CHRONOLOGY OF QUARTZITIC SLOPES FROM MINAS GERAIS, BRAZIL

• DOI: 10.4215/rm2022.e21032
• Publication Date: 2023-02-19T14:12:46Z
• Authors: Silvio Carlos Rod...; Fabiana Cristina ...; Rui Filipe Ferrei...; Thallita Isabela ...
• Keywords: Colluvium; Chronology; Saprolite; Geochronology; Denudation; Radiometric dating

Quartzitic mountain reliefs developed in a tropical savanna climate tend to have shallow sedimentary deposits. This is due low level weathering processes of quartzite rocks and formation colluvium ramps on the slopes. study aims determine characteristics colluvial materials, particularly grain size, analyze sediment chronology above saprolite, seeking identify accumulation rates make correlations with dynamics recent geomorphological evolution Canastra range Minas Gerais, Brazil. Samples collected different morphological positions were submitted granulometric analysis dated by Optically Stimulated Luminescence Single Aliquote Regeneration (OSL/SAR) radiocarbon dating. Grain size showed predominance sandy gravel materials demonstrated that area contain derived from decomposition rocks, accumulated profiles. LOE/SAR dating indicated ages between end Pleistocene, not exceeding 30,500 +/- 4,950 BP, 500 years whereas 14C 4460 30 BP 1140 BP. These data indicate deposits are relatively recent, which demonstrate variations process deposit undergone changes, probably climatic fluctuations changes regional hydrological regime. Keywords: Range, Paleogeomorphological Reconstruction, Weathering Quartzites, OSL, Tropical Range