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@Article{RossettiGˇes:2009:MaInBa,
               author = "Rossetti, Dilce de F{\'a}tima and G{\'o}es, Ana Maria",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         Universidade de S{\~a}o Paulo, USP, Instituto de 
                         Geoci{\^e}ncias, Programa de P{\'o}s-Gradua{\c{c}}{\~a}o em 
                         Geoqu{\'{\i}}mica e Geotect{\^o}nica Rua do Lago, 562, 
                         Butant{\~a}, 05508-080 S{\~a}o Paulo, SP, Brasil",
                title = "Marine influence in the barreiras formation, state of alagoas, 
                         northeastern brazil",
              journal = "Anais da Academia Brasileira de Ci{\^e}ncias",
                 year = "2009",
               volume = "81",
               number = "4",
                pages = "741--755",
                month = "Dec.",
             keywords = "Miocene, marine transgression, tidal currents, sedimentary 
                         structures, northeastern Brazil, Mioceno, transgress{\~a}o 
                         marinha, correntes de mar{\'e}, estruturas sedimentares, nordeste 
                         do Brasil.",
             abstract = "Tidal processes were important for deposition of the Barreiras 
                         Formation located in northern Brazil, while correlatable deposits 
                         in northeastern Brazil have been traditionally related to 
                         continental environments. Facies analysis in southern Alagoas 
                         revealed that the Barreiras Formation consists of cross-stratified 
                         conglomerates and sandstones (facies Sx and Cgx), compound 
                         cross-stratified sandstones (facies Cx), and heterolithic beddings 
                         (facies H). A significant portion of these deposits occurs within 
                         channel morphologies displaying fining and thinning upward 
                         successions. An abundance of sedimentary features is comparable to 
                         those from the northern Brazilian counterpart. These include: 
                         tidal bundles; herringbone cross-stratification; heterolithic 
                         beddings with sandstone and mudstone beds in sharp contacts; and 
                         ichnofossils mostly consisting of Ophiomorpha nodosa, Skolithos 
                         and Planolites. Altogether, these features point to a marginal 
                         marine depositional setting dominated by tidal processes, which 
                         are related to an estuarine system, an interpretation also 
                         provided for the Barreiras Formation in northern Brazil. The 
                         widespread occurrence of deposits with unambiguous evidence of 
                         tidal processes in the Barreiras Formation of northern Brazil, and 
                         now in the State of Alagoas, leads to argue that the early/middle 
                         Miocene worldwide marine transgression might have left a much more 
                         widespread sedimentary record along the Brazilian coast than 
                         currently regarded. RESUMO: Processos de mar{\'e} foram 
                         importantes na deposi{\c{c}}{\~a}o da Forma{\c{c}}{\~a}o 
                         Barreiras localizada no norte do Brasil, enquanto dep{\'o}sitos 
                         correlatos do nordeste brasileiro t{\^e}m sido tradicionalmente 
                         relacionados a ambientes continentais. An{\'a}lise de f{\'a}cies 
                         no sul de Alagoas revelou que a Forma{\c{c}}{\~a}o Barreiras 
                         consiste em conglomerados e arenitos com 
                         estratifica{\c{c}}{\~o}es cruzadas (facies Sx e Cgx), arenitos 
                         com estratifica{\c{c}}{\~a}o cruzada composta (facies Cx), e 
                         acamamentos heterol{\'{\i}}ticos (facies H). Uma 
                         por{\c{c}}{\~a}o significativa desses dep{\'o}sitos ocorre 
                         inserida em morfologias de canal, internamente contendo 
                         sucess{\~o}es de granocresc{\^e}ncia e adelga{\c{c}}amento 
                         ascendentes. A abund{\^a}ncia de fei{\c{c}}{\~o}es 
                         sedi-mentares {\'e} compar{\'a}vel {\`a}quelas documentadas em 
                         dep{\'o}sitos correlatos do norte do Brasil. Estas incluem: 
                         bandamentos de mar{\'e}; estratifica{\c{c}}{\~o}es cruzadas 
                         espinha-de-peixe; acamamen-tos heterol{\'{\i}}ticos contendo 
                         camadas de arenitos e argilitos em contato brusco; e 
                         icnof{\'o}sseis consistindo principalmente em Ophiomorpha nodosa, 
                         Skolithos e Planolites. Estas fei{\c{c}}{\~o}es apontam para 
                         ambiente deposicional marinho marginal dominado por processos de 
                         mar{\'e}, possivelmente relacionado a sistema estuarino. Esta 
                         interpreta{\c{c}}{\~a}o {\'e} similar {\`a} atribu{\'{\i}}da 
                         para a Forma{\c{c}}{\~a}o Barreiras no norte do Brasil. A ampla 
                         ocorr{\^e}ncia de dep{\'o}sitos contendo evid{\^e}ncia 
                         inequ{\'{\i}}voca de processos de mar{\'e} na 
                         Forma{\c{c}}{\~a}o Barreiras no norte do Brasil, e agora 
                         tamb{\'e}m no Estado de Alagoas, leva a propor que o 
                         per{\'{\i}}odo de transgress{\~a}o marinha registrada 
                         globalmente no eo/meso Mioceno pode ter deixado um registro 
                         sedimentar muito mais amplo ao longo da costa brasileira do que 
                         at{\'e} ent{\~a}o considerado.",
                  doi = "10.1590/S0001-37652009000400012",
                  url = "http://dx.doi.org/10.1590/S0001-37652009000400012",
                 issn = "0001-3765",
                label = "lattes: 0307721738107549 1 RossettiG{\'o}es:2009:MAINBA",
             language = "en",
        urlaccessdate = "27 jan. 2021"
}


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