New Rb-Sr isotopic data are presented for the Jervois Range area in the eastern part of the Arunta Block. The post-metamorphic Jinka and Jervois Granites yield an age of about 1750 m.y. An alaskitic granite is dated at about 1460 m.y. Pegmatite formation occurred about 1660 m.y. ago. Mineral ages are generally younger than total-rock ages, but no values significantly less than that of the alaskitic granite were found. This means that the Alice Springs Orogeny, which extensively reset large areas of the Arunta Block to the west, did not affect the Jervois area. In this and other geochronological comparisons, the Jervois area seems more akin to the rocks of the Tennant Creek Block, 400 km to the northwest, than to those of the Arunta Block.

An oily liquid and several types of bitumen were found in the silicified porous carbonate-rich Looking Glass Formation, in a BMR stratigraphic hole drilled in the Proterozoic McArthur Basin in 1979. The bitumen is accompanied by sulphides (including pyrite, chalcopyrite, and marcasite), and has been trapped beneath a thin claystone which is present at the unconformity at the base of the Balbirini Dolomite. It is thought to be a residue from oil generated lower in the McArthur Group or in the Tawallah Group and then trapped in the Beetle Spring Anticline. Proterozoic strata as old as the McArthur Group (ca. 1600 m.y.) should not be overlooked in the search for hydrocarbons in Australia.

276 km of continuous seismic reflection profiles have been obtained from the inter-reef areas of the Capricorn Reefs. Five reflectors were identified, three being widespread: reflector A, the shallowest, is found only close to modern reefs; reflector C is widespread and varies from flat-lying to irregular; the deepest reflector, D, is limited to the area north and west of Heron Island, where it is flat-lying. All the reflectors are assumed to represent erosional surfaces, and the ages of the intervening sequences are not known. Either reflector C, or the present sea bottom and reflector A, represent the surface of the Holocene transgression.

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Granulite facies country rocks of the Giles Complex in the western Musgrave Block are predominantly of felsic igneous (intrusive or extrusive) origin and were metamorphosed at about 1200 Ma. The protoliths of some Y -depleted orthogneisses may represent primary felsic crust derived by partial melting of a hornblende±garnet-bearing, but feldspar-poor, mafic source, whereas others (including syn-metamorphic orthopyroxene granites) have geochemical features (notably depletion in Sr, but not Y) more consistent with intracrustal melting. 1188±4 Ma and ~1060 Ma hornblende-biotite granitoids (including rapakivi varieties) south of the Hinckley Range mostly have compositions (high HFSE, LREE, and Th/U, and low Sr) consistent with relatively high-temperature partial melting of near-anhydrous granulite facies crustal rocks, at least partly caused by emplacement of mafic magmas (including the Giles Complex). Granitic basement rocks to the Bentley Supergroup in the western Musgrave Block differ from granitoids of the Hinckley Range area in including a significant proportion of Y-depleted, Sr-undepleted rocks which may represent new felsic crust. The 1078±5 Ma felsic Smoke Hill Volcanics of the Bentley Supergroup have compositions (high HFSE, LREE, and Ga/A1, and low mg) typical of A-type and intraplate granitoids. Like the Hinckley Range hornblende-biotite granitoids, they may have been derived by partial melting of granulite facies lower crustal rocks during emplacement of mantle-derived magma ( e.g., the associated Mummawarrawarra Basalt), or, alternatively, by fractionation of basaltic magma. However, the relatively high Nb of the felsic volcanics implies a source compositionally different from either the exposed felsic crustal rocks or mafic volcanics. The somewhat younger Nd TDM model ages (1460-1570 Ma) of the Smoke Hill Volcanics compared to granulite facies metamorphics west of the Hinckley Range (1610-1900 Ma) are consistent with derivation of the former either from a relatively young crustal underplate or directly from mantle-derived magma.

The Mirackina Palaeochannel (MPC) consists of a chain of parallel silcrete-capped mesas extending for about 200 km through the far north of South Australia. The channel fill comprises fluvial conglomerate and sandstone; has a siliceous and ferruginous duricrust caprock; and overlies kaolinised and weakly silicified Bulldog Shale. The MPC presents a striking example of inverted topography and exhumed palaeodrainage on airphotos and Landsat imagery. However, a study of a section of the MPC 60 km long west and northwest of Arckaringa homestead, about 150 km north of Coober Pedy, has shown that most of its non-indurated fill has been removed by erosion. Fill remnants are preserved beneath parallel lines of silcrete cappings created by groundwatcr discharge along the channel margins. These caprocks have been extensively tilted and displaced by landslides within the underlying Bulldog Shale. The ferruginous silcrete capping of the MPC is typically about 30 m lower than the adjacent Stuart Range and Arckaringa Hills land surfaces, which are probably equivalent to the Cordillo Surface of early Tertiary age. The palaeochannel sediments are thought to be Miocene, though their silicification may have been completed later (possibly during the Pliocene) and over a short interva l.

The Brunhes/Matuyama (B/M) polarity transition (0.78 Ma) marks the end of the last major period of reversed polarity of the Earth s magnetic field. Weathered regolith materials with reversed polarity chemical remanent magnetisation (CRM) must, therefore, predate the B/M transition. Reversed polarity magnetisation can be preserved in a wide variety of regolith materials in eastern Australia, particularly in oxidising environments. At Sellicks Beach and Hallett Cove near Adelaide, the B/M transition is identified in a strongly mottled unit, the Ochre Cove Formation. In Canberra, strongly weathered fan gravels on the east side of Black Mountain have a mixture of reversed and normal polarities, indicating initial weathering and deposition before 0.78 Ma and continued weathering since then. In north Queensland, a soil formed on a 2.46 Ma basalt flow has reversed polarity in the lower B horizon, indicating that, over the last 0.78 Ma, pedogenesis has had little or no effect on the secondary iron minerals carrying the magnetic remanence in that part of the profile.

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Aboriginal and Torres Strait Islander people have lived successfully on the Australian continent for at least 40 000 years. Their quest for water, based on an intimate knowledge of their environment, particularly in arid Australia, was a skilled and specialised endeavour. Following the European occupation over 200 years ago, the Aboriginal and Torres Strait Islander population decreased rapidly due to the ravages of colonisation. Introduced infectious diseases, such as smallpox, typhoid fever, leprosy, and venereal disease, were a major factor in increased mortality and morbidity; tribal land displacement and massacre of some communities was another major factor. The current health status of Aboriginal and Torres Strait Islander people is poorer than that of other Australians. Their pattern of mortality and morbidity shows the burden of both infectious and lifestyle diseases. This poor health status is associated with wide-ranging socioeconomic disadvantage. The environmental living conditions of many Aboriginal and Torres Strait Islander people remains an impediment to major health improvement. The lack of adequate and safe water supplies is an important factor in the continued poor health status of many communities. A recent national survey of housing and infrastructure needs of Aboriginal and Torres Strait Islander population centres has improved our understanding of the current water supply situation. Providing a safe adequate water supply alone will not automatically result in any significant improvement in health. Many other factors are involved. However, safe water is the doorway to health and health is the prerequisite for progress, social equity and human dignity (Napalkov, 1992). This paper examines the relationships between water and health and why the many national surveys and enquires have failed to secure a noticeable and sustainable benefit among Aboriginal and Torres Strait Islander people.