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@Article{RossettiCTSCMBMTYM:2015:MiPlOS,
               author = "Rossetti, Dilce de F{\'a}tima and Cohen, M. C. L. and Tatumi, S. 
                         H. and Sawakuchi, A . O. and Cremon, {\'E}dipo Henrique and 
                         Mittani, J. C. R. and Bertani, Thiago Castilho and Munita, C. J. 
                         A. S. and Tudela, D. R. G. and Yee, M. and Moya, G.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Federal do Par{\'a} (UFPA)} and {Universidade 
                         Federal de S{\~a}o Paulo (UNIFESP)} and {Universidade de S{\~a}o 
                         Paulo (USP)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {Universidade Federal de S{\~a}o Paulo (UNIFESP)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         de Pesquisas Nucleares} and {Universidade de S{\~a}o Paulo (USP)} 
                         and {Universidade Federal de S{\~a}o Paulo (UNIFESP)} and 
                         {Universidade Federal de S{\~a}o Paulo (UNIFESP)}",
                title = "Mid-Late Pleistocene OSL chronology in western Amazonia and 
                         implications for the transcontinental Amazon pathway",
              journal = "Sedimentary Geology",
                 year = "2015",
               volume = "330",
                pages = "1--15",
                month = "Dec.",
             keywords = "Amazon reversal, Fluvial systems, Mid-Late Pleistocene, OSL ages, 
                         Paleoenvironment.",
             abstract = "The origin of the transcontinental Amazon drainage system remains 
                         unrevealed. Sedimentary deposits formed from the Neogene in the 
                         Amazonas and Solim{\~o}es Basins constitute natural archives for 
                         reconstructing this event in space and time. However, 
                         paleoenvironmental and chronological analyses focusing on these 
                         deposits, or even their basic mapping, are still scarce to allow 
                         such investigation. In this context, primary interests are fluvial 
                         strata related to the lithostratigraphic I{\c{c}}{\'a} 
                         Formation, mapped over a widespread area in western Amazonian 
                         lowlands. Although long regarded as Plio-Pleistocene in age, this 
                         unit has not yet been dated and its overall depositional setting 
                         remains largely undescribed. The main goal of the present work is 
                         to contribute for improving facies analysis and chronology of 
                         these deposits, approaching an area in southwestern Amazonia and 
                         another in northern Amazonia, which are located more than 1000. km 
                         apart. Despite this great distance, the sedimentological and 
                         chronological characteristics of deposits from these two areas are 
                         analogous. Hence, facies analysis revealed paleoenvironments 
                         including active channel, abandoned channel, point bar, crevasse 
                         splay and floodplain, which are altogether compatible with 
                         meandering fluvial systems. Similarly, optically stimulated 
                         luminescence (OSL) dating revealed thirty three ages ranging from 
                         65.4. . 16.9 to 219.6. . 25.1. ky (in addition to three 
                         outliners of 54.0. . 7.6, 337.3. . 36.9 and 346.6. . 48.6. ky), 
                         and nine 97.1. . 9.9 to 254.8. . 23.8. ky for the areas in 
                         southwestern and northern Amazonia, respectively. These data lead 
                         to establish that deposits mapped as I{\c{c}}{\'a} Formation 
                         over a vast area of western Brazilian Amazonia have a Mid-Late 
                         Pleistocene age, rather than the previously inferred 
                         Plio-Pleistocene age. It follows that if Plio-Pleistocene deposits 
                         exist in this region they remain to be dated and must be 
                         restricted to a narrow belt in western Amazonia, as well as 
                         isolated occurrences underlying the Mid-Late Pleistocene strata 
                         characterized herein. The combination of data from this work with 
                         previously published provenance studies supports main Andean 
                         sediment sources only in the Mid-Late Pleistocene. It is proposed 
                         that before this time, the Amazon River was restricted to eastern 
                         Amazonia, being separated from western Amazonian drainage basins 
                         due to the presence of the Purus Arch. Erosion and/or subsidence 
                         of this geological feature would have promoted the connection of 
                         these drainage systems, ultimately with the expressive record of 
                         the transcontinental Amazon pathway into the Atlantic Ocean in the 
                         Mid-Late Pleistocene.",
                  doi = "10.1016/j.sedgeo.2015.10.001",
                  url = "http://dx.doi.org/10.1016/j.sedgeo.2015.10.001",
                 issn = "0037-0738",
             language = "en",
           targetfile = "2015_rossetti.pdf",
        urlaccessdate = "29 nov. 2020"
}


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