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@InProceedings{RossettiBGVAMTB:2010:LaPlRe,
               author = "Rossetti, D and Bezerra, F H and G{\'o}es, A and Valeriano, M and 
                         Andrades Filho, C and Millani, J and Tatumi, S and Brito Neves, B 
                         B",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {} and USP, 
                         S{\~a}o Paulo, Brazil and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and FATEC, S{\~a}o Paulo, Brazil and FATEC, S{\~a}o 
                         Paulo, Brazil and USP, S{\~a}o Paulo, Brazil",
                title = "The late Pleistocene-Holocene record of sea level in Northeastern 
                         Brazil and its relation to climate, eustasy and tectonics",
            booktitle = "Proceedings...",
                 year = "2010",
         organization = "Meeting of the Americas.",
             abstract = "AB: Late Quaternary deposits in Northeastern Brazil have been 
                         scarcely investigated, despite their great relevance to discuss 
                         the post-rift evolution of South American passive margin within 
                         the context of landform, sea level and tectonic deformation. 
                         Sedimentological, stratigraphic and morphological characterization 
                         of these deposits led to their distinction from the underlying 
                         Early/Middle Miocene Barreiras Formation. Two sedimentary units 
                         (PB1 and PB2) were recognized and related, with basis on optically 
                         stimulated luminescence (OSL) dating, to the time intervals 
                         between 74.89.3 and 30.86.9 ka, and 8.80.9 and 1.80.2 ka, 
                         respectively. Unit PB1 is exposed discontinuously in the highest 
                         topography (usually between 100 m and 150 m), being mostly 
                         composed of endured sandstones and breccias either with massive 
                         bedding or an abundance of complex styles of ductile and brittle 
                         soft sediment deformation structures related to contemporaneous 
                         seismic activity. This unit also includes a large volume of 
                         non-indured sharply bounded, fining upward massive or stratified 
                         conglomerates and sandstones interbedded with mudstones, 
                         attributed to fluvial, alluvial and aeolian dune environments. 
                         These deposits might include nearshore marine-influenced strata in 
                         areas located nearby the modern coastline, as suggested by 
                         presence of burrows as Skolithos, Thalassinoides, Planolites, 
                         Diplocraterion, and Teichichnus. Unit PB2, composed of sands with 
                         massive or dissipation dune structures, occurs continuously, 
                         mostly on northeastward dipping tablelands located at altitudes 
                         lower than 100 m. The present work focusing on units PB1 and PB2, 
                         together referred as Post-Barreiras Sediments, opens a new 
                         opportunity to discuss landform, sea level and tectonic history of 
                         eastern South American passive margin during the latest 
                         Quaternary. Hence, following the Miocene transgression, there was 
                         a prolonged period of non-deposition and sub-aerial exposure, 
                         which is related to combination of a worldwide low sea level in 
                         the Tortonian and tectonic quiescence. Sediment deposition was 
                         reactivated during the latest Pleistocene due to tectonic 
                         deformation, which created space to accommodate unit PB1 in 
                         downthrown faulted blocks and, perhaps, also synclines produced by 
                         extension and compression associated with strike-slip tectonic 
                         deformation. Although deposition of this unit was simultaneous to 
                         the eustatic fall that followed the Penultimate Transgression, 
                         punctuated rises superimposed on the overall fall, added to 
                         subsidence, would have favored marine deposition in areas located 
                         nearby the modern coastline. A renewed phase of deformation would 
                         have resulted in newly subsiding areas in the Holocene, promoting 
                         deposition of unit PB2 over unit PB1. Although unit PB2 formed 
                         during most of the last transgression, except along coastal areas, 
                         it has no records of marine sedimentation, suggesting a 
                         non-significant rise or reworking of thin transgressive sands by 
                         aeolian process. The data presented herein leads to review the 
                         evolution of South American passive margin based on assumptions of 
                         uniform sedimentation and undeformed planation surfaces over a 
                         wide coastal area of Northeastern Brazil.",
  conference-location = "Foz Igua{\c{c}}u",
      conference-year = "8-12 Aug. 2010",
             language = "en",
           targetfile = "cintra.pdf",
        urlaccessdate = "22 jan. 2021"
}


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