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@Article{MirandaRossRuiz:2009:FaDeC1,
               author = "Miranda, Maria Carolina Da Cruz and Rossetti, Dilce De Fatima and 
                         Ruiz Pessenda, Luiz Carlos",
          affiliation = "Universidade de S{\~a}o Paulo-USP, Instituto de Geoci{\^e}ncias, 
                         Rua do Lago, 562, 05508-080 S{\~a}o Paulo, SP, Brazil and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         Universidade de S{\~a}o Paulo, Laborat{\'o}rio de 14C, Avenida 
                         Centen{\'a}rio 303, 13416000 Piracicaba, SP  Brazil",
                title = "Quaternary paleoenvironments and relative sea-level changes in 
                         Marajo Island (Northern Brazil): Facies, delta C-13, delta N-15 
                         and C/N",
              journal = "Palaeogeography, Palaeoclimatology, Palaeoecology",
                 year = "2009",
               volume = "282",
               number = "1",
                pages = "19--31",
                month = "Nov",
             keywords = "Sedimentary facies, Carbon and nitrogen isotopes, Relative sea 
                         level, Tectonics, Estuary, Late Quaternary, nitrogen isotope 
                         composition, georgia salt-marsh, organic-matter, carbon-isotope, 
                         stable carbon, environmental-changes, early diagenesis, estuary, 
                         ratios, sediments.",
             abstract = "The reconstruction of physical environments of Amazonian areas is 
                         of great interest to determine the dynamic evolution of the Amazon 
                         drainage basin. However. few studies have emphasized the 
                         Quaternary deposits in this region. which is mostly due to the 
                         lack of natural exposures imposed by the low topography. This work 
                         integrates facies analysis. radiocarbon dating, delta C-13, delta 
                         N-15, and C/N of an 124 m-thick core from an area located at the 
                         mouth of the Amazon River. northeastern Amazonia. The study 
                         records deposits up to 50.795 C-14 yr B P. in age. which formed in 
                         a variety of depositional environments including fluvial channel, 
                         tidal flat, outer estuarine basin to shallow marine. inner 
                         estuarine basin, estuarine channel and lagoon. Facies 
                         interpretation was significantly improved with the inclusion of 
                         delta C-13, delta N-15, and C/N analyses of organic matter 
                         extracted from the sediments The obtained values conform to a 
                         transitional. mostly estuarine paleosetting evolved during 
                         successive relative sea-level fluctuations. The results suggest 
                         fluvial deposition between 40,950 (+/- 590) and 50.795 C-14 yr B 
                         P, with a rise in relative sea level that commenced between 35,567 
                         (+/- 649) and 39,079 (+/- 1114) C-14 yr B P. An overall 
                         transgression took place until 29,340 (+/- 340) C-14 yr B P., 
                         after which the relative sea level dropped, favoring valley 
                         rejuvenation and incision. Following this time up to 10,479 (+/- 
                         34) C-14 yr B.P. a rise in relative sea level filled up the valley 
                         with estuarine deposits After 10.479(+/- 34) C-14 yr B.P., the 
                         estuary was replaced by a lagoon At the end of the Holocene, the 
                         coastline prograided approximately 45 km northward, replaci ng the 
                         lagoon by a lake system Despite the influence of eustatic 
                         fluctuations. regional tectonics played a significant role to 
                         create new space where these Late Pleistocene and Holocene 
                         sediments accumulated. (C) 2009 Elsevier B V All rights 
                         reserved.",
                  doi = "10.1016/j.palaeo.2009.08.004",
                  url = "http://dx.doi.org/10.1016/j.palaeo.2009.08.004",
                 issn = "0031-0182",
             language = "en",
           targetfile = "miranda.pdf",
                  url = "10.1016/j.palaeo.2009.08.004",
        urlaccessdate = "18 jan. 2021"
}


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