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Correlations of Some Neoproterozoic Carbonate-Dominated Successions

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Correlations of Some Neoproterozoic Carbonate-Dominated Successions DOI: 10.1590/2317-4889201620160079 INVITED REVIEW Correlations of some Neoproterozoic carbonate-dominated successions in South America based on high-resolution chemostratigraphy Correlações de algumas sucessões carbonáticas na América do Sul baseado em quimioestratigrafia de alta resolução Alcides Nobrega Sial1*, Claudio Gaucher2, Aroldo Misi3, Paulo Cesar Boggiani4, Carlos José Souza de Alvarenga5, Valderez Pinto Ferreira1, Marcio Martins Pimentel5, José Augusto Pedreira6, Lucas Verissimo Warren7, Rodrigo Fernández-Ramírez8, Mauro Geraldes9, Natan Silva Pereira1, Leticia Chiglino10, Wilker dos Santos Cezario1 ABSTRACT: This report reviews and incorporates new elemental and RESUMO: Esta revisão incorpora novos dados isotópicos e quími- isotope chemostratigraphic data for correlation of Neoproterozoic carbo- cos para correlação quimioestratigráfica de sucessões, predominante- nate-dominated successions in South America (Argentina, Bolivia, Brazil, mente carbonáticas, na América do Sul (Argentina, Bolívia, Brasil, Paraguay and Uruguay). These thick mixed carbonate/siliciclastic succes- Paraguai e Uruguai). Estas sucessões, depositadas durante eventos sions were largely deposited in epicontinental basins or accumulated on de extensão, aparecem como espessos estratos carbonáticos/siliciclásti- passive margins on the edges of cratons (e.g. São Francisco, Amazonia, cos em bacias epicontinentais ou foram acumulados sobre margens Rio Apa Block, Pampia and Río de la Plata paleocontinents) during ex- passivas em bordos de cratons (ex.: São Francisco, Amazonas, Blo- tensional events related to the rifting of the Rodinia Supercontinent. From co Rio Apa, Pampia e Río de La Plata) como três megasequências: the stratigraphic point of view, these successions occur as three mega-se- glaciogênica, plataforma marinha carbonática (sobre diamictitos quences: glaciogenic, marine carbonate platform (above glaciomarine dia- glacio-marinhos) e predominantemente continental siliciclástica. mictites or rift successions), and dominantly continental to transitional Em cinturões circunjacentes a cratons, sucessões carbonáticas con- siliciclastics. In the orogenic belts surrounding cratons, carbonate-domi- tendo material vulcanoclástico/siliciclástico foram, na maioria dos nated successions with important volcanoclastic/siliciclastic contribution casos, fortemente deformados. A idade precisa de sedimentação destas have been, in most cases, strongly deformed. The precise ages of these sucessões permanece em debate, mas recentes dados paleontológicos successions remain a matter of debate, but recently new paleontological e geocronológicos têm consideravelmente restringidos os intervalos and geochronological data have considerably constrained depositional de deposição. Neste trabalho, reportamos trends isotópicos de alta intervals. Here, we report high-resolution C, O, Sr, and S isotope trends resolução de C, O, Sr e S medidos em amostras bem preservadas e measured in well-preserved sample sets and mainly use Sr and C isotopes usamos principalmente isótopos de Sr e C em consonância com obser- 1NEG-LABISE, Department of Geology, Universidade Federal de Pernambuco – Recife (PE), Brazil. E-mail: [email protected], [email protected], natansp_bio@hotmail. com, [email protected] 2Department of Geology, Facultad de Ciencias – Montevideo, Uruguay. E-mail: [email protected] 3Institute of Geosciences, Universidade Federal da Bahia – Salvador (BA), Brazil. E-mail: [email protected] 4Institute of Geosciences, Universidade de São Paulo – São Paulo (SP), Brazil. E-mail: [email protected] 5Institute of Geosciences, Universidade de Brasília – Brasília (DF), Brazil. E-mail: [email protected], [email protected] 6Companhia de Pesquisa de Recursos Minerais (CPRM) – Salvador (BA), Brazil. E-mail: [email protected] 7Institute of Geosciences and Exact Sciences, Universidade do Estado de São Paulo (Unesp) – Rio Claro (SP), Brazil. E-mail: [email protected] 8Facultad de Ciencias Geológicas, Universidad Mayor de San Andrés – La Paz, Bolivia. E-mail: ferná[email protected] 9Universidade do Estado do Rio de Janeiro – Rio de Janeiro (RJ), Brazil. E-mail: [email protected] 10Centro Universitario Regional del Este, Universidad de la República – Treinta y Tres, Uruguay. E-mail: [email protected] *Corresponding author. Manuscript ID: 20160079. Received in: 06/28/2016. Approved in: 07/28/2016. 439 Brazilian Journal of Geology, 46(3): 439-488, September 2016 Correlations of Neoproterozoic carbonate-dominated in concert with lithostratigraphic/biostratigraphic observations to provide vações litostratigráficas/biostratigráficas, para estabelecer correlações detailed correlations of these successions. The establishing of a high-level detalhadas destas sucessões. Propor uma correlação quimioestratigrá- and definite chemostratigraphic correlation between Neoproterozoic ba- fica entre bacias Neoproterozoicas na América do Sul é o principal sins in South America is the main goal of this work. objetivo deste trabalho. KEYWORDS: Carbonate successions; correlation; isotope chemos- PALAVRAS-CHAVE: Sucessão carbonática; correlação; quimio- tratigraphy; Neoproterozoic; South America. estratigrafia isotópica; Neoproterozoico; América do Sul. INTRODUCTION on Geophysics and Geology (PPPG/UFBA) and Petrobras founded another in 1977, at the Center of Research and The pioneer C-isotope investigation on Paleoproterozoic Development Leopoldo Américo Miguez de Mello (CENPES) carbonate rocks of the Lomagundi province in Africa has in Rio de Janeiro. The widespread use of isotope chemo- evidenced much larger variation of δ13C values (Schidlowski stratigraphy in South America became possible, however, et al. 1983) than previously known from Phanerozoic carbon- only after the installation of a stable isotope laboratory at ate successions (Veizer et al. 1980). This finding has raised the Federal University of Perrnambuco (LABISE) in Recife the possibility that the stratigraphic variation of δ13C val- in 1990 and, later on, in three other Brazilian universities ues could potentially be a tool in stratigraphic correlation. (Brasília, São Paulo, and Pará). Despite widespread effects of late diagenesis on the isotope C- and O-isotope study of Precambrian succes- record, important isotope events could be demonstrated sions in Brazil was first performed by Torquato & Misi on a global scale by means of isotope chemostratigraphy (1977), who also reported a first cap carbonate charac- (e.g. Knoll et al. 1986; Magaritz et al. 1986; Holser 1997, terization (Kaufman et al. 2007). Other pioneer che- to mention a few) as it became evident that contemporane- mostratigraphic investigations in Brazil were performed ous, geographically distant marine strata, registered similar by Torquato (1980), Zaine (1991), Sial et al. (1992), isotopic compositions. Chemostratigraphy serves as one of Chang et al. (1994), Misi & Kyle (1994), Kawashita the principal means of intra- and inter-basinal stratigraphic (1996), Boggiani et al. (1996), Chang (1997), Santos correlation to assemble the Precambrian stratigraphic record et al. (2000, 2004), and Sial et al. (2000). Zaine (1991) from fragments preserved in scattered successions (Karhu has measured C and O isotope ratios in carbonates of et al. 2010). Definitely, chemostratigraphy became an import- the Tamengo Formation, Corumbá Group, and Boggiani ant tool for providing a timeline that compensates for the et al. (1996) have identified an upper Ediacaran positive poor biostratigraphic resolution of Precambrian fossils (e.g. δ13C excursion, associated to the occurrence of Cloudina, Veizer et al.1980; Knoll et al. 1986; Magaritz et al. 1986; which was correlated with the Arroyo del Soldado Group Knoll & Walter 1992; Kaufman et al. 1997, 2007; Corsetti in Uruguay (Gaucher 1999). These studies were followed & Kaufman 2003; Halverson et al. 2005; Sial et al. 2015b). by systematic chemostratigraphic investigations on the Correlations established through chemostratigraphy can be Bambui, Una and Araras groups (Misi & Veizer 1998; used to comment on climate and biogeochemical changes Sial et al. 2000; Santos et al. 2000; Nogueira et al. 2003; through time, although the paucity of radiometric constraints Alvarenga et al. 2004; Misi et al., 2007). Sial et al. (2000), on the absolute age of most of extreme isotope excursions Bekker et al. (2003), and Maheshwari et al. (2010) con- leads, sometimes, to debates on their temporal equivalence firmed the record of the Lomagundi C isotope excursion (e.g. Kaufman et al. 1997; Kennedy et al. 1998; Calver et al. in South America (Iron Quadrangle in Minas Gerais and 2004; Allen & Etienne 2008). In the last three decades, the Paso Severino Formation in Uruguay). Sial et al. (2008) number of studies relying on isotope chemostratigraphy reported, for the first time in South America, the positive has grown substantially and, in the case of C-isotope stra- carbon isotope excursion (SPICE) from the Steptoean at tigraphy, has been applied to metamorphic rocks up to the the Argentine Precordillera and recognized a Sunwaptan high grade (Melezhik et al. 2005; Nascimento et al. 2007; negative carbon isotope excursion (SNICE). Chiglino et al. 2010; Sial et al. 2015a) and may retain dep- An overview on chemostratigraphic correlations of ositional δ13C values in even diagenetically altered carbon- Neoproterozoic carbonate-dominated successions in the ates (Kaufman et al. 2007). South America continent is present here, mainly based on The first stable
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