Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar?
The northern Madurai Block, southern India, lies directly south of, and partly deformed by, the Palghat–Cauvery Shear Zone System (PCSS) – a potential suture of the Neoproterozoic Mozambique Ocean. The Kadavur gabbro-anorthosite complex lies south of the PCSS, in the northern Madurai Block, and crys...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
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Pergamon-Elsevier Science Ltd
2011
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| Online Access: | http://hdl.handle.net/20.500.11937/29823 |
| _version_ | 1848752910202044416 |
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| author | Teale, W. Collins, A. Foden, J. Payne, J. Plavsa, Diana Chetty, T. Santosh, M. Fanning, M. |
| author_facet | Teale, W. Collins, A. Foden, J. Payne, J. Plavsa, Diana Chetty, T. Santosh, M. Fanning, M. |
| author_sort | Teale, W. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The northern Madurai Block, southern India, lies directly south of, and partly deformed by, the Palghat–Cauvery Shear Zone System (PCSS) – a potential suture of the Neoproterozoic Mozambique Ocean. The Kadavur gabbro-anorthosite complex lies south of the PCSS, in the northern Madurai Block, and crystallized at 829 ± 14 Ma (LA-ICPMS zircon data) in a supra-subduction zone setting. The complex contains zircon εHf(t) values of −12.5 to −8.6 that represent Palaeoproterozoic T(DM) model ages (2.3–2.5 Ga). These broadly agree with a whole rock neodymium T(DM) model age of 2287 Ma. Oxygen isotope δ18O ratios range from 5.82‰ and 6.74‰. The parental magma for the gabbro-anorthosites are interpreted to be derived from a juvenile Neoproterozoic mantle contaminated by Mesoarchaean igneous infra-crustal sources. The gabbro-anorthosites intrude quartzites with dominantly Palaeoproterozoic detrital zircons that contain Neoarchaean and Mesoarchaean hafnium model ages. These quartzite zircons contain metamorphic rims that yield an age of 843 ± 23 Ma demonstrating the autochthonous nature of the gabbro-anorthosite complex. Later felsic magmatism is recorded by the 766 ± 8 Ma crystallisation age of the protolith of a felsic gneiss. Cryogenian magmatism in the Madurai Block is interpreted to form part of an extensive arc magmatic province within the southern East African Orogen that can be traced from central Madagascar, through southern India to the Wanni Complex of Sri Lanka. This province is interpreted to have formed above a south/west dipping subduction system as the Mozambique Ocean was subducted under the Neoproterozoic continent Azania. |
| first_indexed | 2025-11-14T08:16:07Z |
| format | Journal Article |
| id | curtin-20.500.11937-29823 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:16:07Z |
| publishDate | 2011 |
| publisher | Pergamon-Elsevier Science Ltd |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-298232017-09-13T15:29:59Z Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? Teale, W. Collins, A. Foden, J. Payne, J. Plavsa, Diana Chetty, T. Santosh, M. Fanning, M. LA-ICPMS Zircon geochronology Madurai Block Azania Gondwana Mozambique Ocean Southern India Hf δ18O The northern Madurai Block, southern India, lies directly south of, and partly deformed by, the Palghat–Cauvery Shear Zone System (PCSS) – a potential suture of the Neoproterozoic Mozambique Ocean. The Kadavur gabbro-anorthosite complex lies south of the PCSS, in the northern Madurai Block, and crystallized at 829 ± 14 Ma (LA-ICPMS zircon data) in a supra-subduction zone setting. The complex contains zircon εHf(t) values of −12.5 to −8.6 that represent Palaeoproterozoic T(DM) model ages (2.3–2.5 Ga). These broadly agree with a whole rock neodymium T(DM) model age of 2287 Ma. Oxygen isotope δ18O ratios range from 5.82‰ and 6.74‰. The parental magma for the gabbro-anorthosites are interpreted to be derived from a juvenile Neoproterozoic mantle contaminated by Mesoarchaean igneous infra-crustal sources. The gabbro-anorthosites intrude quartzites with dominantly Palaeoproterozoic detrital zircons that contain Neoarchaean and Mesoarchaean hafnium model ages. These quartzite zircons contain metamorphic rims that yield an age of 843 ± 23 Ma demonstrating the autochthonous nature of the gabbro-anorthosite complex. Later felsic magmatism is recorded by the 766 ± 8 Ma crystallisation age of the protolith of a felsic gneiss. Cryogenian magmatism in the Madurai Block is interpreted to form part of an extensive arc magmatic province within the southern East African Orogen that can be traced from central Madagascar, through southern India to the Wanni Complex of Sri Lanka. This province is interpreted to have formed above a south/west dipping subduction system as the Mozambique Ocean was subducted under the Neoproterozoic continent Azania. 2011 Journal Article http://hdl.handle.net/20.500.11937/29823 10.1016/j.jseaes.2011.04.006 Pergamon-Elsevier Science Ltd restricted |
| spellingShingle | LA-ICPMS Zircon geochronology Madurai Block Azania Gondwana Mozambique Ocean Southern India Hf δ18O Teale, W. Collins, A. Foden, J. Payne, J. Plavsa, Diana Chetty, T. Santosh, M. Fanning, M. Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title | Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title_full | Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title_fullStr | Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title_full_unstemmed | Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title_short | Cryogenian (~830 Ma) mafic magmatism and metamorphism in the northern Madurai Block, southern India: A magmatic link between Sri Lanka and Madagascar? |
| title_sort | cryogenian (~830 ma) mafic magmatism and metamorphism in the northern madurai block, southern india: a magmatic link between sri lanka and madagascar? |
| topic | LA-ICPMS Zircon geochronology Madurai Block Azania Gondwana Mozambique Ocean Southern India Hf δ18O |
| url | http://hdl.handle.net/20.500.11937/29823 |