The archaeology of native wells: Aboriginal Wells on Sweers Island in the Gulf of Carpentaria of northern Australia

The Aboriginal Wells on Sweers Island in the Gulf of Carpentaria of northern Australia are generally regarded as native wells, features excavated and used by Aborigines. Adjacent to each well lies a low, flat mound, composed of the spoil removed from the depressions. A core through one of these mounds and into the underlying sediments revealed an increase in phosphorus content between 0.40 and 0.28 m. This is a marker of the dramatic changes in environmental chemistry resulting from European pastoralism, which began on the island some time between 1861 and 1880. This unit must have formed after the middle of the nineteenth century. It represents the soils and sediments developed on the early contact land surface. The overlying unit, found between 0.28 and 0.08 m, consists of material excavated from the adjacent pit. It is composed of a mixture of the early contact soils and sediments and the basal deposits. The upper 0.08 m of the sequence represents the modern soil, developed on the spoil from the depressions. This must post-date the excavation of the wells.
Since the basin floor had been enriched with phosphorus prior to the excavation of the depressions, the wells as they exist today must post-date European contact. Although it is conceivable that pre-existing native wells may have been exploited and enlarged by the pastoralists, there is no stratigraphic, archaeological or historical evidence to support this thesis. Furthermore, even if the wells had existed prior to European contact, given the scale of the excavation, there can be no element of the pre-contact features still remaining. Alternatively, the wells may have been dug (or European features re-excavated) by Aborigines in the twentieth century after the abandonment of the island by Europeans. There is no suggestion of permanent Aboriginal occupation during that time, however, and all the evidence points to transient Aboriginal use of the Island during this period.
It seems unlikely that early European settlers would have erroneously attributed a feature of European origin to Aboriginal agency. If the name can be traced back to the nineteenth century, therefore, it would strongly suggest that the wells were initially of Aboriginal origin. The name Aboriginal Wells, however, seems to have been employed only since the 1970s when visitors from the mainland ascribed an Aboriginal genesis to these features.