Jinmium Rockshelter

Australia: The Land Where Time Began

Jinmium Rockshelter, Northern Territory

The age of this site has been very controversial, the earliest dates not being accepted by most scientists.

In the Unit 1, lowest stratigraphical level, there were multi-platform quartzite cores, flakes, fragments, unifacially retouched flakes, and quartzite cobbles that had been used as pounding stones that still has starch residue on the working surfaces. (Fullagar et al., 1996).

A series of TL dates on quartz, 116,000* +/- 12,000 to 73,300 +/- 7,000. These are the earliest dates recorded for ochre. For a buried sandstone slab that has pecked cupules the earliest date is 58,000 +/- 6,900 BP & 75,000 +/- 7,000. All these dates are very controversial and are not accepted as accurate. Fullagar et a., (1996); sf, Roberts et al.,(1998); Watchman et al., (2001). 7 AMS dates on charcoal from the upper 2/3 of the deposit at Jinmium ranged from 1,1100 +/- 60 BP to 3,300 +/- 100 BP. A series of OSL dates from individual quartz grains from the deposit ranged from 300 +/- 30 BP to 22,000 +/- 1,200 BP. (Roberts et al., 1998). Among 16 AMS dates on oxalate in the crust covering cupules were 1,400 +/- 110 BP, and from 5,840 +/- 65 BP to 11,050 +/- 650 BP. The 11,000 BP date is considered inconsistent because the disparity "between the thickness of the crust and its age when compared with the other crusts in the Keep River region" (Watchman et al., 2000: 7). Watchman (2000); Watchman (2001).

Jinmium Rock Shelter, Northern Territory – Early Occupation of Northern Australia by Humans⁴

The Jinmium Rock Shelter is an archaeological site field code: Coornamu 1 or ‘C1’, NTMAG site number: 4767 0028) (129.2^oE, 15.4^oS) is located within 50 km of the mouth of the Keep River, in the northwestern corner of the Northern Territory.

The study area

This site that was excavated by Fullagar, Price and Head is situated on undulating sands gently sloping towards Coornamu Swamp and Sandy Creek, east of the Kimberley region between the Ord River and Victoria River. The region between the Ord River and the Victoria River is semiarid, with a warm, dry monsoonal climate that is characterised by a distinct wet season that occurs between December and April, and has an annual rainfall of 700-900 mm. The maximum daily temperature ranges from about 30^oC to 35^oC and a minimum between 20^oC and 25^oC (Stewart et al., 1970).

The area of the Keep River is located within the Ord-Victoria geomorphic region, and is part of the Bonaparte Basin, and is younger than, and lies between, the Kimberley Basin to the west and the Victoria Basin to the east (Whitehead & Fahey, 1985). The area consists of estuarine deltaic plains, open woodlands and tall grass plains, with rugged sandstone hills and low hilly country. The 2 main stream systems in the area are the Keep River and Sandy Creek, both of which flow to the north into the Joseph Bonaparte Gulf. Included in 4 main Palaeozoic units are dolomites from the Lower Carboniferous (Burt Range Formation) and sandstone and conglomerate dating to the Upper Carboniferous, the Border Creek Formation, in which the Jinmium Rock Shelter formed. Surface occurrences on the Burt Range Formation include cryptocrystalline silica that is suitable for flaking, including cherts, silcrete and chalcedony. Quartz and quartzite are suitable for flaking, and several locations of prehistoric quarries have been documented by Fullagar, Price and Head.

The establishment of cattle stations in the Kimberley region on the 1880s marks the onset of European settlement history. Between 1909 and 1019 Legume Station began as an outstation of Carlton Hill. Stories that were documented (Shaw, 1981, 1986) indicate the Legume was an important location for Aboriginal law and the relations to land that were maintained throughout the pastoral period (see also Head, 1994b).

Archaeological work in the Kimberley and the Victoria River District that was previously reported suggests there were 2 distinct technological phases based on analyses of stone artefacts and an antiquity of at least 40,000 years (Bradshaw, 1986; Stokes, 1986; Dortch, 1972; 1997a; 1997b; David et al., 1990, 1991, 1994; Flood, 1970; Fullagar, 1995; Gregory, 1994; O’Connor, 1995). Thick notched flakes and adze flakes which marked the earlier technological phase is supplemented after the mid Holocene by a distinctive technology of making projectile points. There are 3 phases in the rock art styles that are recognised widely in the Kimberley to the north and west: a rock engraving tradition, which is suspected to be of at least Pleistocene age, as well as 2 main painting divisions: earlier Bradshaw figures and later Wandjina figures (Welch, 1993; Walsh, 1994). In this study Wandjina paintings have not been observed in the immediate area. Engravings and paintings have been recorded throughout the study area (McNickle, 1991) includes the Keep River region within the broader style of the Victoria River District where changing paintings styles have been documented (David et al., 1994) which have been related to changes in the signifying systems and land tenure the Late Holocene.

The Rock Shelter

According to a dreaming story the Jinmium site is connected to locations that have important economic and ceremonial resources such as swamp foods, ochre, stone and yams. Jinmium was a female ancestor-being who was once pursued by Djibigun, a male ancestor-being. A senior Gajerrong man and traditional custodian, and a senior Murinpatha woman and traditional custodian, have defined the area of the site, in terms of proximity to the main outcrop and sandstone stacks 20-40 m high. In the story Jinmium turned to stone at this location where Djibigun catches her and turns into a small bird, associated with 2 ochre sources that are nearby. Aboriginal camp sites, both prehistoric and historic, on the sandy ground are indicated by glass, stone and other artefacts that cover an area of more than 5 hectares.

The rockshelter C1 is formed by a large loose boulder with a sloping side embedded in the sand sheet within the Jinmium area, about 50 m from the main outcrop and sandstone stacks. It has many cup-shaped pits or cupules, some of which extend below ground level, several paintings, and a floor area of 24 m². Beginning in 1992, archaeological investigations to complement research into contemporary and historical resource management and relations to land were carried out (Head & Fullagar, 1991; O’Neil et al., 1993; Head, 1994a; 1994b). The specific objectives of the excavation can be summarised as the investigation of:

· The nature of Aboriginal camp sites associated with the pastoral industry (Head & Fullagar in press);

· The prehistory of Aboriginal landscapes (Fullagar & Head in press;

· And the role of stone artefacts in the gathering and processing of plant foods (Fullagar, 1993; Atchison, 1994).

Conclusions

To summarise, Fullagar et al. have presented evidence that humans had occupied northern Australia earlier than 116,000 ± 12,000 BP, with artistic activity that is inferred from ochre that dates from between 75,000 and 116,000 BP, and ground mudstone that dates from slightly later, and rock engravings dating to earlier than 58,000 BP. Fullagar et al. admit this scenario is highly controversial but needs to be further tested at this site as well as others. Fullagar et al. say the main reasons to support the TL ages in this paper are:

· The consistency of the stratigraphy of the TL ages;

· Young TL dates obtained from the top of the sequence, which suggests that the maximum error on the lower samples, if incomplete TL resetting was a problem, would be 2,000 years;

· In the younger parts of the deposit there is good correspondence between TL and radiocarbon ages;

· Archaeological integrity of the deposit, including trends in the density of different components.

Fullagar et al. say the only reasons to doubt the TL ages are the possibility of saprolite being contained in sample W1646 and foreshortened temperature plateaux on some, though not all samples. Fullagar et al. argued that the high temperature data from which the ages were calculated has not been affected by this foreshortening. They say that the ages cannot be easily dismissed, though also they cannot be accepted unequivocally.

In³the uppermost sediments seeds were noticeably weathered and below 40 cm the number declined, which indicated that this record was influenced more by factors of preservation than cultural processes (Atchison et al., in prep.).

The Jinmium (C1) rockshelter excavations are at the base of an exposed sandstone boulder, and the sand sheet is located 10 m from the rock shelter (C1/IV). OSL and radiocarbon dating of the young sediments is supported by the seed and stone artefact chronology (Atchison et al., in prep.), in spite of a disturbance or contamination (Roberts et al/. 1998b). The published chronology of the sand sheet excavation (Fullagar et al., 1996) at Jinmium, unlike the rock shelter sediments, has never been revised. A TL age of about 76 ka BP at a depth of 6m was obtained for the sand sheet sediments between Jinmium and Goorurarmum (Ward, 2003; Ward et al., 2005). Which lends support to the chronology determined by TL dating of (Fullagar et al., 1996), which produced an age of 103 ± 14 ky BP at a depth of 5 m near the Jinmium site. It was noted by Fullagar et al., (1996) that stone artefacts are present throughout the sand sheet deposit, though the initial presence of stone points, ochre and seed artefacts was dated to about 2.9 – 3.9 ky BP.

The extreme weathering that is characteristic of monsoonal climates in semi-arid areas will decrease the potential for preservation of artefacts and bias a record in a sedimentary sequence in favour of younger material. An example comes from excavations in the Jinmium Rock Shelter where in the uppermost sediments seeds were noticeably weathered and below 40 cm the number declined, which indicated that this record was influenced more by factors of preservation than cultural processes (Atchison et al., in prep.). The lack of radiocarbon ages at depths greater than 150 cm in the Keep River region most likely is a reflection of in situ organic preservation resulting changes in the level of the water table.

see Keep River Region, Northwestern Australia, Comparison of Histories Inside and Outside Rockshelters

See Keep River Region, Eastern Kimberley, Australia – Comparative Occupation Records

* See Possible Global Ice Volume Changes and Geomagnetic Excursions and Earth Orbital Eccentricity

The Colonisation of Greater Australia in the Pleistocene - a Re-examination

Sources & Further reading

Josephine Flood, Archaeology of the Dreamtime, J. B. Publishing
Phillip J. Habgood & Natilie R. Franklin, The revolution that didn't arrive: A review of Pleistocene Sahul, Journal of Human Evolution, 55, 2008
Ward, I. (2004). "Comparative Records of Occupation in the Keep River Region of the Eastern Kimberley, Northwestern Australia." Australian Archaeology(59): 1-9.
Fullagar, R. L. K., D. M. Price and L. M. Head (1996). "Early human occupation of northern Australia: archaeology and thermoluminescence dating of Jinmium rock-shelter, Northern Territory." Antiquity 70(270): 751-773.