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  • This report covers the work done by the author who was geophysicist with the Australian National Antarctic Research Expedition at Macquarie Island from April to December, 1953. It is a sequel to Records 1953/30 and 1954/32 and deals with observatory routine and maintenance and other general duties required of the geophysicist. The report contains the results of absolute magnetic observations and initial earthquake phases. Detailed tables of scientific results will be published separately in reports at present in preparation.

  • Report on the activities of the administrative and technical sections in the Katherine-Darwin area, to July, 1954. A brief account is given of geological and geophysical operations. The results of prospecting and development work are summarised.

  • The following report concerns the geology and mineralization of two uranium prospects in the Gimbat - Snake Creek Area of the Northern Territory. One of these prospects, referred to as Sleisbeck, can be recognised as one of the most favourable yet discovered in the Northern Territory. The radioactivity occurs in a quartzite breccia outcropping over a length of 1.5 miles and with a width of as much as several hundred feet. Geiger counter readings of 2 - 100 times background, occur frequently along the entire length of the outcrop, visible mineralization being present at three separate localities. The state of this mineralization, its associations and the geological settings are favourable to the possible occurrence of uranium mineralization at depth. Recommendations are made for further work, and problems in regional geology are discussed. The writer considers the sections of this report designated "Mineralization" and "Conclusions" to be the most important for a knowledge of the actual uranium occurrences. The remaining information is mainly geological, and, while highly pertinent, may not be of urgent interest to readers with a limited amount of time.

  • Report on the activities of the administrative and technical sections in the Katherine-Darwin area, to August, 1954. A brief account is given of geological and geophysical operations. The results of prospecting and development work are summarised.

  • This report deals with the application of geophysical methods (other than radiometric) to the Coronation Hill Radioactive Deposit. Results of radiometric gridding of the surface and costeans, field sludge assays, and radiometric drill hole logging are not treated as these are included in entirety in R.B. Allen's report "The Coronation Hill Uranium Prospect," Bureau of Mineral Resources Record 1954/17. Structural indications from magnetic evidence are discussed. These comprise several faults, or zones of weakness, one of which may coincide with the axis of the surface radio-activity. Several interesting magnetic features for which no cause can be proposed are also noted. The highly uncertain nature of the deductions made is emphasised. The method of approach to geophysical applications at Coronation Hill is detailed, and recommendations are made for possible future work.

  • This quarter, with its favourable climatic conditions, has seen the greatest activity in the field for the year. Thirteen geologists and five geophysicists, together with many assistants, have operated in the area on many prospects. The Darwin office and laboratory are well-established and providing many services to the public such as assaying, instrument repair, and geological and geophysical advice. Detailed geological and geophysical work has been commenced or continued at the following prospects: A.B.C., Edith River, Burrundie, Brock's Creek and Adelaide River, while minor investigations have been carried out at many other localities. Three drills have operated throughout the quarter. Regional geological mapping has been continued over a wide area. The amount of work being done will decrease during the coming quarter due to the approach of the "wet" season.

  • Self-potential and magnetic surveys made in the vicinity of the Mount Cleveland Tin Mine, near Waratah, Tasmania, are described and discussed. The first survey, which is described in Part I of this report, was made in April and May, 1953, at the request of the Department of Mines, Tasmania. The object of the survey was to ascertain whether geophysical methods could detect the known area of mineralisation and, if so, whether any additional areas of mineralisation could be discovered. Results of the first survey show that the geophysical anomalies, particularly the self-potential ones, coincide with the old mine workings. The anomalies over Luck's and Hall's workings, however, cover larger areas than the actual mine workings, thus indicating that further sulphide mineralisation may exist beyond these old workings. Anomalies not related to the old workings appear in an area north-west of Deep Creek, between traverses O and R. Both self-potential and magnetic methods revealed anomalies along these traverses between 350.E and 650.E, where geological investigation has also shown mineralisation to exist. Based on the results of the first survey, the grid was extended and surveyed to the north-east and south-west in March and April, 1954. This second survey, which is described in Part 2 of the report, shows that the anomaly connected with Henry's workings does not extend to the north-east, but terminates sharply between traverses P and Q. Some additional anomalies were recorded in the north-eastern extension of the grid, but in the south-western extension there was no geophysical evidence of mineralisation. It is suggested that further mining exploration work should be concentrated mainly near the former mine workings and in the area to the north-west of Deep Creek, between traverses O and R. Some prospecting trenches should also be put down to test the minor anomalies in the north-eastern part of the area.

  • In the course of geological investigation of the area included in the Katherine, Mt. Todd and Lewin Springs 1-miles sheets, carried out by J.H. Rattigan and A.B. Clark, Bureau of Mineral Resources, A.B. Clark found, in September 1953, uranium mineralization subsequently known as the A.B.C. Prospect, 11 miles north-north-east of the township of Katherine. This report is a record of the detailed investigation which followed the discovery.

  • Report on the activities of the administrative and technical sections in the Katherine-Darwin area, to May, 1954. A brief account is given of geophysical operations. The results of prospecting and development work are summarised.

  • 1952-3 was the third successive year of geophysical work at Macquarie Island. During the previous year Mr. W.H. Oldham was mainly concerned with the preparation of the establishment for future operation as an observatory. This record outlines how, as a consequence, 1952-53 was devoted to full-time technical proceedings in both geomagnetism and seismology. It does not present the results of the scientific observations in full. These will be presented in a further report, but it does give in tabulated form absolute magnetic values observed and seismic phases recorded.