The results are presented of the analysis of a set of 116 radiometric dates obtained through the method of Carbon 14 (C14) and thermoluminescence (TL) dating. These datings were taken from nine published studies carried out in the Azapa Valley. Regarding dated samples, these were mostly taken from burials (bodies) and offerings (ceramic) from cemeteries in the Azapa Valley linked to the Middle period. Chronologically this period has been associated with the presence of the Tiwanaku Horizon in the western valleys, 500 to 1000 AD, and its most representative feature is the presence of painted pottery with forms of keros, bowls, pucos and jars. However, the datings obtained for these ceramics mostly correspond to late datings within a range from Cal 900 to 1100 AD. On the other hand, recent information obtained from cemetery Az-115 on new dates indicates that in the first eight centuries of the first millennium of the Christian era there is no Tiwanaku presence in the Azapeño settlement, but rather a type of village continuity linked to a local history with roots in the Formative period.

The present study aims: (a) to characterize the beginnings and development of the Middle period in the Azapa Valley, taking as diagnostic elements the site records of cemeteries Az -115 and Az-75, which present evidence of a local village agricultural process, including evidence related to the Formative period, spanning the Middle period until the eighth century AD; and (b) to define a second stage or phase II of the Middle period in the Azapa Valley, characterized by the consolidation of a local village settlement. In this second phase, the Cabuza, Maitas and Chiribaya styles would characterize the local ceramic styles and would also coexist mainly with styles related to Tiwanaku. Apparently, this is the stage in which local people began to define their own regional identity, whose final expression can be observed in our valleys in what is known as Arica Culture, pottery that characterizes the late Intermediate period (LIP) in the valleys and coast of Arica.