Site formation processes of outdoor spaces in tropical environments: A micro-geoarchaeological case study from backyard Lo Gach, southern Vietnam

In the tropics, outdoor areas are important arenas of social life and the scene of economic and daily activities. Yet, outdoor areas are not often detected due to destructive post-depositional processes and low archaeological visibility. Here, we use microarchaeology to establish the settlement history and outdoor use of space at Lo Gach in Long An Province, southern Vietnam. The radiocarbon chronology identifies two phases of occupation: an initial presence at 3300–3000 cal. BP and later activity at 2750–2400 cal. BP. Microarchaeological analysis of the stratigraphy reveals complex sequences of organic waste severely transformed by chemical diagenesis. The results indicate that the excavated area at Lo Gach was an outdoor ‘backyard’ containing external surfaces utilised for a range of activities including rice processing, disposal of combustion residues, in situ burning, and recurrent foot traffic. Intensified rice agriculture and the systematic management of organic waste were the main structuring rhythms of social life that were performed at the Lo Gach settlement.