Fig. 3.

δ¹³C isotope enrichment. Map showing the location of the Perdido Reservoir and its relationship to the pocket bajo to the south/southwest. Sedimentary evidence in the Pocket Bajo (Fig. S5) and unusually high amounts of debris in the Perdido Reservoir indicate that the tank was used for irrigation. Episodes of δ¹³C enrichment in the pocket bajo are compatible with the interpretation of maize agriculture. The base map is from Carr and Hazard (2), courtesy of the University of Pennsylvania Museum of Archaeology and Anthropology.