Juunkan-1

This is an ironstone Rockshelter that faces south, approximately 25 m wide by 8 m deep, with a dripline (the lip of the shelter) about 8 m high. Features of the site are a higher collapsing chamber at the rear and an entrance area that is open and set at a slightly lower level and the 2 areas are separated by a lot of roof fall. The rear chamber has a floor that consists of soft sediment sloping down from the rear. Along the front of the site flaked stone material has been found, particularly in the western end of the shelter.

The first excavation at this site was a 1 x 1 m test pit in 2008 in the front chamber of the Rockshelter. At 75 cm below the surface a solid roof fall or bedrock was encountered. There were 3 main layers that comprised the stratigraphy of the test pit: a topsoil of loose material above brown/grey sediment that was compacted containing many organic finds and below this a horizon of orange/brown material. At a depth of 40-50 cm there was a small lens of pink/white soft chalky material, and at the same depth were small charcoal lenses.

The results of 3 radiocarbon determinations show that the earliest evidence of discard at Juunkan-1 indicated that discard was occurring at a conventional radiocarbon date of 32,950 ± 270 BP (Beta 249759) at a depth of 60 cm. The accumulation of sediment and the discard of artefacts were very slow until a depth of 35 cm below the surface, which has been dated to 26,640 ± 160 BP (conventional radiocarbon age) (Beta-249758). From 35 cm below the surface it is proposed there was a generally more rapid rate of accumulation that extended to more recent times near the surface that has been dated to 760 ± 40 BP (conventional radiocarbon age) (Beta-249757) (740-760 ca. yr. BP).

From Juunkan-1 the total number of stone artefacts recovered was 32. Spits 1 and 2 (a spit is a unit of excavation in archaeology) contained the majority of these, and with only individual artefacts being recovered from lower spits. The oldest artefact recovered from this site was in spit 14, which was 70 cm deep, and below the layer that has been dated to 32,920 BP. All the flaked stone was recovered from the far southeastern corner of the test square. Slack et al. (2009) suggest it is likely that a greater assemblage size will be found with further planned extensions to the excavations.

As well as flaked stone there were 67 fragments of animal bone recovered from this site, 57 of which were identifiable. Among the species identified were bandicoot, kangaroo, wallaroo, native mouse, rat and 1 fragment of fish. With the exception of spit 9, animal bone from small to large species were recovered from most spits, with majority of bone being from medium-large species of macropod. The density of faunal remains is consistently small, apart from spit 12, where almost 50 % of the bone was found. All of the bone is highly fragmented and fragments of long bones accounting for 66 % of the bone that was recovered, followed by teeth (9 %).

A total of 9 bone fragments had been burned, of which 2 are calcined, which suggested they had been deposited in fire for longer periods of time. In addition to burning, taphonomic analyses have shown several specimens to have evidence of heavy mineralisation, which is potentially suggestive of greater time depth. The bone that has been recovered from Juunkan-1 unweathered, and has no post-depositional modifications on the surface that are obvious, which suggests an in situ deposition and rapid burial.

Activity of either humans or carnivores is suggested by the frequency of fragments of long bone shafts among the faunal assemblage. This assemblage is believed to have most likely been accumulated by humans as there are no animal gnaw marks on the surviving bones, together with evidence of burning from fire. It is difficult to draw conclusions concerning species utilisation changes and/or frequency diachronically. The extant faunal evidence, however, suggests both species and element frequencies remained constant throughout the spits that contained bone, showing no evidence of diachronic change. Also, spit 12, which associated with the oldest date (and possibly) with the oldest artefact, and it provides clearer evidence of early occupation.

Sources & Further reading

1. Slack, M., M. Fillios and R. Fullagar (2009). "Aboriginal Settlement during the LGM at Brockman, Pilbara Region, Western Australia." Archaeology in Oceania 44(S1): 32-39.