Paleoindian sites in eastern South America are generally found inside rock‐shelters. Recently, we designed a program to find open‐air Paleoindian sites in the Lagoa Santa region of Brazil. Here, we present data gathered at Sumidouro site, a multicomponent site with a Paleoindian horizon, detected on a shoreline slope of Sumidouro Lake, Minas Gerais State. We present a model for late Pleistocene/Holocene slope evolution that suggests at least three different episodes of instability (erosion/sedimentation) followed by periods of stability (pedogenesis). Higher soil accretion rates during the Mid‐Holocene are probably not linked to a stable dry climate, but to greater climatic instability. We also found that the position of both archaeological materials and charcoal can be explained by burial of ancient surfaces and are not the result of downslope movement. The role of bioturbation in the vertical displacement of such materials is much less important than previously acknowledged.

Lagoa do Camargo 1, a Paleoindian archaeological site located in southeast Brazil dated between 10.5 and 8.3 ka, was studied using a variety of analyses: artifact and charcoal frequencies, soil morphology and micromorphology, magnetic analysis, optically stimulated luminescence, and radiocarbon dating. Our results show that the sandy tropical Oxisol present at the site was accumulated by episodic erosion and accumulation of materials along the slope, by means of diffuse runoff (sheet wash), and that bioturbation, albeit present, played a minor role in the soil formation. From a geoarchaeological point of view, the site poses an important problem, which is the presence of a deeply buried archaeological site almost at the top of a plateau. Our conclusions are relevant for understanding the genesis of sandy Oxisols that cover a large portion of southeast Brazil, where charcoal fragments are abundant, and whose genesis is considered by some authors to be strongly related to pedoturbation.

Resumo:O presente estudo tratou das feições doliniformes na bacia do alto rio Preto. De um total de 177 feições identifi cadas, a maioria está próxima ou conectada à drenagem, sendo menos circulares que outras identifi cadas como isoladas. Tais feições possuem agrupamentos nítidos e sua distribuição indica que são controladas por falhas associadas a dobras da Faixa de Dobramentos Brasília, diante da comparação de seus eixos de orientação com alinhamentos geológicos. Foi observado que 90% das depressões se assentam sobre as rochas carbonáticas do Grupo Bambuí. Abstract:This paper presents the doline-like forms in the Upper rio Preto basin. From a total of 177 identifi ed features, most are next or connected to the drainage, but it are less circular than other identifi ed as isolated. Such features have crisp clusters and indicate a control by fault folds from The Brasília Mobile Belt, on comparing the axes with geological alignments. It is important to consider that 90% of depressions occur on carbonated lithology's of the Bambuí Group.

This paper presents the depressions in the Upper Rio Preto basin. From a total of 177 identified features, most are connected to drain, but is less circular than other identified as isolated. Such features have crisp clusters and indicate be controlled by fault folds from Faixa de Dobramentos Brasília, on comparing the axes with geological alignments. It is important to consider that 90% of depressions dwell on the Group Bambuí, but can not say whether by dissolving its rocks or by dissolving covers.