The first record of sedimentary macro-charcoal for the Upper Pleistocene of the Amazon

Abstract

Considered direct evidences of fire, macro-charcoal records in archeological contexts are common for the Amazon and reflect the human arriving in the area at the Pleistocene–Holocene boundary. However, the occurrence of sedimentary macro-charcoal is still rare and unclear in a non-anthropic scenario. This work presents the first record of paleowildfires in the Amazon, expanding paleoenvironmental knowledge about the Upper Pleistocene (∼43,000 years B.P.) paleoenvironments related to the Rio Madeira Formation, Abuña Basin, Rondônia state, Brazil. The samples were extracted from four (4) sedimentary blocks containing leaf compressions previously described for the studied locality. The material was submitted to the standard methods for macro-charcoal studies and charring was confirmed. Although the preserved anatomical features were non-diagnostic for taxonomical affinities (probably angiosperms), the presence of the records in Upper Pleistocene strata 30,000 years previously to the human presence, indicates that the paleowildfire ignition source and spreading was naturally supported by the paleoenvironmental conditions. This first record in the area and interval should serve as incentive to further efforts in the search for more Upper Pleistocene paleowildfire records in the Amazon.