Fire use and waste management in an Iberian Iron Age village: Geoarchaeological insights into midden formation processes

Middens, commonly found in archaeological sites across different chronologies, serve as rich sedimentary archives of daily life by capturing the refuse and discarded artifacts of past human groups. This study focuses on the midden deposits of the Early Iron Age settlement site of Cerro de San Vicente (Central Iberia). We applied a high-resolution, microcontextual geoarchaeological approach, integrating soil micromorphology —including phytolith and charcoal analyses on thin sections—, sedimentary lipid biomarker analysis, X-Ray fluorescence (XRF), X-Ray diffraction (XRD) and magnetic properties analysis to investigate the formation processes and past functionality of the site’s midden deposits. Our findings reveal that the targeted sequences are primarily composed of wood ash and charred plant refuse, as well as trampled and disintegrated earth-based construction materials. These deposits are interpreted as the result of multiple hearth rake-out events, maintenance and construction activities, and possible spatially-related communal storage practices within the village. Stratigraphic connections between deposits from inside and outside the dwellings are proposed, linking the middens to an intermediate phase (ca. 600 BCE) of the village’s history. These results offer relevant insights into the spatial and temporal dynamics of refuse disposal, maintenance practices and space use at Cerro de San Vicente, highlighting the value of microcontextual geoarchaeological methods in unveiling domestic practices. This study contributes to enhancing our understanding of Early Iron Age socio-cultural and daily life practices in Central Iberia.