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  • Between April and July 1962, a seismic party from the Bureau of Mineral Resources, Geology and Geophysics made a seismic reflection and refraction survey in the Moree area of New South Wales. The main purpose of the survey was to investigate whether the southern extension of the Bowen Basin beneath the Great Artesian Basin from Meandarra to Toobeah continued as far south as Moree and joined the Sydney Basin. Three east-west traverses were shot using a method of reconnaissance reflection shooting, the first near Dolgelly Bore, the second through Moree, and the third through Bellata. The third traverse was extended eastward as far as the Horton River to investigate the Hunter-Bowen Thrust zone. In addition, three north-south refraction traverses were shot in the middle, and on both ends, of the east-west traverse through Moree. A north-south reflection traverse was shot north of Dolgelly Bore.Results in the Moree and Bellata areas were of poor quality and in the Bellata area in particular, owing to surface basalt flows, little information was obtained. The Hunter-Bowen Thrust area was not distinguished by the seismic work. The seismic results indicated that the trough of sediments extending southwards through Dolgelly Bore was at least 7500 ft deep south of Dolgelly Bore. The eastern margin of the trough is probably an overthrust fault. In the Moree area, two troughs were indicated, viz. the Biniguy Trough in the east where about 7000 ft of sediments was estimated separated by the Pallamallawa Ridge from the Moree Trough in the west where about 11,000 ft of sediments was estimated. Poor results in the Bellata area failed to indicate whether the Moree Trough joined the Sydney Basin.

  • Between 3 May 2012 to 24 June 2012 Geoscience Australia undertook two major surveys off the coast of the Northern Territory in the Petrel Sub-Basin. The data acquisition was funded through the National Low Emissions Coal Initiative (NLECI) and the Petrel Sub-basin was selected in particular as it has been identified as a prospective area for CO2 storage. One of these surveys, GA336 acquired 4091 kilometres of 2D seismic reflection data. Following on from the completion of the seismic processing of this data was further investigative work investigative work such as this analysis. Four prime lines, GA336-107, 110, 205 and 207 along with the well logs, Flat-Top1, Petrel 1A and Petrel 4 were selected for further 2D Simultaneous Inversion and Rock Physics Modelling. Previous Pre Stack Depth Migration had been undertaken on these lines and the PSDM Angle Stacks were imported along with the relevant horizon interpretation into the Jason integration algorithms.

  • The Georgina-Arunta deep seismic reflection line (09GA-GA1) has provided an image of the entire crust in this part of central Australia. At a first approximation, beneath the Neoproterozoic-Devonian sedimentary basins, the crust can be divided into four distinct regions, namely, the Aileron, Irindina and Davenport Provinces, and the Ooratippra Seismic Province. Each of these regions is separated from each other by major, crustal-scale faults. The observed crustal architecture has implications for geodynamic models for the evolution of the region, implying amalgamation of these crustal blocks in the Paleoproterozoic and major shortening and basin inversion in the Paleozoic.

  • Towa.:ccis the end of 1960 , the Bureau. of Mineral Resources, Geology and Geophysics made a brief seismic survey in the Winton area of Queensland to resolve an apparent contradiction between the interpretations of gravity and aeromagnetic results previously obtained in the area. Gravity and aeromagnetic results both suggested the occurrence of a large fault or fault zone about 20 miles north-west of Winton, but the gravity and aeromagnetic interpretations differed regarding the direction of throw of the fault. A nine-mile seismic reflection traverse was surveyed across the supposed fault. The seismic results indicate the presence of a large fault or monoclinal fold with dowthrown side nouth-wast as suggested by the gravity values and also a smaller fault or monocline about two miles south-east with downthrown side south-east. The variations in thckness of Mesozoic rocks caused by these features were insufficient to explain the observed Bouguer gravity anomaly values, but the seismic results left open the possibilitues that there may be a considerable thickness of pre-Mesozoic sedimemts north-west of the main monocline or fault. It is postulated that the steep gravity gradient observed may be due to a large fault whose main movement took place in pre-Mesozoic times. Indications are that there is 5000 to 6000 ft of Mesozoic sediments in tha area.

  • The Bureau of Mineral Resources Seismic Party No. 2 conducted a survey from 15th May to 25th August 1961 in the Amadeus Basin. Reflection and refraction traverses were shot at intervals, along or near the Alice Springs/Port Augusta railway line, from Polhill in the north to Finke in the south. In broad terms the object of the survey was to obtain across the Amadeus Basin a north-south seismic cross-section that would aid in investigating the stratigraphic cross-section and structural relations especially on the southern margin of the Basin. Access and drilling problems caused the progress of the survey to be slow. The statistics of the operation are included in three appendices. During the course of the seismic survey, the Bureau also made gravity surveys covering the area; gravity-meter readings were made along all seismic traverses.

  • Ice thickness measurements carried out by field parties based on Mawson during 1957-59 consisted of: (:) regional traverses in the form of closed loops extending several hundred kilometres inland from Mawson; (ii) semi-detailed traverses in the vicinity of a line of ice flow stakes about 25 Km from Mawson. The regional traverses showed that, beyond about 175 Km inland, the area surveyed is influenced strongly by the Lambert Glacier - Amery Ice Shelf system situated some 200 Km to the East. Preliminary contour plans of the ice and rock surfaces show fairly close correspondence. A sub-glacial extension of a range of mountains outcropping through the ice 80 Km to the East of the traverses was found. Work along the semi-detailed traverses close to Mawson detected sub-glacial extensions of the outcropping mountain ranges in the area. These extensions may explain the general direction of the coastline near Maws on.

  • 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. It was apparent that signals reached the geophone by transmission along the cable by which it was suspended, and these interfered with the signals reaching the geophone along a path directly through the ground. This made interpretation difficult; however, by careful inspection of both the vertical and horizontal components of the signals received by the geophone at each depth, an interpretation has been made that yields a series of velocity/depth determinations. The average vertical velocity increases from 5000 ft/sec at the surface to 8930 ft/sec at a depth of 5500 ft. The average velocity in the Tertiary (0-2159 ft below datum) was computed to be 6420 ft/sec; the -werage velocity in the Mesozoic rocks penetrated (2159-5314 ft below datum) was 12,180 ft/sec. Two reflection spreads laid out and recorded in the vicinity of the bore showed the presence of reflectors at depths estimated to be in excess of 7700ft.

  • Aeromagnetic and gravity surveys were made in the Tambo-Augathella area by Magellan Petroleum Corporation in 1959 and 1960 respectively. A probable fault shown in the magnetic interpretation is almost coincident with a zone of steep gravity gradients which was interpreted as indicative of a fault or of steeply dipping strata. However, the normal gravity interpretation would indicate a deeper cross-section to the south-east of this zone, whereas the magnetic interpretation suggests that the fault is downthrown to the northwest. The present survey was undertaken by the Bureau of Mineral Resources to find out which interpretation was the more probable. A reflection seismic traverse was shot at right angles to the closed gravity 'high' and across the zone of steep gravity gradients. Results show that the closed gravity 'high' is the expression of an anticline and that the zone of stoep gravity gradients is caused by steep dip to the south-east on the flank of the anticline. The gravity interpretation is therefore found to be more representative of actual conditions.

  • A ~400 km long deep crustal reflection seismic survey was acquired in central Victoria, Australia, in 2006. It has provided information on crustal architecture across the western Lachlan Orogen and has greatly added to the understanding of the tectonic evolution. The east-dipping Moyston Fault is confirmed as the suture between the Delamerian and western Lachlan Orogens, and is shown to extend down to the Moho. The Avoca Fault, the boundary between the Stawell and Bendigo Zones, is a west-dipping listric reverse fault that intersects the Moyston Fault at a depth of about 22 km, forming a V-shaped geometry. Both the Stawell and Bendigo Zones can be divided broadly into a lower crustal region of interlayered and imbricated metavolcanic and metasedimentary rocks and an upper crustal region of tightly folded metasedimentary rocks. The Stawell Zone was probably part of a Cambrian accretionary system along the eastern Gondwanaland margin, and mafic rocks may have been partly consumed by Cambrian subduction. Much of the Early Cambrian oceanic crust beneath the Bendigo Zone was not subducted, and is preserved as a crustal-scale imbricate thrust stack. The seismic data have shown that a thin-skinned structural model appears to be valid for much of the Melbourne Zone, whereas the Stawell and Bendigo Zones have a thick-skinned structural style. Internal faults in the Stawell and Bendigo Zones are mostly west-dipping listric faults, which extend from the surface to near the base of the crust. The Heathcote Fault Zone, the boundary between the Bendigo and Melbourne Zones, extends to at least 20 km, and possibly to the Moho. A striking feature in the seismic data is the markedly different seismic character of the mid to lower crust of the Melbourne Zone. The deep seismic reflection data for the Melbourne Zone have revealed a multilayered crustal structure that supports the Selwyn Block model. Raw data for this survey are available on request from clientservices@ga.gov.au

  • A seismic survey using the Australian National Seismic Imaging Resource (ANSIR) Hemi 60 Vibroseis vehicles, ARAM24 acquisition equipment and Pelton controllers was carried out in the Curnamona Province of South Australia. A total of 197.6 km of 2-D seismic reflection data were collected to 18 seconds two way time over a single line at a nominal 60 fold CDP coverage. These data were acquired under contract by Trace Energy Services (2003) and by Terrex Seismic (2004). The survey commenced in August 2003 but was abandoned due to wet weather. Survey operations were recommenced and completed in July 2004. The project was undertaken to meet the objectives of ANSIR proposal 03-02R as lodged by researchers from PIRSA, Office of Minerals, Energy and Petroleum, SA. The principal scientific objective of this survey was to provide a regional crustal seismic image of the Curnamona Province. This dataset will assist in the understanding of the geological architecture and resource potential of the region particularly in areas under cover. This line links with a seismic transect in the Broken Hill Block undertaken by Australian Geological Survey Organisation (AGSO, now Geoscience Australia) in 1996 and provides a future opportunity for an eventual east-west continuation across the Adelaide Geosyncline and the Gawler Craton. The survey was funded by PIRSA, Office of Minerals, Energy and Petroleum, SA and the pmd*CRC with project supervision undertaken by ANSIR and in-kind support from Geoscience Australia (GA). Raw data for this survey are available on request from clientservices@ga.gov.au