The Olympic Copper-Gold Province of the eastern Gawler Craton of South Australia, in hosting the Olympic Dam, Prominent Hill, Carrapateena and Moonta-Wallaroo deposits, has the greatest known iron-oxide, copper, gold and uranium (IOCGU) metal endowment of any geological province on Earth. The historic Moonta-Wallaroo copper-gold mining fi eld is within the Moonta sub-domain and is hosted by the ~1750 Ma Wallaroo Group that preserves some evidence of evaporitic sedimentation, similar to other major iron oxide-copper-gold (IOCG) provinces in Australia and North America. Observations in the Moonta-Wallaroo district indicate that mineralisation was broadly associated with intense metasomatic alteration, intrusion of granites and gabbros of the Hiltaba Suite, moderate grade metamorphism and intensely partitioned deformation. The driving force of this extensive ~1600 to 1500 Ma hydrothermal, magmatic and tectonic event was a major thermal pulse, the cause of which remains under debate. The vein-style mineralisation in the Moonta-Wallaroo district developed in ground prepared by ductile shearing. Widespread sub-economic copper mineralisation in the region is associated with intense regional magnetite-bearing skarn-like alteration of the Cloncurry type, with oxidation and hematite replacement of early magnetite. Targeting of structurally-controlled demagnetised zones and the oxidised margins of magnetic anomalies has been applied successfully in the northern Olympic Copper-Gold Province (e.g. Prominent Hill) and is also applicable to the Moonta-Wallaroo region. The recently discovered copper-gold mineralisation at the Hillside copper-gold deposit demonstrates the continued prospectivity of this southern portion of the Olympic Copper-Gold Province.

This is a public domain release of the Module 3 structural study from the Predictive Mineral Discovery Co-Operative Research Centre (pmd*CRC) and AMIRA (Australian Mineral Industry Research Association) Y1-P763 project which concluded in November 2005. An 18 month confidentiality period applied to this work but the resulting report is now able to be released. Research into the structural evolution of the Eastern Goldfields Superterrane (EGST) continued in allied projects (Y2 and Y4) as part of the pmd*CRC program. The Y2 project Final Report was released to the public as Geoscience Australia Record 2006/05. As of July 2007, the active Y4 pmd*CRC project has been continuing the work from the Y1-P763 and Y2 projects. Therefore, some interpretations of the structure of the EGST presented in Geoscience Australia Record 2007/15 have changed. One of the enduring assets of the original Y1-P763 Final Report is the very extensive data preserved in the appendices, which, due to their size, are available only on DVD. The philosophy behind the Y1-P763 report was to clearly separate data from interpretation, a move which has aided continuous improvement in the understanding of the structural evolution of the EGST. No structural difference between terranes. The only possible terrane accretion structures are the Ida and the Hootanui since the Ockerburry is extensional. No D1 N-S compression, early isoclinal shallowly dipping structures are interpreted to be extensional in origin. Long-lived ENE-directed extension marked during D1 which formed the major basin architecture for the greenstone sequences. There is a strong extensional event (D3) which postdates D2 compression and forms and deforms the late basins. The crustal architecture (observed in seismic) is controlled by D1 and D3 extension. It is not a thin-skinned fold and thrust belt. The NNW-trending tectonic grain in the Eastern Yilgarn was set up as a result of ENE-directed D1 and D3 extension with local extension vectors controlled by the exhumation of granite domes in the footwall to NNW striking extensional shear zones. The folding which the late basins unconformably overlay may have formed during extension. Further work is required to examine is this hypothesis holds true for every case not just around the Lawlers Anticline. The N-S tectonic grain in the Eastern Yilgarn is a function of D2 and D5 dextral transpression which has dissected the NNW-trending extensional architecture. D2 and D3 are spatially inversely related, i.e. where D2 is present D3 is absent and where D3 is present D2 is absent. This poses the question as to the significance or pervasiveness of the D2 contractional deformation. P-T dihedra work has resolved D2 and D5, B1B palaeostress to be predominantly ENE- to NE-striking. Contractional deformation is predominantly associated with strike-slip movement on N- to NNW-striking faults as opposed to thrusts. This study has recognised a N-S to NW-SE oriented low-strain contractional D4 deformation event. This deformation is typically expresses as either sinistral N- to NNW striking faults or E-W striking N- and S-directed thrusts. Few events have the structural style and intensity necessary for significant crustal thickening. This study recognised that gold is present in extensional structures although the majority of Au deposits lay in contractional structures. Gold deposits located in ductile shear zones are typically localised in the highest strain regions of the shear zone typically located at its centre. These high strain areas are typically marked by the presence of shear related foliation boudinage.

This dataset is part of a digital geological map of the Granites-Tanami Block which Australian Geological Survey Organisation has prepared by joining together as a seamless coverage 15 of the 1:250 000 geological maps which cover the province.The data layers in the digital map include geology, faults, lineaments structural data, mineral deposits and Australian Geological Survey Organisation drill hole locations. The digital data is available in Arcinfo/ Arcview or Mapinfo format. Topographic and cultural layers are not included: these can be purchased separately from AUSLIG.

Petroleum exploration within the Gippsland Basin has been focussed on major anticlines at the Early Tertiary "top Latrobe"unconformity, and to a much lesser extent on "intra-Latrobe" traps. Little information exists on the petroleum potential deep within the basin. Similarly, in the adjacent Bass Basin, most of the exploration effort has been concentrated at or near the top of the Latrobe Group equivalent, the Eastern View Coal Measures. Analysis of regional seimic data collected by BMR in 1982 suggests that the Bass and Gippsland Basins were initiated by NNE-SSW lithospheric extension, probably in the Early Cretaceous. A reactivation of these basin-forming extensional structures, particularly transfer faults, may have had a significant influence on petroleum migration and accumulation higher in the stratigraphic section. This operational report describes the first of two cruises to be undertaken by the R/V Rig Seismic in the Gippsland/Bass region(Nov - Dec.1988 & March - April 1989). These cruises aim to: (i) improve definition of the deep structure of the Gippsland and Bass Basins using basin-wide deep seismic (12+ seconds) transects, (ii) evaluate models for basin evolution (iii) develop concepts for petroleum migration andentrapment from the regional data and by analogy with the similar basins worldwide, and (iv) through the provision of regional seismic data assist the petroleum industry in carrying out seismic correlations. The cruises contribute to a number of studies by BMR of the structure, stratigraphy, evolution and resource potential of offshore basins along Australia's southeastern margin. This first cruise (Survey 82) was broken into four parts: (1) Equipment testing for future work: involving the measurement of drift on a HIfix radio navigation system, and testing IFP electronics for the deep recording objectives of the program, (ii) Recording of approximately 470 km of relatively deep-water reflection profiles in the eastern Gippsland Basin (12s records, 52.4 litre air-gunarray for Line 82/001 , 26.7 litre for lines82/002 & 3). (iii) Recording of 1090 km of seismic reflection profiles in a grid over the Boobyalla Sub-basin of the Bass Basin (mainly 10s records, 26.7litre air-gun array). (iv) Shooting of 2 x 200km refraction lines across the central part of the Gippsland basin from Deal Island to the Victorian coast.

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The Joint Development Zone (JDZ) and adjacent areas cruise is part of a program beingundertaken by AGSO, to determine the structural architecture of the northwestern margin ofAustralia and the influence of structuring on the location, migration and trapping ofhydrocarbons in the region. The major objectives of the cruise are: 1) to determine the regional structural framework of the eastern Timor Sea region by examiningthe boundaries between the major structural elements along a series of transects; 2) to provide modern regional seismic tie lines through key wells in the region to facilitateprovince-wide correlations; 3) to determine the deep crustal structure of the Sahul Syncline, Sahul Platform, Timor Troughand Malita Graben; 4) to examine the effects of the deep crustal structure and their various phases of reactivationon the stnitural development of the region. To meet these objectives it is proposed that the R V Rig Seismic collect approximately 2600km of deep crustal (16 sec record length) multichannel seismic and other geophysical data along13 lines in and around the JDZ. The proposed lines tie major wells in the region. Wherepossible the lines are orthogonal to the principal trends in the region. Some strike lines areincluded to assist the regional ties between wells and existing data sets.

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The East Malita cruise is part of a program designed to determine the structural architecture ofthe northwestern margin of Australia and the influence of structuring on the location of,migration and trapping of hydrocarbons in the region. The major objectives of the East MalitaGraben project are: 1) determine the regional structural framework of the eastern Timor Sea region by examiningthe boundaries between the major structural elements along a series of transects; 2) provide modern regional seismic tie lines through the wells in the region to facilitateprovince wide correlations; 3) determine the deep crustal structure of the Malita and Calder Grabens; 4) examine the effects of the deep crustal structure and its reactivation on the location of theknown petroleum accumulations. To examine these problems it is proposed that the R V Rig Seismic be used to collect a total ofapproximately 3000 km of deep crustal multichannel seismic and other geophysical data along 17lines in the East Malita Graben region. The proposed lines tie all 8 wells in the region plusTuatara-1 and Kulka -1 to the east. The lines are designed to examine the major structuralrelationships in the region. Where possible the lines are orthogonal to the principal trends in theregion.

Crustal seismic reflection profiling has successfully imaged the depth extent and the internalstructure of the Archaean greenstone of the Kalgoorlie Terrane and adjacent belts. The basalcontact of the green stones is subhorizontal and gently undulating, reaching a maximum depthof 7 km. Strongly reflective, subhorizontal layering occurs below the basal contact interpretedto be gneissic basement. The basal contact is offset in several places by moderate- to shallow-dipping, strongly reflective zones which project to the surface at the position of previouslymapped shear zones. These shear zones show clear normal displacement of greenstonestratigraphy and the basal greenstone-gneiss; some sole out into the basal greenstone contactand others extend considerably deeper into the gneissic basement. Stratigraphy and major foldstructures are well delineated, and granite plutons have been constrained to tapering surf-board shapes, rather than the sheet-like forms, or diapirs. Stratigraphic units appear totruncate abruptly at the basal greenstone contact in many places suggesting significantdecollement has occurred at the contact during low-angle thrusting. In association with the seismic traverse, a gravity traverse (200m station spacing) and airbornemagnetic traverse were carried out. The geological interpretation of seismic units is usefullyconstrained by the gravity data, which also provide evidence of changes in crustal structurealong the line. Geochemical analysis was carried out on material collected from the bottom of each shot hole(883 samples). A suite of 30 trace elements were analysed, and these data demonstratesignificant differences in granite chemistry along the line. A number of anomalous values for avariety of elements have been identified.

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