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  • Details concerning the reserves of iron ore in Australia have been tabulated in this report. The report provides estimates of the grade and probable reserves of ore for the known Australian deposits.

  • An examination of the New Cobar-Chesney-New Occidental area in 1947 concluded that the discordant contact between slaty and sandy beds in the area was a feature of major importance in ore localisation. Accordingly, an investigation was conducted in the vicinity of Cobar to determine whether a relationship existed between discordant contact and ore formation in that area, and to commence a detailed geological map on a regional scale of the Cobar-Nymagee mineral belt. The general geology, character of the discordant contact, stratigraphy, and economic geology of the area are discussed in this report.

  • The Tallandoon Antimony mine, known locally as Dalgliesh and Murphy's, is 2 miles northwesterly from Tallandoon store on the main Omeo Highway and just within the northeast boundary of the Parish of Tallandoon, County of Bogong. This record comprises a description of the general geology and geological report on the antimony deposits.

  • A diverse range of mineralisation, including porphyry and epithermal deposits, intrusion-related gold and other metal deposits, iron oxide-copper-gold (IOCG) deposits and orogenic gold deposits all have linkages to crustal growth and magmatic arcs. Furthermore, all of these deposit types are associated with fluids containing H2O, CO2 and NaCl in varying and differing proportions. In all cases, it can be argued that magmas are a key source of hydrothermal fluids for these types of mineral system, and that subduction processes are critical to controlling fluid chemistries, the metal-bearing capabilities of the fluids and depositional processes. The differences on typical/bulk fluid chemistries between deposit types can be explained in part by differences in the P-T conditions of fluid segregation from its magmatic source. The most significant control here is the pressure at which fluid forms from the magma as this has a strong effect on fluid CO2/H2O values. This is clearly exemplified by the rare occurrence of readily detectable CO2 in deep porphyry systems (Rusk et al., 2004). On the other hand, fluid Cl contents (which strongly influence its base metal carrying capacity) are very sensitive to the magma's bulk composition. However, only some subduction-related magmas are fertile, and the differences do not seem to be due solely to variations in effectiveness of depositional processes. So what controls the volatile content of the magmas? Isotopic and other evidence, in particular for S and Cl, shows (unsurprisingly) that the greater contents of these elements in arc magmas compared to other melts is due to contributions from subducted materials, although there may be additional, lower crustal sources of Cl. Variations in the budget of volatiles subducted may thus play a role in controlling the chemistry of magmas and associated hydrothermal fluids, but variations within individual arcs suggests that again this is not the entire story.

  • A review of mineral exploration activity in Australia for 2009. This extended edition includes coverage reported in the shorter edition.

  • This geophysical survey was undertaken as part of a campaign by the N.S.W. Mines Department and the Commonwealth Bureau of Mineral Resources to explore the ore possibilities of the Cobar Mining Field. Tests, made in January 1947, on specimens of ore from the operating mines showed that some of the ore from the New Cobar and Chesney Mines exhibited appreciable magnetisation due to its pyrrhotite and possibly magnetite content. The survey was commenced in March, 1947 using the magnetic method only as a first method of attack. Watts Vertical Force Variometers Nos. 15887 and 16128 were used, the field work being carried out by the writers. The geology of the area, object of the survey, results, and recommendations for future drilling are discussed in this report. Two accompanying plans are included.

  • The Wymah mine was visited with Dr. Fisher on Wednesday 25th July. Dr. Fisher has recently visited the mine with Dr. Owen and will be presenting notes embodying his observations, hence this report will be very brief and will refer only to features having a bearing on ore reserves.

  • Mapping carried out at Kuridala by C.J. Sullivan and R.S. Matheson during the period June 17th-27th has shown that the ore deposits occur in a major fault (and associated lesser shears). The existence of the fault system is considered to have been proved, and it has been traced, with some interruptions over a distance of three miles. It may extend for many miles beyond the present limits of mapping. The geological information given appears to rule out a number of chances of occurrence at shallow depth, formerly considered likely, and thus is somewhat discouraging. However, the work does indicate that repetition deposits are likely to be present and opens up intriguing possibilities.

  • The enquiry into this mine resulted from an application by the company for a loan from the Commonwealth to carry out exploration and development. The Tindalls Gold Mine has not been examined by the Bureau and unless this is done no definite statement about the ore possibilities of the property can be made. However, from past reports it seems likely that the deposit has a chance of producing a large tonnage of ore. Under present conditions and with the mining methods now employed, it is extremely doubtful whether ore of this grade could be mined at a profit. The ore reserves, mining, milling, costs, and general financial outlook with respect to the mine are discussed in this report.

  • This report describes a geophysical survey made in May 1952 and August 1953 at the Silver Valley mine workings, near Inverell, N.S.W. From the workings there is evidence of mineralisation along a well-defined fissure and one ore shoot has already been partly developed. The survey was made in an attempt to locate other ore shoots of sufficient size to warrant mining operations. Self-potential, magnetic and electromagnetic methods were used in the survey. The self-potential method showed a well-defined anomaly on the eastern extension of the fissure, indicating that a small body of sulphides may exist there with its centre about 300 feet east of the known ore shoot. The magnetic and electromagnetic results showed no pronounced anomalies which could be correlated with any defined ore shoot. Recommendations are made as to how the self-potential anomaly could best be tested. These comprise sinking a shaft at the centre of the anomaly, extending an existing adit, or driving a new adit from a point nearer the anomaly.