Microstratigraphy and Site Formation Processes at Quebrada Jaguay 280 (Peru)

ABSTRACT This study presents a microanalytical, geoarchaeological study of Quebrada Jaguay (QJ)‐280, a Terminal Pleistocene–Holocene coastal site in southern Peru. Combining micromorphology, µXRF and µFTIR, we develop a site formation model that also reassesses site use and forager behaviour. Micro‐contextual data provide new insights into sedimentation, taphonomy and human activity, revealing short‐term, seasonal occupations with evidence of spatial shifts in site function and maintenance. Geomorphological observations indicate that the site, originally part of an active alluvial fan, became more stable during times of human occupation. Preservation, however, is compromised by several post‐depositional processes. We observe bioturbation, as well as diagenesis of the faunal and botanical remains by mineral formations, highlighted by the combined contextual application of micromorphology and µXRF mapping. A notable stratigraphic feature, the ‘indurated layer’, is shown to result from salt action. The salt formation is a product of the setting on the arid coast and pedogenic processes, challenging its use as a chronological marker in the areas preserved for our study. Lastly, our findings suggest QJ‐280 functioned as a repeatedly used, short‐term camp within a broader mobility system, contributing new perspectives to early coastal lifeways in western South America.