ANÁLISE DAS CARACTERÍSTICAS PEDOESTRATIGRÁFICAS DA PLANÍCIE DO PANTANAL ENTRE OS RIOS VERMELHO E ABOBRAL, MS-BRASIL

Abstract

The Pantanal is considered an area of plain or humid land that undergoes extensive seasonal flooding processes. It is an area with a complex system of sediment transport and deposition. Pedostratigraphy allows to reconstruct events and processes that allow us to understand and reflect on the tectonic and depositional history of the basin and its adjacent areas. The objective of this work is to present the results of the study on the pedostratigraphy of the Pantanal plain between the Vermelho and Abobral rivers. The study sites were chosen according to the relief forms presented, higher, non-floodable and with arboreal vegetation (mountain ranges) and others that are part of the seasonally floodplain with only undergrowth. The samples were collected in tubes, a total of six samples, three in higher areas and three in the plain. In the laboratory, the identification of the colors was performed using the Munsel table and the granulometry using sieving for the separation of the grains. As for coloration, the predominant hue in all samples was 10YR, varying only the values and chroma. In the mottled ones, there was also a predominance of 10YR matrix, varying only the values and chroma. In the particle size analysis, there was a predominance of fine and very fine sand types. The samples also indicate a significant presence of silt and clay. The particle size fractions are very close to those found in the Nhecolândia wetland. The theories about the formation of the relief of Nhecolândia are associated with a more arid past and, therefore, this being a dune field. That said, it opens up the perspectives of thinking about the origin of the material deposited in this area of study and allowed to glimpse a possible field of dunes with even greater proportions.