Geoscience Australia in collaboration with the Geological Survey of Western Australia (Royalties for Regions Exploration Incentive Scheme), the Department of State Development South Australia and AuScope funded the Eucla-Gawler 2D deep seismic survey. The seismic survey acquisition and processing were managed and processed by Geoscience Australia. Geokinetics Australasia Ltd were contracted to collect the Eucla-Gawler 2D deep seismic reflection survey from November 2013 to February 2014. Deep seismic reflection data and gravity readings were acquired along the 834 km seismic line. Magnetotelluric (MT) data (Duan et al, 2015) were also acquired along the seismic line after the completion of the seismic survey. The main objectives of the project are to acquire deep crustal seismic data to (Geoscience Australia, 2013): (1) Image the crustal architecture of the geology underlying the Eucla Basin and its relationship to the Gawler Craton to the east and the Yilgarn Craton to the west; (2) Establish the subsurface extent of the Eucla Basin and look for large structural zones that may have provided fluid pathways for mineralisation.

Diagram produced for the Department of Industry and Science to depict those areas of water adjacent to SA that fall under the OPGGS Act, Petroeum (Seas and Submerged Lands) Act 1982 (SA) and Petroleum and Geothermal Energy Act 2000 (SA).

Airborne LiDAR data was acquired over Adelaide in September 2008 and North Adelaide in September 2011. Differences in the level of classification reduced the ability to integrate the data into an accurate, seamless and consistent coastal DEM suitable for detailed modelling the potential impacts of coastal inundation or riverine flooding. The objective of this project was to reclassify both the 2008 and 2011 point clouds to ICSM Level 3 and derive hydro flattened 1m bare earth DEMs and; 0.25m cartographic contours, all inline with the ICSM LiDAR Acquisition Specifications.

The Coompana Province is one of the most poorly understood pieces of crystalline basement geology in the Australian continent. It lies entirely concealed beneath a variable thickness of Neoproterozoic to Cenozoic sedimentary rocks, and is situated between the Gawler Craton to the east, the Musgrave Province to the north, and the Madura and Albany-Fraser Provinces to the west. A recently-acquired reflection seismic transect (13GA-EG1) provides an east-west cross-section through the southern part of the Coompana Province, and yields new insights into the thickness, seismic character and gross structural geometry within the Coompana Province. To assist geological interpretation of the 13GA-EG1 seismic line, new SHRIMP U-Pb zircon ages have been acquired from samples from the limited drill-holes that intersect the Coompana Province. New results from several granitic and gneissic rocks from the Coompana Province yield magmatic and/or high-grade metamorphic ages in the interval 1100 1200 Ma. Magmatic or high-grade metamorphic ages in this interval have not been identified in the Gawler Craton, in which the last major magmatic and metamorphic event took place at ~1590 1570 Ma. The Gawler Craton was largely unaffected by ~1100 1200 Ma events, as evidenced by the preservation of pre-1400 Ma 40Ar/39Ar cooling ages. In contrast, magmatic and metamorphic ages of 1100 1200 Ma are characteristic of the Musgrave Province (Pitjantjatjara Supersuite) and Madura Province (Moodini Supersuite). The new results from the Coompana Province have also yielded magmatic or inherited zircon ages at ~1500 Ma and ~1640 Ma. Once again, these ages are not characteristic of the Gawler Craton and no pre-1700 Ma inherited zircon has been identified in Coompana Province magmatic rocks, as might be expected if the province was underlain by older, Gawler Craton-like crust. The emerging picture from this study and recent work from the Madura Province and the Forrest Zone of the western Coompana Province is that the Coompana Province has a geological history that is quite distinct from, and generally younger than, the Gawler Craton to its east, but that is very similar to the Musgrave and Madura Provinces to the north and west. The contact between the Coompana Province and the Gawler Craton is interpreted in the 13GA-EG1 seismic line as a prominent west-dipping crustal-scale structure, termed the Jindarnga Shear Zone. The nature and timing of this boundary remain relatively poorly constrained, but the seismic and geochronological evidence suggests that it represents the western edge of the Gawler Craton, marking the western limit of an older, more isotopically evolved and multiply re-worked craton to the east, from a younger, more isotopically primitive crust that separates the South Australian Craton from the West Australian Craton.

From a study of middle to late Eocene calcareous nannofossil assemblages in four sections in the Otway Basin of southeastern Australia, a sequence of biostratigraphic events has been deduced, spanning the interval from the lowest appearance of Cyclicargolithus reticulatus (middle Eocene) to the disappearance of Discoaster saipanensis (latest Eocene). The sequence is compared with its coumerpart in New Zealand, and is placed against the planktic foraminiferal P. zones of the tropics. The previously determined foraminiferal biostratigraphy of the sections studied has been compared with the nannofossil biostratigraphy, and, as a result, the local highest appearance of the foraminiferid Acarinina primitiva is now placed in zone P. l3 of the tropics , and not P.12 or P.14, as previously. The disappearance up the section of the foraminiferid Acarinina collactea is found to be locally inconsistent with other evidence. During the middle Eocene, marine ingressions, represented by isolated nannofossil assemblages, occurred in the Gambier Embayment of the western Otway Basin, but did not reach the Browns Creek area, eastern Otway Basin, attesting to the diachroneity of Eocene marine sedimentation in the basin . The diachroneity is also indicated by transgressive rock units in the Gambier Embayment. The ingressions seem to coincide with a major change in the sea-floor spreading rate south of Australia. During the latest middle to early late Eocene, a major transgression began synchronously in widely separated areas across the basin. The upper Eocene section in the Gambier Embayment represents condensed sedimentation and ends in a sharp disconformity, indicated by the simultaneous disappearance of Cyclicargolithus reticulatus and Discoaster saipanensis. At Browns Creek, that part of the section between the highest appearances of C. reticulatus and D. saipanensis is thick, suggesting relatively rapid rates of sedimentation. However, in the expanded part of the section at Browns Creek and also at Castle Cove, there is evidence that extreme shoal conditions existed as a result of imbalance between sedimentation and subsidence. During the middle and late Eocene, conditions along the Australian southern margin were generally temperate, with surface-water temperature decreasing eastward, and the depositional environment was essentially shallow marine - nearshore or shelf.

Desert varnish coatings rich in manganese are reported, to the authors knowledge , for the first time on desert rocks from Australia. Varnish was found on chert, dolomite, sandstone, siltstone, and conglomerate rocks in stony pave men Is of the Gibson Desert and the Great Victoria Desert of Western Australia and South Australia. The widespread occurrence of desert pavements in Australia suggests that desert varnish, also, may be widespread. Fungi that form microcolonies have been found on rocks with desert varnish. Manganese was found in higher concentrations inside some of the microcolonies than in the surrounding substrate, suggesting that microcolonial fungi are involved in the formation of desert rock varnish in these areas.

Lake Eliza is a hypersaline coastal lake in southeast South Australia, a region of winter rainfall and summer drought. It is fed by ground waters and has no connection with the sea. Salinity rises from < 100 in winter to > 360%() in summer, with accompanying fall in lake level. The lake contains a biota of generally non-marine lineage. Two areas of the lake margin exposed in summer were studied. One, on the western shore, was protected from prevailing winds, the other, on the eastern shore was exposed to wave attack. The western shore is an area of fine carbonate sediments with high organic content. The eastern shore is an area of moderately sorted quartz-carbonate sand of lower organic content. The sediments of Lake Eliza are similar to some of those described from the Wilkins Peak Member of the Green River Formation, USA, and a comparison between the two systems suggests that the lamosite oil shales of the type found in the Green River Formation may not have been deposited in a fresh to brackish lake floor as has been supposed, but could have formed beneath cyanobacterial mats along a protected margin of a saline lake, in a setting equivalent to the western margin of Lake Eliza.

Pseudotachylite vein-breccia networks and pseudotachylites intrafoliated with mylonites occur pervasively in the Tomkinson Ranges, western Musgrave Block, central Australia, about 50 km south and constituting part of the hanging wall of the Woodroffe thrust. The pseudotachylites are almost exclusively confined to gabbro, anorthosite and dolerite, and are rarely seen in basic granulites, felsic granulites and granitic gneiss. Pseudotachylite is ubiquitous in steeply tilted, deformed and mylonite-intersected sectors of the Giles Complex (Hinckley Range, Kalka, Michael Hills) but was not detected in the mildly tilted and little deformed western sectors of the Giles Complex (Blackstone Range, Cavenagh Range, Jameson Range), suggesting that fusion events concentrated in deformed relatively deep crustal levels. Two principal modes of occurrence of pseudotachylite are recognised : 1, vein-breccia networks superimposed on older lithological contacts and associated with brittle fracture systems; 2, penetrative pseudotachylite laminae interleaved with mylonite along shear zones. It is inferred that friction fusion events triggered by seismic faulting have affected intermediate crustal levels where mylonite shears separate brittle fracture domains. Contemporaneous development of pseudotachylite in each domain may be suggested by the lack of observed intersecting relationships between the two types of pseudotachylite vein systems. Alternatively, the mylonite-related pseudotachylites may have formed in quasi-plastic deep crustal zones. Comparisons between the chemistry of pseudotachylites and bulk host rock composition suggest a limited degree of selective fusion, increasing the silica levels and lowering the Mgvalues and Cr levels in the melt. Alternatively, these variations may have been brought about by fluid phase activity. Evidence for a high temperature melt origin of the pseudotachylite includes finer-grained margins, resorbed microclasts, micron-scale subhedral crystal texture of the pseudotachylite and distinct chemistry of microphenocrysts compared with host rock mineral composition. Laser-Raman spectroscopy has shown that the material is mostly crystalline but also suggests the occurrence of minor glass components in the pseudotachylite. High-Al and high-K pyroxenes from the pseudotachylite suggest seismic overpressures of the order of 30 kb, or metastable disequilibrium quench crystallisation of the pseudotachylite melt.

Seismic exploration throughout the Eromanga Basin has identified several regionally-extensive seismic reflection horizons. The C horizon, at the boundary of the Wallumbilla and Cadna-owie Formations, is one of the most significant. A difference in the petrophysical properties of these two formations is evident from sonic, density, gamma ray and resistivity well log data, and indicates that the amplitude of the C horizon reflection is related to a sequence of low-density (undercompacted) shales in the basal part of the Wallumbilla Formation. The properties of the shales appear to be a consequence of rapid subsidence (undercompaction) and burial. The empirical relationships between the C horizon reflection amplitude, formation density and reflection coefficient are discussed, and geological implications for petroleum prospectiveness of the Eromanga Basin are outlined.

The Bremer Basin underlies part of the upper continental slope of offshore southwest Australia. It occupies an area of 9000 km2, and contains a sedimentary pile probably 10 km thick in water depths of 200-3000 m. Though not tested by drilling, the basin is covered by a grid of seismic data. By analogy with the Eyre Sub-basin to the east, the Bremer Basin probably contains Late Jurassic to Barremian continental deposits overlain by Albian and Late Cretaceous marine deposits with a veneer of Tertiary open-marine carbonates of variable thickness. The Bremer Basin formed during the period of continental extension that preceded the breakup of Australia and Antarctica in the mid-Cretaceous. However, Triassic (?and older) extension and spreading events in the Perth Basin, a short distance to the west, are likely to have influenced its evolution. Basement structural trends in the basin indicate an old east-west-trending (?Palaeozoic) fabric that has been overprinted by north-northwesterly oriented Jurassic-Cretaceous extension and wrenching. The resultant structure is complex, particularly where the Palaeozoic and Mesozoic trends intersect. The hydrocarbon potential of the Bremer Basin is currently unknown. However, by analogy with the Eyre Sub-basin, potential source and reservoir sections can be inferred to exist, although the presence of a regional seal and a heatflow regime adequate for the generation of hydrocarbons is less certain. Potential trapping mechanisms for hydrocarbons include wrench-induced anticlines, clastic aprons adjacent to boundary and transfer faults, and stratigraphic traps within dipping Neocomian rocks beneath a major angular unconformity.