A wide-angle reflection seismic survey coincident with a regional transect through Northeastern Yilgarn Craton focused on the Leonora-Laverton Tectonic Zone, Western Australia, was carried out to supplement deep seismic reflection studies. The major objectives were: to collect high-density refraction information for offsets of up to 60 km; to carry out a comparative study of near-vertical and wide-angle seismic images of the crust in the study area; to obtain velocity information for the upper crust. The survey deployed 120 short period recorders with a 500 m spacing. Acquisition parameters used for the wide-angle reflection experiment were selected so that it would to fit into the schedule and technology of the conventional reflection survey. The same vibrations were recorded in both surveys simultaneously. The major challenge in processing the wide-angle data was to manage the huge volume of information. The processing sequence included sorting into receiver and source gathers, cross-correlation with reference sweeps and stacking original seismic traces to form single source point traces, producing seismograms from individual traces and finally creating seismic record sections from separate seismograms. High amplitude seismic signal from vibroseis sources was recorded at least up to 50 km offsets in the first arrivals, and later arrivals were observed down to 12 s next to sources. A preliminary upper crustal model developed from the wide-angle data shows that the thickness of a high velocity layer, corresponding to the greenstone rocks, is 4.0-4.5 km. The boundary separating this layer from a low velocity layer below it is possibly a compositional boundary between greenstones and underlying felsic gneisses. There is no evidence for high velocity material below this boundary. Assuming the Moho belongs to deepest reflections modelled, total crustal thickness in the region can be speculatively estimated in the range 32-37 km.

The main aim of the Canning Basin project is to improve our understanding of the stratigraphic and structural evolution of the basin as a basis for more effective and efficient resource exploration. The first stage of the project involved studies on two contrasting scales; a basin-wide compilation of structural information (not reported here), and a detailed study of the stratigraphic architecture and evolution of the outer portion of the central part of the Lennard Shelf, some of which is presented here. The basic information generated in the Lennard Shelf study has been compiled into three folios: 1) a Well Folio containing sequence interpretations of the more important wells in the area; 2) a Seismic Folio containing sequence interpretations of seismic lines; and 3) a Map Folio containing structure contour and isopach maps. These explanatory notes accompany the Seismic and Map Folios. More detailed discussions of the interpretations of the Devonian-Carboniferous sequences are presented in Jackson Sr others, (1992); Kennard SE others, (1992) and Southgate St others, (1993).

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Seismic Test Survey conducted by the Bureau of Mineral Resources, Geology andGeophysics (BMR) (now Australian Geological Survey Organisation (AGSO)) during the early part of 1989. The objective of the survey was to test the suitability of the seismicreflection technique for proposed regional deep reflection seismic lines in the Gunnedah Basin and Cobar Basin. The major emphasis of the test survey was to assess the feasibility of acquiring shallow and deep seismic reflections in order to examine various geologicalmodels of bounding faults and basin structure. The survey acquired data from five sites in the Gunnedah Basin and three sites inthe Cobar Basin. The quality of data in the deeper part of the sections, i.e. 6-15 seconds (TWT), varied from very good to excellent. Seismic reflections in the sedimentary part ofthe succession were, in general, very poor, but some surprisingly good seismic reflectionevents were obtained below the Pilliga Sandstone in the Gunnedah Basin. The test survey indicated that the deep seismic reflection technique in theGunnedah Basin and Cobar Basin would provide data that would be of assistance in developing new geological models, and an understanding of fault geometries and basinstructure, and would assist the exploration for mineral and petroleum resources in the future.

Resources, Geology & Geophysics (now Australian Geological Survey Organisation (AGSO))conducted a seismic reflection, seismic crustal refraction and gravity survey in southeastern Queensland from August to November 1986. The primary objective of the survey was to complete seismic reflection coverage in the Dalby-Toowoomba area between Traverse 14 and Traverse 16 recorded during the BMR S.E. Queensland seismic survey in 1984. Secondary objectives, subject to survey progressincluded recording additional seismic reflection data east of Traverse 16 (1984) over the Beenleigh Block south of Brisbane, and a 100 km of seismic reflection data south of Mitchellover a deep crustal seismic reflection feature delinated on Traverse 14 (1984) centred at SP4030. Overall the survey objectives would allow the completion of a continuous deepcrustal seismic reflection profile of 1110 km length across southern Queensland, the basis of a lithospheric transect study in the southern region of Queensland. The survey obtained a total of 181 km of 6-16 fold CMP seismic reflection data in theBeenleigh, Darling Downs and Mitchell areas, using the Sercel SN368 seismic acquisition system. Both the primary and secondary objectives were achieved, although equipmentfailures were a major problem in causing decreased production rates. Gravity observations were made at 360m intervals along all traverses. The record presents operational information on the seismic reflection survey and preliminary sections of seismic traverses.

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From 10 to 17 April 1997, the Australian Geological Survey Organisation (AGSO) chartered the 85 m Research Vessel Melville from Scripps Institution of Oceanography on a cooperative scientific basis, to map the sea bed east and northeast of Tasmania including the deep water part of the Gippsland Basin. The vessel was equipped with the SeaBeam 2000 multibeam sonar system, capable of swath-mapping the morphology and roughness of the sea bed in a swath 3.5 times as wide as the water depth. The central beam gave a 12 kHz bathymetric profile. Other equipment employed included a magnetometer and gravity meter. Navigation, by military standard GPS using the P code, had an accuracy of about 5 m. Detailed ship's tracks for the survey, from south to north, are shown in Figures 2-5. The aims of the cruise were to determine the morphology and sea bed character of selected areas, to aid in tectonic, basin and sedimentological studies, to aid the fishing industry, and to provide critical information for future seismic profiling and geological sampling. Satellite gravity images, and sparse bathymetric and seismic profiles, were used to plan the survey.

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In 2006, deep seismic reflection profiling was carried out along six transects across the Mount Isa Inlier. The seismic lines were jointly funded by the Geological Survey of Queensland, Geoscience Australia, the Predictive Mineral Discovery Cooperative Research Centre and Zinifex Pty Ltd. (now Oz Minerals). In 2007, a further three seismic lines were collected by Geoscience Australia and the Geological Survey of Queensland from Cloncurry to south of Charters Towers via Croydon and Georgetown. This paper presents some highlights from the geological interpretations of the seismic lines.

A ~400 km long deep crustal reflection seismic survey across central Victoria, Australia, was carried out in 2006 as a collaborative project between the pmd*CRC, Geoscience Australia, the Victorian Government, Ballarat Goldfields NL, Gold Fields Australasia Pty Ltd and Perseverance Corporation Ltd, using the facilities of the National Research Facility for Earth Sounding (ANSIR). The aim was to cross several Neoproterozoic-Palaeozoic basement zones and provide information on the crustal architecture, particularly across the highly prospective Palaeozoic rocks occurring along strike to the north of the major Victorian goldfields, such as Bendigo. In the west, the Moyston Fault is a major east-dipping planar fault near the eastern edge of the Grampians-Stavely Zone, which was probably the eastern margin of continental Australia in the Cambrian. It cuts through the entire crust to the Moho. The Stawell Zone, immediately east of the Moyston Fault, has the geometry of a doubly vergent wedge. The boundary between the Stawell Zone and the Bendigo Zone farther to the east is the Avoca Fault, which appears to be a west-dipping listric fault that links to the Moyston Fault at a depth of about 22 km, forming a Y-shaped geometry. Internal faults in the Stawell and Bendigo zones are almost entirely west-dipping listric faults, which cut deep into the highly reflective lower crust, interpreted to be stacked ? Cambrian oceanic crust. Previous models advocating the presence of a mid-crustal detachment are not supported by these deep crustal scale faults. The boundary between the Bendigo and Melbourne zones, the Heathcote Fault Zone, forms a zone of strong west-dipping reflections about three kilometres wide to a depth of at least 20 km, and possibly to the Moho. The fault zone is complex and contains a boninite-tholeiite association along with blueschists in a serpentinite-matrix melange, and oceanic sedimentary rocks. The Melbourne Zone contains a deformed sedimentary pile up to 15 km thick, and contains previously unrecognised north-dipping listric faults, interpreted to be thrusts. The Governor Fault separates the Melbourne Zone from the Tabberabbera Zone and contains similar rocks to the Heathcote Fault Zone. Near the surface, the Governor Fault dips to the north at about 10°. The seismic character of the lower crust below the Melbourne Zone (the "Selwyn Block") is significantly different to that observed below the Bendigo and Stawell zones, and consists of several very strong subhorizontal reflections about 5-6 km thick starting at about 18 km depth, with a less reflective zone below it. In summary, the deep seismic data across central Victoria has allowed the geometry of the rocks and structures mapped at the surface to be projected through the entire crust, thus providing important constraints to test previous tectonic models.