Paleoindian Geoarchaeology of the Upper San Pedro Valley, Sonora, Mexico

Abstract

This thesis reports the findings of a multi-disciplinary investigation focused on exploring the Paleoindian habitation of the upper San Pedro Valley, Sonora, Mexico. Two recently-identified fluted points stand as the first Clovis evidence reported from the project area, and site AZ:EE:16:5 (ASM/INAH) has the potential of containing intact Clovis archaeology. Several lanceolate points of the Plainview variety mark the first late Paleoindian evidence reported from Northern Sonora. Four newly identified lithic sources may inform our understanding of Paleoindian range and mobility in the valley and Greater Southwest region. However, intensive geochronological determinations demonstrate that terminal Pleistocene and early Holocene alluvial deposits are rare or absent throughout most of the basin in Mexico. The findings of the project indicate that well-known Paleoindian-age deposits identified at Clovis sites in the valley in Arizona are restricted to relatively small areas of the upper basin north of the border.