Estratigrafia, arqueologia e paleoambiente holocênico do Sítio GO-JA-02: uma janela para o passado em Serranópolis (GO)

Abstract

The Holocene is a geological epoch marked by regional climatic oscillations. Unlike previous periods characterized by well-established global events, the Holocene displays complex variations influenced by factors such as seasonal insolation, hydrological dynamics, and altitude. The southwestern region of Goiás, Brazil, stands out as an important site for investigation—particularly the archaeological site GO-JA 02, which preserves a continuous stratigraphic sequence spanning the last 12,000 years. This site represents a valuable window into understanding the interactions between climate, landscape, and human occupation in the Cerrado biome. The research integrates multiple environmental and archaeological proxies, including isotopic analyses (δ¹³C and δ¹⁸O), sediment composition, radiocarbon dating (AMS), and geochemical analyses. The δ¹³C values, ranging from -24.39‰ to -25.69‰ over a depth of 180 cm, indicate the dominance of C₃ vegetation (forests and gallery forests), associated with wetter environments and low influence of C₄ vegetation typical of open and dry savannas. Despite relative isotopic stability, it was possible to identify seven distinct phases in the area's paleoenvironmental evolution. The stratigraphy and geochemical analyses also reveal three phases in the sediment formation process: (1) layers with anthropogenic sediments, associated with human occupation, including evidence of hearths, ash, shells, carbonate layers, and lenses; (2) pedogenized sediments, reflecting post-depositional transformation with input materials; and (3) diagenesis, with evidence of processes such as compaction, leaching, cementation, and dissolution. The evidence shows that global events cannot be considered universal at a local scale, as the Cerrado biome responds differently depending on latitude, altitude, and regional hydrological conditions. Interpreting the Holocene requires integrating global signals with local data, emphasizing the importance of detailed regional studies. The archaeological site GO-JA-02 presents clear divisions for the Holocene period based on archaeological, isotopic, and geochemical data, contributing to the construction of a more robust scenario for the South American Holocene.