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The Western Sierras Pampeanas (WSP) of Argentina record a protracted geological history from the Mesoproterozoic assembly of the Rodinia supercontinent to the early Paleozoic tectonic evolution of SW Gondwana. Two well-known orogenies took place at the proto-Andean margin of Gondwana in the Cambrian and the Ordovician, i.e., the Pampean (545–520 Ma) and Famatinian (490–440 Ma) orogenies, respectively. Between them, an extensive continental platform was developed, where mixed carbonate–siliciclastic sedimentation occurred. This platform was later involved in the Famatinian orogeny when it underwent penetrative deformation and metamorphism. The platform apparently extended from Patagonia to northwestern Argentina and the Eastern Sierras Pampeanas, and has probable equivalents in SW Africa, Peru, and Bolivia. The WSP record the outer (deepest) part of the platform, where carbonates were deposited in addition to siliciclastic sediments. Detrital zircon U–Pb SHRIMP ages from clastic metasedimentary successions and Sr-isotope compositions of marbles from the WSP suggest depositional ages between ca. 525 and 490 Ma. The detrital zircon age patterns further suggest that clastic sedimentation took place in two stages. The first was sourced mainly from re-working of the underlying Neoproterozoic metasedimentary rocks and the uplifted core of the early Cambrian Pampean orogen, without input from the Paleoproterozoic Río de la Plata craton. Sediments of the second stage resulted from the erosion of the still emerged Pampean belt and the Neoproterozoic Brasiliano orogen in the NE with some contribution from the Río de la Plata craton. An important conclusion is that the WSP basement was already part of SW Gondwana in the early Cambrian, and not part of the exotic Precordillera/Cuyania terrane, as was previously thought., Funding was through Argentine public Grants PUE 2016 CONICET-CICTERRA, CONICET PIP 2015–2018 11220150100901CO, FONCYT PICT 0472, SECyT 2016–2017 Tipo A No. 30720150100517CB, and Spanish grants (CGL2009-07984), GR58/08 UCM-Santander and CGL2016-76439-P of MINECO.

Made available in DSpace on 2018-11-26T17:34:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-07-01 The publication of the comments by Vesely & Schemiko (Comment on From source-to-sink: The Late Permian SW Gondwana paleogeography and sedimentary dispersion unraveled by a multi-proxy analysis by L. Alessandretti, R. Machado, L.V. Warren, M.L. Assine and C. Lana [Journal of South American Earth Sciences 70 (2016) 368-382], Journal of South American Earth Sciences, this issue) on our paper entitled From source-to-sink: The Late Permian SW Gondwana paleogeography and sedimentary dispersion unraveled by a multi -proxy analysis (L. Alessandretti, R. Machado, L.V. Warren, M.L. Assine and C. Lana (Journal of South American Earth Sciences 70 (2016) 368-382) provides a worthy opportunity to further clarify our observations and interpretations regarding the provenance of the Late Permian Rio do Rasto Formation and its implications on SW Gondwana paleogeography and sedimentary dispersion. (C) 2017 Elsevier Ltd. All rights reserved. Univ Sao Paulo, Inst Geociencias, Rua Lago,562 Cidade Univ, BR-05508080 Sao Paulo, SP, Brazil Univ Estadual Paulista, Dept Geol Aplicada, Inst Geociencias & Ciencias Exatas, Ave 24-A, BR-13506900 Rio Claro, SP, Brazil Conselho Nacl Desenvolvimento Cientif & Tecnol, Brasilia, DF, Brazil Univ Fed Ouro Preto, Escola Minas, Dept Geol, BR-35400000 Ouro Preto, MG, Brazil Univ Estadual Paulista, Dept Geol Aplicada, Inst Geociencias & Ciencias Exatas, Ave 24-A, BR-13506900 Rio Claro, SP, Brazil