The Tanami region has become one of Australia?s premier Proterozoic gold provinces, having already produced 122 t of gold, and still has high exploration potential. This region contains more than 60 gold occurrences including three established gold fields (Dead Bullock Soak, The Granites and Tanami) as well as several significant gold prospects (Groundrush, Titania, Crusade, coyote and Kookaburra). The Callie deposit (>5 Moz total resource) located in the Dead Bullock Soak goldfield is currently the largest mine in this region. Fluid inclusion studies indicate that the ore fluids in the Dead Bullock Soak and The Granites goldfields were low to moderate salinity (4 ? 10 wt.% NaCl eq), moderate to high temperature (260 ? 460 ?C) and gas rich. In contrast, ore fluids in the Tanami goldfield were low temperature (120 ? 220 ?C) with only minor CO2. O and H isotopic data are consistent with either a metamorphic or magmatic origin for the ore fluids with some mixing with meteoric fluids evident in the Tanami district. The fluid inclusion data also indicate that the deposits have formed over a range of physico-chemical conditions and depths. Groundrush appears to have formed at the greates depths and has the most reduced (CH4-rich) fluids. The Granites goldfield and the Callie deposit formed at shallower depths. The Granites fluids were CO2-rich but also had variable N2 and CH4. The Callie fluids show only small variations in temperature and salinity and are more oxidised with only CO2 and N2 being detected. The Tanami deposits appear to have formed at the shallowest levels and are dominated by low-salinity aqueous fluids, although some CO2-bearing fluids have also been detected. Considerable uncertainty surrounds the age of gold mineralisation. The spatial relationship between many of the gold deposits and granitoids has led to proposed genetic links between granite intrusion and mineralisation. These granites have since been dated at between 1825 and 1795 Ma. Preliminary 40Ar/39Ar results from sericite from the Carbine pit in the Tanami goldfield yields a total gas age of 1810 Ma, i.e. similar to the age of the granites. However, 40Ar/39Ar analysis of biotite in mineralised veins from Dead Bullock Soak indicate an age of 1720 ? 1700 Ma. This suggests that mineralisation at Callie may be related to fluid migration driven by the Late Strangways Orogeny that was responsible for widespread deformation and metamorphism in the Arunta Province to the south-east. Results of this study indicate that gold deposits of the Tanami region are surprisingly diverse, with some being basalt and dolerite hosted, some in banded iron formations and some being sediment hosted. Moreover, fluid inclusion data shows that the deposits formed over a range of depths and 40Ar/39Ar dating may indicate the occurrence of more than one mineralising event. Consideration of this diversity from a mineral systems perspective, highlights the likelihood that undiscovered gold deposits in the Tanami region will have a range of characteristics and may occur in a number of different lithologies.

No abstract available

Globally, salt lakes are major sources of lithium, potash, borates and other strategic mineral commodities. Salt lakes, or salars, in the semi-arid to arid regions of Chile, Peru, Argentina and Bolivia contain most of the world's low cost supply of lithium, while salt lakes in Jordan, Israel and China are significant sources of potash. Despite the large number of salt lakes distributed across Australia, public domain knowledge of saline lakes and their associated groundwater systems as potential sources for lithium, potash and other commodities is limited. This report has reviewed the publicly available information on Australian salt lakes and is accompanied by four maps showing which lakes have the highest potential for lithium, boron, potash and calcrete-hosted uranium.

The Uranium Systems Project is a key part of the $59m Onshore Energy Security Program (OESP) underway at Geoscience Australia (2006-2011). The project has three objectives: (1) develop new understandings of processes and factors that control where and how uranium mineralisation formed, (2) map the distribution of known uranium enrichments and related rocks in Australia, and (3) assess the potential for undiscovered uranium deposits at regional to national scales. Objective (1) has been addressed initially by reviewing current classification schemes for uranium deposits. Most schemes emphasise differences in host rock type and list 15 or more deposit types. An alternative scheme is proposed that links the apparently separate deposit types in a continuum of possible deposit styles. Three end-member uranium mineral systems are: magmatic-, basin-, and metamorphic/metasomatic-related. Most recognised deposit styles can be considered as variants or hybrids of these three end-members. For example, sandstone hosted, unconformity-related and "Westmoreland" style deposits are viewed as members of basin-related uranium systems and which share a number of ore-forming processes. Identification of the spatial controls on uranium mineralisation is being investigated using numerical modelling, with the Frome Embayment of SA as a first case study. Mapping the distribution of uranium in objective (2) has commenced with the release of a new map of Australia showing the uranium contents of mainly outcropping igneous rocks, based on compilation of whole rock geochemical data. A clearer picture of uranium enrichments is also emerging through cataloguing of an additional >300 uranium occurrences in the MINLOC mineral occurrence database. Finally, the recently completed Australia-wide radiometric tie-line survey is providing a new continent-scale view of uranium, thorium and potassium distributions in surface materials. To assess potential for undiscovered uranium deposits, new OESP data in targeted regions of Australia are awaited, such as airborne EM, seismic and geochronology data.

The North Pilbara Terrane has the largest variety of mineral deposits of any Archaean province. It contains the oldest known examples of volcanic-hosted massive sulphide (VHMS), lode Au, porphyry Cu, orthomagmatic Ni-Cu-PGE-V, pegmatitic Ta-Sn and epithermal deposits, with a diversity more characteristic of Phanerozoic mobile belts. Despite this diversity the North Pilbara Terrane appears to lack any major mineral deposits, with the exception of the Wodgina Ta-Sn pegmatite field. Below, we present the metallogenic history of the North Pilbara Terrane in the context of its tectonic development and then compare it to other Archaean provinces to assess controls on metal endowment.

As part of the North Pilbara NGMA Project, AGSO (now Geoscience Australia), together with Newcastle University and the Geological Survey of Western Australia (GSWA), have been conducting a research program to document the geological setting, characteristics and genesis of Au deposits of the North Pilbara Terrane. This record summarises some results of this research program. This research has concentrated on turbidite-hosted lode Au deposits in the Indee and Nullagine areas as well as basalt and ultramafic-hosted deposits in the Mt York-Lynas Find area. In addition to these areas, AGSO's research also concentrated on epithermal deposits in the Indee area, and less detailed studies were undertaken on lode Au deposits at Gold Show Hill and Klondyke. This research program was designed to complement recent (e.g., Neumayr et al. [1993; 1998] on the York deposits and Zegers [1996] on the Bamboo Creek deposits) and ongoing (e.g., D. Baker, University of Newcastle] at Mt York-Lynas Find) programs conducted at the other institutions. This Pilbara Gold Record is supported by an extensive GIS dataset, providing many new digital data sets, including a number of variations of the magnetics, gravity, and gamma-ray spectrometry. A solid geology map, and derivative maps, mineral deposits, geological events, and Landsat 5-TM provide additional views. This data set complements the 1:1.5 Million scale colour atlas (Blewett et al., 2000).

No abstract available

Tanami Region, the largest gold province in the Northern Territory, has produced 122 t of gold, has a known remaining resource of 190 t, and has high exploration potential. Most deposits are concentrated in three goldfields - Dead Bullock Soak (DBS), The Granites and Tanami. Significant mineralisation is also located at Groundrush (0.7 Moz Au), Oberon (0.48 Moz Au) and Crusade (0.1 Moz Au) deposits, as well as the Coyote prospect in WA. Gold mineralisation is late in the tectonic cycle, has a spatial assocaition with late orogenic felsic intrusives, and is coincident with late D5 structures. DBS goldfield (remaining resource 23.6 Mt at 5.6 g/t Au) contains stratabound mineralisation in folded greenschist facies siltstone, BIF and chert of the Dead Bullock Formation. At Callie, which is the largest deposit in the Region, mineralisation is in D5 quartz veins associated with fold closures within metasiltstone. It is dominated by free gold (70%) with some auriferous arsenopyrite. The remaining DBS deposits consist of BIF and chert hosted mineralisation associated with arsenopyrite, pyrrhotite and minor pyrite. The Granites goldfield (remaining resource 1.9 Mt at 3.8 g/t Au) comprises stratabound mineralisation within intensly folded amphibolite facies BIF of Dead Bullock Formation. Gold occurs in sulphides (apy, po, py) disseminated in BIF, quartz and quartz-carbonate veins. The Granites goldfield lies in close proximity to Inningarra and The Granites granitic suites (1815?4 and 1795?5 Ma respectively), and is associated with D5 shearing. Tanami goldfield (remaining resource 6.01 Mt at 3.2 g/t Au) comprise auriferous quartz veins in sub-greenschist facies basalt and interbedded sedimentary units of the Mount Charles Formation. Mineralisation is controlled by three sets of D5 faults striking 350-010o, 020-040o, 060-080o and dipping east to southeast. There is a close spatial relationship with the Coomarie and Frankenia granites (1815?4 and 1805?6 Ma respectively). Gold occurs in sulphides (py, apy, po);and vein textures indicate high level mineralisation. Wallrock alteration involves bleaching of basalt and sediments to produce sericite+quartz?pyrite?carbonate assemblages. Groundrush (resource 3.2 Mt at 4.5 g/t Au) comprises auriferous arsenopyrite in quartz veins within dolerite, but structural relations are still not clear. Titania (resource at Oberon 4.1 Mt at 2.6 g/t Au) contains auriferous pyrite and arsenopyrite in D5 quartz veins within detrital and graphitic sediments of the Killi Killi Formation; Minotaur ( resource 1.0 Mt at 2.4 g/t Au) contains auriferous sulphides (apy, po, py) disseminated in lower amphibolite schist of Dead Bullock Formation. Microthermometric and Raman spectroscopic studies of primary fluid inclusions indicate that Callie fluids changed character with time, characterised by decreasing temperature, increasing salinity and changing gas contents. The fluid conditions were 280-400oC and 6-12 wt% NaCl in pre-ore quartz veins; 220-360oC, 8-22 wt% NaCl eq and abundant CO2 in ore-stage quartz veins; 180-320oC and 12-18 wt% NaCl eq in post-ore quartz veins, and 80-160oC and 14-28 wt% NaCl eq in late post-ore carbonate veins. At The Granites goldfield, the main population of ore stage fluid inclusions had a temperatures of 260-312oC and salinity 4-8 wt% NaCl eq. At the Tanami goldfield, the ore fluids had lower temperatures of 120-220oC and salinity below 12 wt% NaCl eq; fluids here were largely degased. At Groundrush, ore fluids had the highest temperatures of 390-430oC and salinity of 4-10 wt% NaCl eq. Groundrush fluids also contained CO2 and exceptionally high CH4. Based on fluid inclusion data, estimated depths of mineralisation were 8.3 to 5.5 km for Groundrush, 7.5 to 3.8 km for The Granites goldfield, 5.8 to 3.2 km for Callie and 1.5 to 0.4 km for the Tanami goldfield.

The discovery of the radioactive minerals carnotite and torbernite, in the vicinity of Rum jungle, was reported by Mr. Jack White on the 7th September 1949 in a letter to the Director of Mines, Alice Springs. Officers of the Department of Mines, Alice Springs confirmed his conclusions. The area was visited by J. Daly, J.F. Ivanac of the Bureau of Mineral Resources, and M. Sneddon of the Mines Department, Alice Springs late in September. They suggested that detailed geophysical and geological work should be carried out. H.J. Ward and G.F. Joklik made a detailed geological investigation in October and prepared a map which covers an area approximately half a mile by a quarter of a mile. A general reconnaissance of the country in the vicinity of Rum Jungle was also carried out. In conjunction with the geological work D.F. Dyson made a Geiger-Muller survey of the torbernite-carnotite deposit. An account of this investigation and its findings is set down in this report.

This report contains the results of a brief examination carried out from 1st to 7th October 1950 at Maranboy, Northern Territory, by the writer and Dr. J. Sleis, Geologist, who were assisted by the Inspector of Mines, Mr. W.A. McDonald. The purpose of this examination was to obtain the necessary data for a preliminary assessment of the tinfield based on the ore developed and won to date.