Morfopedogênese de zona escarpada na alta bacia rio das Velhas, Quadrilátero Ferrífero, MG: análise integrada de dados físicos, químicos e mineralógicos

Resumo

Given the importance of studying the evolution of the soil cover, in continuum, of slopes of escarpment zones, this study aimed to evaluate the pedogeomorphological dynamics of a soil toposequence. The toposequence is located in the Upper Rio das Velhas Basin, Rio das Velhas Supergroup (SGRV), in the southeastern part of Ferriferous Quadrangle (MG). Some soil samples were collected in five selected Cambisols profiles along the toposequence, localized at the upper São Bartolomeu River, subwatershed at the upper Rio das Velhas River. These samples were subjected to mineralogical analysis and physical and chemical analysis. The results showed that the soils are derived from vertical transformation of the SGRV schists, with the lower horizons showing lithodependence. These horizons are separated from the upper colluvium by a stone line, composed of quartz, schist and ferruginous crust fragments and, to a lesser extent, by itabirites. The stone line was of holocen age, a accordingly some OEL datings. It was found out that the soil profiles can be grouped into two large compartments, with different degrees of pedogenetical development. These features suggest that the pedogenetical evolution of the escarpment have been marked by two major morphogenetical erosive phases.

Descrição

Palavras-chave

Topossequência, Toposequence, Cambissolos, Supergrupo Rio das Velhas, Luminescência opticamente estimulada, Cambisols, Optically stimulated luminescence, Rio das Velhas supergroup

Citação

COSTA, Fernanda de Oliveira et al. Morfopedogênese de zona escarpada na alta bacia rio das Velhas, Quadrilátero Ferrífero, MG: análise integrada de dados físicos, químicos e mineralógicos. Geociências, São Paulo, v. 33, n. 3, p. 403-415, 2014.