The Huaca Grande is a large mound extending over 176 m long and 73 m wide by 7-8 m high, located in the Sechura Desert (north of Peru), about 300 m from the Pacific Ocean. Excavated in the 1970s (Cardenas et al., 1991), then between 2015 and 2017 by the Sechura Desert Archaeological Project, the site provided a thick stratigraphic succession of approximately 2.8 m, consisting of alternating hearths, layers of shells and remains of fish interstratified with sterile sandy levels. In addition, a clay wall, possibly a remnant of a structure, and several post holes were discovered at a depth of 2.2 m. Eight absolute dates were run along the sequence, which covers more than a thousand years of local history, between cal. AD 399 and 1447.
Given its richness and variety, the sequence has been the subject of a high-resolution multidisciplinary study (micromorphology, sedimentology, malacology, marine mammals, ichthyology, anthracology and plant macrorests). The results of sedimentological and micromorphological analyses allowed us to determine the composition and nature of the various stratigraphic units that make up the sequence, and to identify the natural processes and anthropogenic actions and activities that led to their deposition. We were thus able to reconstruct the history of the site and its evolution over time, firstly stating that it is not a continuous occupation and that some abandonment phases have been recorded. Biomarker studies have enriched this reconstruction by providing detailed information not only on the use of natural resources by the inhabitants of the site but also, indirectly, on the environmental contexts contemporaneous with the pre-Hispanic human occupation.
This multidisciplinary approach, carried out on a diachronic scale that is still unexplored in the region, coupled with the study of structures and archaeological remains, has provided an insight into the modalities of human occupation of the Sechura Desert between the AD 5th and 15th centuries.