Palinologia e megafauna em sedimentos quaternários da Lagoa do Coronel, Jaguaretama – Ceará, Brasil

Abstract

Palynology and megafauna in Quaternary Lake sediments from Lagoa do Coronel, Jaguaretama – Ceará, Brazil. Numerous natural lakes and tanks function as areas for the accumulation of water and remains of humans and animals in the semiarid regions of the State of Ceará. These sites often hold important proxies (markers) of paleoclimate and vegetation and frequently contain past records of human and fauna presence. Lagoa do Coronel is one of these sites known for previous paleontological finds of Pleistocene megafauna. However, the aridity of the region leads the farmers to search for water in the deepest portions of the dried-up basins at the soil/rock contact, which normally causes stratigraphic disturbance, but put in evidence fossils and artefacts. In February 2021, the excavation of a well in the northern sector of the basin exposed a stratigraphic outcrop, a little more than two meters deep, where the strata intersected with a preserved structure of the deposit. The palynology of the upper horizons of the section suggests higher humidity and milder climate than the present one. Below the sampled horizon, a layer containing megafauna fossils (Xenarthra and Proboscidea) is present, but inaccessible due to the backflow of the water table within the trench. The study of previously recovered fossils is presented here. Keywords: Xenarthra, Proboscidea, pollen, Quaternary Lake sediments, Northeast Brazil.