Cross section of terraces in the Tonto Basin

Figure 12. Generalized cross section of terraces in the Tonto Basin. At the time of the Salado occupation of the Tonto Basin (1150 to 1450 CE), Pleistocene landforms (e.g., pediments, terraces, and alluvial fans) and Holocene Terrace 3 were the stable elements on the landscape (Waters 1998). Height above the streambed protected these surfaces and associated settlements from flooding. The surface of Holocene Terrace 2 was the most likely location for irrigation agriculture;
investigators have discovered prehistoric canals there.