In response to applications by the Tasmanian Department of Mines and the interested company, Eagle Metal and Industrial Products Pty. Ltd., Tasmania, a geophysical investigation, including self-potential, electromagnetic and magnetic surveys, has been made over the copper-nickel deposits of the North Dundas Field, situated about 5 miles north-east of Zeehan, Tasmania. The nickel ore occurs in the foot-wall of north-striking ultrabasic dykes. The ore shoots already worked had proved very rich but quite small. Important results were obtained in the Cuni North Area only. Conductive indications which appear to be due to mineralization extend over a length of 800 to 1000 feet. The line of mineralization is intersected by cross faults. Drilling targets for five short diamond drillholes are given. Further exploration should be confined mainly to this area. The geophysical results indicate that mineralization farther south is limited in extent and perhaps of no economic interest.

Legacy product - no abstract available

The Bureau of Mineral Resources has commenced a geophysical investigation of the copper-nickel deposits in the Five-Mile district near Zeehan at the request of the Tasmanian Department of Mines, Hobart. The Department, in its Summary Report (1952) has indicated the possibility that further ore-bodies of economic value exist in the area. Therefore, the Bureau was asked to carry out a geophysical investigation of the whole area. The Department of Mines laid out the lines including cutting and pegging the traverses. The geophysical survey was begun in May, 1952, with a programme including self-potential, magnetic and electro-magnetic measurements. This interim report has been prepared to present the geophysical results obtained to date and to discuss their significance. Self-potential and magnetic results are discussed.

A geophysical survey, comprising self-potential and electromagnetic methods, was made during the 1952 and 1953 field seasons at the Labour Victory Copper Mine, about 7 miles north-north-west of the Mt. Elliott Copper Mine, near Selwyn, Northern Queensland. The self-potential survey covered an area of 2,400 feet x 900 feet, but owing to other operational commitments during the 1953 season, the electromagnetic survey was confined to the southern part of the area. The primary object of the work was to determine the extent of the mineralisation associated with the known lode, which strikes north-south through the centre of the surveyed area. The self-potential survey revealed a well-defined anomaly nearly 1,000 feet long, in the northern part of the area. The axis of this anomaly is parallel to, but about 75 feet west of, the known lode. The disused main shaft of the now idle mine is at the southern end of the anomaly, which in this vicinity deviates slightly towards the south-east, i.e. towards the known lode. No workings exist in the area of the indication, and no outcrops were found, the rock formations being hidden for the most part by alluvium. The electromagnetic results confirmed those of the self-potential survey, but the electromagnetic indication extends farther to the south. The results suggest that the indication may be caused by lenticular bodies and that these are disturbed by cross faults. No mineralised deposits were indicated by the electrical results in the southern part of the area. It is recommended that some trenching and geological and geochemical work be done in the area of the strong electrical indication. If the results of the testing show that the indication is not due to graphitic or pyritic schists, it is recommended that a number of diamond drill holes be put down. Suggested locations for five such drill holes are given. If the anomaly is due to ore the geophysical results suggest an ore body of considerable size.

This report presents the results of detailed geological mapping of an area of approximately seven square miles surrounding the Mount Elliott copper mine, Selwyn, Queensland. The survey was made to determine the relationship between the geological structure and the mineralized zone containing the Mount Elliott copper deposit. A geological map of the actual exposures has been compiled (Plate 1) and interpretations of this data are shown on one plan (Plate 2) and eight sections (Plates 3, 4, 5 and 6). This report is intended as a supplement to the report by C.J. Sullivan (1951) and should be read in conjunction with it.

This report is supplementary to a report on the Kuridala Copper Field, Cloncurry district, Queensland, by C.J. Sullivan and R.S. Matheson (1950) and should be read in conjunction with that report. Sullivan and Matheson showed that, in the known deposits, ore occurs in the Hampden Fault, where slates in the hanging-wall of the fault are thrust against the resistant amphibolites occurring in the footwall (western side) of the fault. The rocks to the west of the fault were known, from mapping carried out by Broadhurst (1936), to be folded into a synclinal structure and it was postulated by Sullivan and Matheson that further ore may be found where the fault intersected amphibolites occurring stratigraphically below the amphibolites near which the known ore occurs (Sullivan, and Matheson 1950, Plate 1, Regional Cross Section). It was realised by Sullivan and Matheson that the prediction of a position of the amphibolites, at depth, involved considerable uncertainty and it was thought that further mapping of the Western Syncline might enable a reasonably accurate interpretation of the position of the amphibolites to be made. The [present] field work was carried out between 20th August and 18th September, 1951, by K.W.B. Iten and R.A. Searl of the Bureau of Mineral Resources and J.H. Brooks of the Geological Survey of Queensland. The general postulations by previous investigators concerning the relationship of geological structure to ore occurrence were checked but no detailed investigation was made of the size, shape and grade of known ore-bodies; the present investigators consider that the interpretation by Sullivan and Matheson (1950) of the structural controls of ore deposition may be correct.

During the past three to five years small amounts of oxidized copper ore have been reported from various localities in the James Ranges to the west of Alice Springs. During a visit to Alice Springs in July of this year information on these deposits was obtained from the Resident Geologists, A.D.M. Bell, and it is considered that potentially they may be of considerable importance and Bell has been instructed to investigate them further. The deposits are briefly discussed in the monthly report by Bell dated 3rd July, 1953. In this report he states that the rocks to the west of Alice Springs, where limestones are developed only on a comparatively small scale, are not likely to contain ore deposits to the extent of those to the east of Alice Springs where extensive limestone deposits occur. This concept is discussed below. [A supplementary note is enclosed which describes an inspection of the area which was conducted in September 1953].

Porphyry copper deposits are the world's primary source of copper and can also host a variety of secondary commodities identified as critical by the U.S. Geological Survey (U.S. Geological Survey, 2022). These deposits occur primarily along convergent plate margins, and their metal association and geochemical characteristics are reflective of whether the deposit formed in continental/island arc, back-arc, or syn- to post-collisional environments (e.g., Hofstra and others, 2021). Based on this association, understanding the location, age, and endowment of global porphyry deposits can be leveraged to identify prospective regions for discovery of new porphyry deposits along these ancient margins. This data release is a compilation and update from previously published global and regional datasets of porphyry copper deposits and prospects. The data sheet includes deposit names and their location, age (if known, and including analytical method), deposit classification based on Hofstra and others (2021), interpreted tectonic origin, and grade-tonnage compiled from public databases where available. The final spreadsheet represents the most up-to-date published information of global porphyry copper deposits and prospects as of Spring 2024. References Hofstra, A., Lisitsin, V., Corriveau, L., Paradis, S., Peter, J., Lauzière, K., Lawley, C., Gadd, M., Pilote, J., Honsberger, I., Bastrakov, E., Champion, D., Czarnota, K., Doublier, M., Huston, D., Raymond, O., VanDerWielen, S., Emsbo, P., Granitto, M., and Kreiner, D., 2021, Deposit classification scheme for the Critical Minerals Mapping Initiative Global Geochemical Database: U.S. Geological Survey Open-File Report 2021–1049, 60 p., https://doi.org/ 10.3133/ ofr20211049. U.S. Geological Survey, 2022, 2022 Final List of Critical Minerals: Federal Register Document 2022-04027, p. 10381-10382. (available at https://www.federalregister.gov/documents/2022/02/24/2022-04027/2022-final-list-of-critical-minerals).

URL: https://geoscience.data.qld.gov.au/dataset/cr055570 GSQ REPORT 85, COPPER MINING IN THE CLONCURRY AND MT ISA FIELDS, 1971

Sediment hosted gold deposits in Nevada were first mined in the 1960s from open pit mines with large tonnage and low grade resources. Since that time, continuing exploration and discovery have identified extraordinary resources, and together these deposits now form the second-largest gold endowment on Earth, surpassed only by the Witwatersrand Gold Fields of South Africa. The data herein are part of a larger U.S. Geological Survey (USGS) project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. The point and polygon layers within this database represent locations of mines, mineral occurrences (which includes deposits and prospects), and mining districts in an approximately 200-square mile area northwest of Carlin, Nevada. Tables contain additional information such as commodity, geology, deposit types, activity status, deposit resources, and mine production. The extent of surface workings, when visible on imagery, is also captured and shows the relative size of mining operations. All data were compiled from publicly available sources published from 1910 - 2017. Where possible, data were compiled from primary source reports rather than from syntheses of past reports. Although the selected area does not include the entire Carlin Trend, the area, which covers nine 7.5-minute quadrangles, does contain a wide range of deposit types described through a variety of public data and information. These data are being compiled by the USGS Mineral Deposit Database project with support from the Bureau of Land Management.