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  • Systematic testing of South Stradbroke Island was started on 5th January, 1948. The boring and concentrating of samples were carried out by Associated Minerals Pty. Ltd., Southport. Sitting, levelling and mapping of boreholes was carried out by the Bureau of Mineral Resources. Between January and June, boring was directed towards the high active dunes adjacent to the east coast, and the areas of fixed, vegetated dunes west of the active dunes. The results of the testing work are recorded in this report. The occurrence of heavy minerals has been tabulated. Eight accompanying locality, section, and contour plans are included.

  • One gram of sample No. 1 and 2 grams of No. 2 were dissolved in about 100mL of hot water. After dissolving the soluble portions the solutions were filtered and the undissolved portions dissolved and weighed. This weight subtracted from the original weight of the sample gave the amount of soluble salts. The filtrate was diluted to 250 mls with distilled water, 100 mls being used for Ca and Mg determination. The results of this experiment are given in the report.

  • At the request of the Broken Hill Proprietary a geophysical test survey, employing gravity and magnetic methods, was carried out near Wollongong, N.S.W. by geophysicists of the Bureau. The area over which these tests were made is part of the Southern Coalfield of N.S.W. and plans are being made to develop a colliery in it. The subsurface geology is known in part from five drill holes, namely, Nebo No. 2, 5, and 6 and Wongawilli No. 7 and 8. Basalt sills of considerable thickness were encountered in Nebo No. 6 and Wongawilli No. 8. The proximity of sills to the coal seams has resulted, in parts of the Southern Coalfield, in the cindering of the coal, and for this reason it is a matter of considerable importance in planning a colliery to know the area occupied by the sills. The technical aspects of testing, results, and conclusions are discussed in this report.

  • In November, 1947, at the joint request of the Queensland Government and four companies which are associated with the search for oil in the area, the Bureau commenced geophysical work in the Roma district of Central Queensland. During the first phase of the geophysical operations, gravity and magnetic methods were applied in the reconnaissance of a large area. The object of these operations was to disclose gravity or magnetic anomalies which might be related to geological structures, indicate the broader structural elements of the sedimentary basin in which the oil and gas occur, and enable areas to be selected for investigation by more exact methods. The purpose of this report is to state clearly the geological problem and the geophysical methods adopted in the attempt to solve it. The geology of the area, possible oil-bearing structures, and the application of geophysical methods to date, are discussed. A sketch map and geological section plan are included.

  • Monitoring changes in the spatial distribution and health of biotic habitats requires spatially extensive surveys repeated through time. Although a number of habitat distribution mapping methods have been successful in clear, shallow-water coastal environments (e.g. aerial photography and Landsat imagery) and deeper (e.g. multibeam and sidescan sonar) marine environments, these methods fail in highly turbid and shallow environments such as many estuarine ecosystems. To map, model and predict key biotic habitats (seagrasses, green and red macroalgae, polychaete mounds [Ficopamatus enigmaticus] and mussel clumps [Mytilus edulis]) across a range of open and closed estuarine systems on the south-west coast of Western Australia, we integrated post-processed underwater video data with interpolated physical and spatial variables using Random Forest models. Predictive models and associated standard deviation maps were developed from fine-scale habitat cover data. Models performed well for spatial predictions of benthic habitats, with 79-90% of variation explained by depth, latitude, longitude and water quality parameters. The results of this study refine existing baseline maps of estuarine habitats and highlight the importance of biophysical processes driving plant and invertebrate species distribution within estuarine ecosystems. This study also shows that machine-learning techniques, now commonly used in terrestrial systems, also have important applications in coastal marine ecosystems. When applied to video data, these techniques provide a valuable approach to mapping and managing ecosystems that are too turbid for optical methods or too shallow for acoustic methods.

  • A geological field party was engaged in this area from 9th May to 30th September, 1948. This report provides an account of the field operations undertaken throughout this period and describes personnel involvement.

  • The beach sands on which investigations were carried out, were mainly from beaches along the eastern coast of Australia and from islands adjacent to this coast. A high percentage of the mineral grains of the heavy mineral fraction in these sands have grain sizes within the range -100 to +200, referred to British Standard Sieves. The grain size of the minerals, combined with the fact that the grains are quite well rounded, makes the heavy mineral sands an ideal subject for separation using the inclined method with the Isodynamic Separator. The use of this method, and the results obtained, are described in this report.

  • The deposits of heavy-mineral sands which are at present being exploited along the East Coast occur on or within a few hundred feet of the ocean beaches. The occurrence of this deposit at a distance of nearly 1.5 miles from the beach suggests the possibility that other deposits may be found at some distance from the coast line. Of incidental interest is the possibility that the deposit, which presumably was formed by wave or surf action, may be at slightly higher level than the deposits adjacent to present day beaches. The locality, examination process, origin, and nature of the deposits are discussed in this report. The results, including estimates of the quantities of heavy mineral concentrates and the grades of the mineral bearing sands, are tabulated here.

  • Database containing analytical data and interpretations from the Geoscience Geoscience (GA) geochronology program. Includes some legacy methods and externally sourced data. A collection of analytical data to support geochronology data or ages used in other reporting and publications.

  • This report is a summary of information collected between November, 1948 and July, 1949 in the course of visits to the United Kingdom and the United States. The main subjects investigated were the complete gasification of coal, particularly in respect of its application to Victorian brown coal, the production of oil by synthesis and the production and refining of shale oil. Information was sought on a considerable number of other interests in the field of fuel technology as the opportunity offered. The authorities consulted were invariably experts in their respective fields, and great care was taken to record their information accurately. The report is a summary of recent developments and not an exhaustive study of the subjects mentioned. A considerable mass of detail has been excluded but is available on record for further reference.