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  • This Record describes a seismic refraction and resistivity survey at a proposed dam site on the Pieman River, Tasmania. The purpose of the survey was to determine the thickness and nature of overburden and the nature of bedrock. Seismic results indicate that the overburden is up to 110 ft thick; it consists of soil, scree material, and decomposed and weathered dolerite. The bedrock consists of jointed and unweathered dolerite.

  • This Record describes a seismic refraction survey at Callide Creek 49.8-mile dam site, near Biloela, Queensland. The survey was made at the request of the Queensland Irrigation and Water Supply Commission. Depths to unweathered bedrock and other rocks were determined by their seismic velocities and are shown on cross-sections. From general geological information and the results of drilling in the area, the seismic velocities can be translated into geological terms. Comparison with drilling results suggests that seismic depth estimates are about 18 per cent too low. After correcting this systematic error, the depth determinations are accurate to within 10 ft. Young's modulus for the unweathered bedrock, determined by the seismic method, is estimated at about 7 to 9 x 10,000,000 lb/in2.

  • The basic rocks of the Katherine - Darwin region have been divided into eight geographical groups and the field relationships and petrology of the rocks from each group are discussed.

  • This record details the results of an experimental seismic survey done in the Oodnadatta area of the Great Artesian Basin in July and August 1957. The purposes of the survey were to find whether reflections could be recorded from beneath duricrust, a siliceous surface deposit, and whether structures mapped by surface geological methods persist with depth.

  • The writer visited Japan to attend the International Conference on Cosmic Rays and the Earth Storm at Kyoto in September 1961. Data from satellites, cosmic rays, geomagnetic and ionospheric recordings, whistlers, and airglow combine to give a broad picture of the solar-terrestrial relations involved in magnetic disturbances, but there are many features that still require explanation.

  • Lower Cretaceous marine microfossils have been recovered from a bore on the Plenty River, Hay River 4-mile sheet. Their presence demonstrates a westerly extension of the marine Lower Cretaceous below the sand cover of the Simpson Desert.

  • A new ophiuroid, Ophiomicros bathursti gen. et sp.nov. is described from Cenomanian (Upper Cretaceous) strata of Bathurst Island, Northern Territory. The new genus may be allied to Ophiura Lamarck, 1816 and Amphiura Forbes, 1842 but is readily distinguishable from both these genera by unusually large oral plates and small adoral plates.

  • An inspection of the area around Bathurst Island Mission was made to pick a bore site for domestic water for the Mission. The Mission is on a low, flat laterite plateau that has developed on Cretaceous mudstone. The mudstone is at least 1,000feet thick and is a poor aquifer, so that the underground water supply will be restricted to the laterite, which is slightly more than ten feet thick in most places. The existing wells should be deepened, and radial horizontal holes should be drilled in the hope of intersecting more water-bearing cavities in the laterite. Pollution is an important problem in this area. All abandoned wells should be filled in and the wells that are in use should have a concrete curb around the top and should be tightly covered.

  • This report is an outline of the symposium on 'Groundwater in the Arid Zones' conducted by the International Association of Scientific Hydrology (I.A.S.H.) at Athens, Greece from the 11th to the 21st October, 1961..

  • This Record describes a vibration investigation made by the Bureau of Mineral Resources, Geology and Geophysics at the request of the Alliance Assurance Company Ltd. It was believed that breakage of a number of windows in the curtain walls of the Company's building, Alliance Chambers, at 408 Collins Street, Melbourne, might be caused by vibrations. The purpose of this investigation was to measure the amplitude and frequency of vibrations on different floors, and to trace the source of the vibrations.