The Eastern Plaza
In the Eastern Plaza, we set up two excavation units (8 m2), with the intention of identifying major activity areas. We detected two main occupational episodes. The Early Inka occupation consisted of an extensive midden deposited over the sterile matrix. The ceramic density was high, and the assemblage was similar in composition to the Western Plaza’s early midden. That is, utilitarian ceramics were common, and the most popular decorated ceramic types encompassed local Manchachi Slate on Red wares, followed by the Condorillo Crushed Sherds style from the eastern tropics. A calibrated AMS C-14 analysis revealed that this midden was deposited around A.D. 1412-1434, at one sigma error (68 percent of confidence) (Figure 5.6, Table 5.1; sample AA36941).
By comparison, the Late Inka occupation in the Eastern Plaza was represented by the deposition of an artificial thick yellow clay matrix on top of the earlier refuse. Very few artifact remains were identified in association with this renovation floor. In fact, this layer was used to architecturally renovate the whole plaza, as well as other areas of the complex. Hence, the function of this courtyard changed abruptly during this second period. From being a public space of intensive use, in the second period it was less intensively used. Afterward, the area was abandoned.
Comparing the chronological sequences of the two plazas brings up interesting issues related to their construction and use history. Each starts with an early midden characterized by the abundance of the local Man- chachi Slate on Red ceramics, stylistically associated with western valley polities. After the abandonment of the early ushnu platform, the Western Plaza was covered with a second trash layer with a dominance of Guarani and eastern-tropic ceramics. By contrast, in the Eastern Plaza the deposition of a yellow clay layer on top of the early midden marked the last occupational episode. Therefore, whereas the Eastern Plaza in this last period became a more restricted and private area, the Western Plaza was the locus for public activities involving Guarani-related pottery.