El volcán Cotopaxi y las primeras ocupaciones del valle interandino de Pichincha, Ecuador: Cambios en el paisaje y geomorfología durante el Holoceno Medio

The Preceramic occupations in the northern Andes of Ecuador, in towns near the city of Quito, have been the result of intense debates regarding their chronology and conservation. The available evidence comes from the “El Inga” site and refers to lithic tools in obsidian, dated to 14 C and a stratigraphy disturbed by erosive processes. This led to the early occupations of this area having a questionable chronology due to the absence of geoarchaeological studies that evaluate the matrix of the archaeological record and the formation process of these sites. However, in the town of Sangolquí, early sites (13,500 – 4,500 BP) could be recorded and excavated, which had a stratigraphy better preserved by ash and lahar deposits from the Cotopaxi volcano. From these data plus a series of analyzes of volcanic ashes, radiocarbon dating and reconstructions of the Early Holocene geomorphology of this area, it has been possible to establish the changes that Cotopaxi volcano generated in the landscape of these sites, going from a relief of small hills to elongated hills that were modeled by lahar deposits around 4.500 BP.