| Full text | |
| Author(s): |
Total Authors: 3
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| Affiliation: | [1] Univ Estadual Campinas, UNICAMP, Dept Geol & Nat Resources, POB 6152, BR-13083970 Campinas, SP - Brazil
[2] Univ Estado Rio De Janeiro, Dept Geol, Rua Sao Francisco Xavier, 524 Room 4006A, BR-20559900 Rio De Janeiro - Brazil
Total Affiliations: 2
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| Document type: | Journal article |
| Source: | Journal of South American Earth Sciences; v. 79, p. 326-341, NOV 2017. |
| Web of Science Citations: | 3 |
| Abstract | |
Mafic-ultramafic complexes are common in ancient orogenic belts and can represent arc roots, obducted ophiolite remnants, continental intrusions, subducted oceanic plateaux or lithospheric mantle fragments. The Archaean-Palaeoproterozoic Itabuna-Salvador-Curaca Orogen hosts several mafic-ultramafic complexes, whose petrogenetic understanding is difficult owing to the high-grade metamorphism and deformation. One of these complexes is the 2583.7 +/- 7.7 Ma Sao Jose do Jacuipe Gabbro-Anorthosite Complex, composed of massive to stratiform, deformed and metamorphosed anorthosites, leucogabbros, and gabbros with minor pyroxenites. Field relationships of the mafic-ultramafic rocks combined with calcic-pyroxene chemistry, negative Nb anomalies in mantle-normalised diagrams, and dominantly positive epsilon(Nd(t)) values suggest similarities with arc mafic magmatism. The gabbro-anorthosite complex matches the ages of arc orthogneisses (2574 +/- 6 Ma) and norite-hypersthenite complex (2580 +/- 10 Ma) of the Caraiba Complex and is thus interpreted as a fragment of the root of the Neoarchaean Caraiba magmatic arc within the Itabuna-Salvador-Curaca Orogen. (C) 2017 Elsevier Ltd. All rights reserved. (AU) | |
| FAPESP's process: | 12/15824-6 - Evolution of archaean terranes of the São Francisco Craton and the Borborema Province, Brazil: global environmental and geodynamic implications |
| Grantee: | Elson Paiva de Oliveira |
| Support Opportunities: | Research Projects - Thematic Grants |