Hierarchies of engagement and understanding: Community engagement during archaeological excavations at Khao Toh Chong rockshelter, Krabi, Thailand

Abstract

Khao Toh Chong (KTC) rockshelter was first recognized as an archaeological resource by two local school teachers who bought it to the attention of the Thai Fine Arts Department, who led Ben Marwick to the site. The site is a limestone overhang at the base of a 300m high karst tower in Thap Prik Village. The rockshelter is about 30 m long with an average of about 10 m from the rear wall to the dripline. The dripline is about 40 m above the ground and a series of large boulders (3-4 m high) at the dripline give excellent protection from the wind and rain as well as trapping sediment in the shelter. The surface of the rockshelter is level fine sediment with no signs of disturbance and about 10 m above the surrounding ground, which is about 60 m above sea level. KTC has a deep multi-chambered cave system with well-preserved active speleothem formations located about 30 m to the west of the rockshelter. In June-July 2011 we directed a four week archaeological field school at KTC that included students from Thailand, Cambodia, Indonesia, Burma, the Philippines, Korea, Vietnam and the US. The field school excavated two areas of 2 x 2 m to a depth of about 2 m and recorded unusually well preserved stratigraphic layers and features, including shellfish lenses. Analysis of these materials is ongoing, and our initial impressions are that the excavated deposit spans the entire Holocene period and early Pleistocene. There are several distinct changes in the sequence in each of the major categories of evidence we recovered. The stone artefact technology changed from polished adze flakes made from fine grained sedimentary rock accompanied by ceramics in the upper levels to large flaked cores and flakes made from coarse grain metamorphic rock in the lower levels. The lower levels also show a change in the faunal assemblage with the appearance of artiodactyl remains (some with cut marks) and a reduction in the remains of small mammals and reptiles that are common in the upper parts of the site. The ceramic assemblage also changes from black sherds in the upper levels to thicker, red sherds with frequent incised decorations in the lower levels and then ceramics disappear altogether when flaked cores and artiodactyl remains appear in the lowest levels. We interpret the lower levels, with their artiodactyl remains, flaked stone artefacts and absence of ceramics and polished stone artefacts, as likely to have been deposited during the Pleistocene and expect radiocarbon analyses to confirm this. One of the features of this deposit that makes it unique amongst mainland Southeast Asian sites is that relatively few post depositional processes have disturbed the site. For example there we did not encounter any burials, no animal burrows and there is very limited termite activity at this site. The most striking indication of this is a series of dense shell dense 0.1 m thick that vary in the proportion of species from the upper levels to the lower levels. With further analysis we expect the taxonomic variation in these shell layers will yield information about environmental change and human adaptive responses during the Holocene.