Organic geochemical evaluation of organic acids to assess anthropogenic soil deposits of Central Amazon, Brazil

► Organic geochemical analysis applied to classical archaeological soils of Amazon region for first time. ► Evidence that such analysis is useful for studying tropical archaeological soils. ► Ester bound lipids (alkaline hydrolysis) showed potential for understanding soil organic matter (OM) genesis. ► Different patterns of OM deposition detected for each soil, indicating different sources for OM input.