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  • The Oaklands-Coorabin Coalfield in the Riverina Division of New South Wales has been known for many years. Seismic refraction tests were carried out on a number of sections to assist in the interpretation of the gravity results during July and Sepetember, 1949.

  • Despite long history of studies the Wallaby Plateau offshore Western Australia remains a controversial feature. Analysis of interval seismic velocities from Geoscience Australia's 2008/09 seismic survey 310 in conjunction with seismic reflection interpretation provides new insights into the geology of the Plateau. Seismically distinctive divergent dipping reflector sequences (DDRS) have been identified. The seismic character of the DDRS is similar to seaward dipping reflector sequences (SDRS) of inferred volcanic composition. Initial analysis of seismic velocity profiles indicated affinities between the DDRS packages and known sedimentary strata in the Houtman Sub-basin. Effect of water loading on seismic velocities is commonly ignored in offshore studies. However, direct comparative analysis of interval velocity patterns between areas of significantly different water depth requires various water pressure related changes in velocity to be accounted for. There are controversies in methodology and application of water depth adjustment to seismic velocities, and presentation of velocity models as function of pressure rather than two-way time, or depth emerges as a possible solution. Water depth adjustment of seismic velocities analysed in our study reduces distinction between SDRS, DDRS and sedimentary strata such that discrimination between volcanic and sedimentary strata in DDRS or SDRS is equivocal. A major uncertainty of this interpretation is due to a lack of the reference velocity model of SDRS and DDRS investigated globally.

  • On 12th July 1960, a velocity survey of the A.A.O. Pickanjinnie No. 1 bore was made by the Bureau of Mineral Resources. The bore had been drilled to a depth of 5218 ft and was surveyed to the bottom. The average velocities for the Mesozoic rocks and the Timbury Hills Formation are similar to those measured in the Timbury Hill No. 2 bore. However, it seems impossible to correlate individual units within the Mesozoic sequence according to their velocity.

  • Following a month of preliminary experimental seismic work in the latter part.of 1964 the Bureau of Mineral Resources carried out a reconnaissance seismic survey of the southern part of the Georgina Basin, mainly in the Northern Territory, from April to October 1965. In most areas reflections proved very difficult to obtain. A number of different techniques were tried, including various shot andgeophone pattern arrangements, noise testing,collinear offset shooting, airshooting and multiple coverage, but no technique was found which was generally successful in providing useful reflections. The seismic results tended to confirm gravity indications that there is a shelf area between BMR 12 Bore and Tobermory and provided no indications that there are deep Palaeozoic troughs similar to the Toko -Syncline in the survey area.

  • Geoscience Australia acquired the Papunya Seismic Reflection Survey in 2010. The survey involved the acquisition of high resolution seismic reflection data along a single 11.5km traverse (10GA-PA1). The purpose of the survey was to obtain information on key palaeovalley characteristics for potential groundwater studies. This dataset contains seismic data and images only, a full report on the results of the palaeovalley study can be found in GA Record 2012/09. Raw data for this survey are available on request from clientservices@ga.gov.au

  • The preliminary investigation was made when the Bureaut s seismic party was held up by flooded rivers, while on its way t o Christmas Creek in May, 1954. Results show that the seismic aethod is applicable to the Broome area, and that a sedimentary section of the order of 12,500 feet exists. They further show that a syncline and anticline not known from the surface geology may possibly exist at depth.

  • Seismic reflection traverses were surveyed across the Perth Basin at Cookernup, W.A. These traverses were planned to find the thickness and dip of the Basin sediments adjacent to the Darling Scarp and to discover any faulting or folding within them; also to determine the applicability of the seismic method as a tool for both regional and detailed investigation in this area. Seismic refraction traverses were surveyed to help in the solution of problems encountered in the interpretation of the reflection cross-sections. The survey indicated a considerable thickness of sediments about 20,000 ft, at the eastern margin of the Basin near the Darling Scarp, and suggested tectonic structure that is not indicated in surface geology, The reflection traverses indicated that sediments (presumably Lower Palaeozoic or Precambrian) lying deep in the Perth Basin may continue underneath the Darling Scarp and abut the granitic gneisses etc. of the Western Australian Shield on an overthrust fault plane. The overthrust fault, if it exists, does not reach the surface, but is covered to a depth of possibly some few hundred feet by younger sediments and also by alluvium eroded from the Darling Scarp. Some reflection and refraction shooting was done in an attempt to test this and other hypotheses, but the results crc inconclusive. Gravity results strongly suggest a normal fault, and if normal faulting is the case, the reflections from beneath the outcropping basement are possibly derived from shear zones, Some probable 'reflected refractions' were also observed. There is scope for further seismic testing but it is considered that conclusive evidence could only be provided by drilling.

  • This OGC WFS web service (generated by Geoserver) serves data from the Geoscience Australia Rock Properties database. The database stores the results of measurements of physical properties of rock and regolith specimens, including such properties as mass density, magnetic susceptibility, magnetic remanence and electrical conductivity. The database also records analytical process information such as method and instrument details where possible.

  • The EGGS database contains point depths to chronostratigraphic surfaces obtained from boreholes and four magnetic modelling methods. In regards to the depths obtained from inclined boreholes there are uncertainties on their measurement of the true vertical depths. These are currently being looked into and would be resolved in due course. Future development will include AEM, reflection seismic, MT and passive seismic. A Web Service will allow the public to download this data and will be accessed through the EFTF (Exploring for the Future) web portal.