric thickening during protracted Ediacaran supercontinent assembly was dissipated in various ways along the “Pan-African” East African–Antarctic Orogen. In NE Mozambique, late-tectonic extension and plutonism south of the Lúrio Belt has been modelled in terms of lithosphere delamination, al...
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ftcurtin:oai:espace.curtin.edu.au:20.500.11937/14680 2023-06-11T04:05:30+02:00 Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique Ueda, K. Jacobs, J. Thomas, R. Kosler, Jan. Jourdan, Fred Matola, R. 2012 restricted https://hdl.handle.net/20.500.11937/14680 https://doi.org/10.1016/j.precamres.2011.05.012 unknown Elsevier BV http://hdl.handle.net/20.500.11937/14680 doi:10.1016/j.precamres.2011.05.012 Mecubúri Lurio Belt Mozambique Extensional folding Delamination Journal Article 2012 ftcurtin https://doi.org/20.500.11937/1468010.1016/j.precamres.2011.05.012 2023-05-30T19:27:34Z Lithospheric thickening during protracted Ediacaran supercontinent assembly was dissipated in various ways along the “Pan-African” East African–Antarctic Orogen. In NE Mozambique, late-tectonic extension and plutonism south of the Lúrio Belt has been modelled in terms of lithosphere delamination, although rigorous testing of the hypothesis by structural analysis has not yet been undertaken. This study presents the first analyses of late-tectonic structures in both the Mesoproterozoic basement and the Cambrian cover sequences in the Nampula Complex, NE Mozambique, supported by, and integrated with, new geochronological data. Both late compressional and extensional fabrics overprint the main Pan-African collisional structures to a variable degree in identified structural domains. The long-lived northern boundary of the Nampula Complex, the Lúrio Belt high-strain zone, initiated in the Ediacaran, was reactivated and segmented during these later phases, with boundary-parallel shortening. U–Pb SIMS ages from selected latest-tectonic units in the Nampula Complex and the Lúrio Belt give consistent ages between 518 ± 2 and 514 ± 5 Ma. They are coeval with migmatisation and granitoid plutonism in the Nampula Complex. U–Pb titanite (471 ± 9 Ma) and 40Ar/39Ar biotite (431 ± 3 Ma) data suggest subsequent slow cooling rates in the Nampula Complex, consistent with basal heating by asthenosphere uprise following lithosphere delamination. Consequently, we believe the new data suggest that the observed intense late polyphase deformation has preferentially occurred where the delaminated lithosphere was doubly weakened by loss of the mantle root and the resulting long-lived elevated temperature regime. Article in Journal/Newspaper Antarc* Antarctic Curtin University: espace Antarctic Precambrian Research 196-197 275 294 |
institution |
Open Polar |
collection |
Curtin University: espace |
op_collection_id |
ftcurtin |
language |
unknown |
topic |
Mecubúri Lurio Belt Mozambique Extensional folding Delamination |
spellingShingle |
Mecubúri Lurio Belt Mozambique Extensional folding Delamination Ueda, K. Jacobs, J. Thomas, R. Kosler, Jan. Jourdan, Fred Matola, R. Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
topic_facet |
Mecubúri Lurio Belt Mozambique Extensional folding Delamination |
description |
Lithospheric thickening during protracted Ediacaran supercontinent assembly was dissipated in various ways along the “Pan-African” East African–Antarctic Orogen. In NE Mozambique, late-tectonic extension and plutonism south of the Lúrio Belt has been modelled in terms of lithosphere delamination, although rigorous testing of the hypothesis by structural analysis has not yet been undertaken. This study presents the first analyses of late-tectonic structures in both the Mesoproterozoic basement and the Cambrian cover sequences in the Nampula Complex, NE Mozambique, supported by, and integrated with, new geochronological data. Both late compressional and extensional fabrics overprint the main Pan-African collisional structures to a variable degree in identified structural domains. The long-lived northern boundary of the Nampula Complex, the Lúrio Belt high-strain zone, initiated in the Ediacaran, was reactivated and segmented during these later phases, with boundary-parallel shortening. U–Pb SIMS ages from selected latest-tectonic units in the Nampula Complex and the Lúrio Belt give consistent ages between 518 ± 2 and 514 ± 5 Ma. They are coeval with migmatisation and granitoid plutonism in the Nampula Complex. U–Pb titanite (471 ± 9 Ma) and 40Ar/39Ar biotite (431 ± 3 Ma) data suggest subsequent slow cooling rates in the Nampula Complex, consistent with basal heating by asthenosphere uprise following lithosphere delamination. Consequently, we believe the new data suggest that the observed intense late polyphase deformation has preferentially occurred where the delaminated lithosphere was doubly weakened by loss of the mantle root and the resulting long-lived elevated temperature regime. |
format |
Article in Journal/Newspaper |
author |
Ueda, K. Jacobs, J. Thomas, R. Kosler, Jan. Jourdan, Fred Matola, R. |
author_facet |
Ueda, K. Jacobs, J. Thomas, R. Kosler, Jan. Jourdan, Fred Matola, R. |
author_sort |
Ueda, K. |
title |
Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
title_short |
Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
title_full |
Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
title_fullStr |
Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
title_full_unstemmed |
Delamination-induced late-tectonic deformation and high-grade metamorphism of the Proterozoic Nampula Complex, northern Mozambique |
title_sort |
delamination-induced late-tectonic deformation and high-grade metamorphism of the proterozoic nampula complex, northern mozambique |
publisher |
Elsevier BV |
publishDate |
2012 |
url |
https://hdl.handle.net/20.500.11937/14680 https://doi.org/10.1016/j.precamres.2011.05.012 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://hdl.handle.net/20.500.11937/14680 doi:10.1016/j.precamres.2011.05.012 |
op_doi |
https://doi.org/20.500.11937/1468010.1016/j.precamres.2011.05.012 |
container_title |
Precambrian Research |
container_volume |
196-197 |
container_start_page |
275 |
op_container_end_page |
294 |
_version_ |
1768376440332484608 |