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STRATI 2013 pp 481-485 | Cite as

Environmental Reconstruction of the South-Western Part of the Maracujá River Basin, Brazil, Based on Palynological and Sedimentological Analysis and Carbonaceous-Layer Radiocarbon Dating

  • Maria Paula DelicioEmail author
  • João Paulo Marques Machado Teixeira
  • Makênia Oliveira Soares  Gomes
  • Maria de Fátima Rodrigues Sarkis
Conference paper
Part of the Springer Geology book series (SPRINGERGEOL)

Abstract

We used sedimentological, palynological, and stratigraphic analysis, as well as absolute dating of a carbonaceous layer, to characterize Quaternary sediments deposited in the south-western part of the Maracujá River Basin located in the Quadrilátero Ferrífero geological province (Minas Gerais state, Brazil). Based on the sedimentology at an outcrop section, we defined four facies and nine subfacies that depict energy pulse variations, reflecting distinct palaeoenvironmental conditions and transitions. Palynological assemblages through the section verify inferred climate changes. Radiocarbon dating of samples from the lowest, middle, and highest stratigraphic layers revealed ages of 4730 ± 40  yr BP, 12730 ± 50  yr BP, and 16260 ± 70 yr BP, respectively. The geochronological data reveal that older layers lie above younger layers, showing a reversed temporal sequence in the area. This was a result of the sediments having developed in a flood plain environment; subsequent gully-erosion processes in the region left a sequence of alluvial terrace deposits on the peripheries of the flood plains.

Keywords

Dating climate changes Stratigraphic reversal Quaternary Brazil 

References

  1. Gomes, M. O. S. (2008). Caracterização Palinológica dos Sedimentos do Quaternário da Bacia do Rio MaracujáOuro Preto (p. 123). Departamento de Geologia, Universidade Federal de Ouro Preto, MsC Dissertação de Mestrado.Google Scholar
  2. Salgado-Labouriau, M. L. (Ed.) (1994). Historia ecológica da Terra (2nd ed., p. 307). São Paulo: Ed. Edgard Blucher LTDA.Google Scholar
  3. Suguio, K. (Ed.) (2010). Geologia do Quaternário e mudanças climáticas (2nd ed., p. 408). São Paulo: Ed. Oficina de Textos.Google Scholar
  4. Wentworth, C. K. (1922). A scale of grade and class terms for clastic sediments. Journal of Geology,30, 377–392.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Maria Paula Delicio
    • 1
    Email author
  • João Paulo Marques Machado Teixeira
    • 1
  • Makênia Oliveira Soares  Gomes
    • 2
  • Maria de Fátima Rodrigues Sarkis
    • 3
  1. 1.Department of Geologic Engineering, Mines SchoolFederal University of Ouro Preto—DEGEO/EM/UFOPOuro PretoBrazil
  2. 2.Geosciences Institute, Geology Post-graduation ProgramFederal University of Minas Gerais—IG/UFMGBelo HorizonteBrazil
  3. 3.Institute of Science and TechnologyFederal University of Alfenas. ICT/UNIFAL-MGAlfenasBrazil

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