New radiometric dating of water management features at the prehistoric Purron Dam Complex, Tehuacan Valley, Puebla, Mexico

摘要

Recent investigations at the prehistoric Purron Dam Complex in the Tehuacan Valley of southern Puebla, Mexico applied radiometric dating to more securely date the complex. Ceramic-based dating in the 1960's placed the Dam's origin to the Formative Period. While Formative Period origins are widely accepted, the chronology lacks resolution and direct dates. Samples from impounded sediments behind the dam and from prehistoric canal fill were dated through Optically Stimulated Luminescence (OSL) as well as both standard ~(14)C and accelerated mass spectrometry (AMS) assays. These samples directly date the functioning of the water management features within the complex. The results confirm the Formative Period origins of the Purron Dam, and offer new insights into the construction and functioning of the dam and irrigation system.