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  • Geophysical surveys were made in three adjoining areas -the Razorback, Grand Prize and Intermediate areas - in the Dundas Mineral Field near Zeehan, Tasmania. The aim of the surveys was to assist in the search for tin, which in this region occurs in association with sulphides. Electromagnetic, self-potential (S -P.) and magnetic methods were used.

  • An attempt was made to measure directly the line integral of the geomagnetic field around a closed circuit with an area of 3620km2. The intensity and direction of the horizontal component of the magnetic field were measured at 146 sites spread around the circuit, which was located near Carnarvon (Western Australia), where local irregularities due to crustal magnetism are small. The result is not significantly different from zero, but the uncertainty is larger than the average magnitude of curl B over the Earth, according to the recent world magnetic charts

  • The geology of the Ranken 1:250,000 sheet area, Northern Territory. (BMR Explan. Notes and map.)

  • Thirty-four core samples from the Commonwealth subsidized Frome-Broken Hill Co. Pty Ltd Flaxman's Hill No.1 well, Otway Basin, Victoria, provided spores identifying the Cretaceous age of the Otway Group penetrated in the well. Microplankton, spores and pollens which might form the basis of future correlation of the Upper Cretaceous of the basin, following comparison with their distribution in Port Campbell No.1 well and Belfast No.4 bore, are noted. Cretaceous outcrop samples from the Otway Group were also examined. Problems arising from tentative correlations between the Lower Cretaceous Merino Group and the Otway Group and the relation of subsurface and outcrop Wangerrip Group are outlined, but no solutions to them are offered at this stage.

  • This Record describes seismic refraction surveys at three dam sites on Barambah Creek, near Murgon in Queensland, made at the request of the Irrigation and Water Supply Commission of Queensland. The seismic velocities are tentatively interpreted in geological terms, and the results are, plotted in the form of cross-sections showing depth and velocity of the various layers. Special attention should be given to rocks with seismic velocities about 8000 ft/sec, which are interpreted as moderately weathered bedrock. Depending on the type of dam to be designed, these may be suitable as foundation rocks. The seismic work suggests that fault or shear zones are present at all three dam sites.

  • The Bureau of Mineral Resources mapped the Ranken and Avon Downs 1:250,000 Sheet areas in 1961. These areas, which make up the north-eastern part of the Georgina Basin, also form the eastern part of the Barkly Tableland The geology of the two sheet areas is described by Randal and Brown (1962a and b). During the survey, information on 125 bores was obtained and collated to evaluate the underground water resources of the region for its present and future development. Ninety-six (96) bores are currently operating in the region, and they are tapping sub-artesian water from Lower Palaeozoic aquifers between 245 and 635 feet above sea-level.

  • Explanatory notes on the Pellew 1:250,000 geological Sheet - SD 53-16. (BMR Explan. Notes and map.)

  • During the months from June to October of 1961, a field party from the Bureau of Mineral Resources, Geology and Geophysics mapped the Mount Liebig (F/52-16) and Mount Rennie (F/52-15) Sheet areas, which will be referred to as the Mount Liebig area and the Mount Ronnie area in the text. The aim of this survey was to tie the work done in the MacDonnell Range by Prichard and Quinlan (1962), to the work done by ~Fells, Forman and Ranford (1961) on the Macdonald (F/52-14) and Rawlinson (G/52-2) Sheet areas.

  • A seismic velocity survey was carried out in Associated Freney Oilfields Nerrima No. 1 Bore by the Bureau of Mineral Resources on the 10th August 1955. The well is situated on the Nerrima Dome in the Fitzroy Basin, W.A. Some trouble was experienced with cable breaks for the shallow part of the hole, but in general it was possible to recognise the true formation break. Average measured velocities ranged from 8000 ft/sec near the top to 12,200 ft/sec for the total depth of the bore.

  • A seismic velocity survey of the APM Development Pty Limited No. 1 bore at Rosedale, Victoria, was made by the Geophysical Branch of the Bureau on the 3rd May 1960 using a TIC three-component well geophone. Measurements were taken with the geophone suspended in the well at selected intervals down to 5500 ft. The object of the survey was to measure the average vertical seismic velocities to depths down to the bottom of the bore, and to examine interval velocities over selected depth intervals.