These datasets cover approximately 3360 sq km of coastal areas of Northern and South-eastern Tasmania. The project covered three areas: - Greater Hobart 1283 square km - Huon Valley 460 square km - Launceston, Burnie, Devonport 1612 square km This project, undertaken by RPS Mapping on behalf of Geoscience Australia produced accurate LiDAR and derived products to ICSM specifications and medium format digital ortho-photo mosaics.

Compilation of new and existing data can be used to show systematic variations in initial ore-related Pb isotope ratios and derived parameters for the Lachlan and Delamerian orogens of southeast Australia. In addition to mapping tectonic boundaries and providing genetic context to mineralising processes, these variations map mineralised provinces at the orogenic scale and can provide vectors to ore at the district scale. In New South Wales and Victoria, mapping using a parameter termed the 'Lachlan Lead Index' (LLI), which measures relative mixing between crustal- and mantle-derived Pb using the curves of Carr et al. (1995, Economic Geology 90:14671505), clearly demarcates the boundary between the Eastern and Central Lachlan provinces, and seems to identify boundaries between zones within the Western Lachlan Province of Victoria. The LLI also maps the extent of the isotopically juvenile Macquarie 'Arc' in New South Wales. However, rocks in the Rockley-Gulgong Belt, initially mapped as part of the Macquarie Arc, have a more evolved isotopic character, suggesting that these rocks are not part of the Macquarie Arc. This interpretation supports recent mapping that casts doubt on the attribution of this belt to the Macquarie Arc (Quinn, et al., 2014, Journal of the Geological Society of London 171:723736). The LLI has also identified small exposures of Ordovician volcanic rocks, well removed from the main Macquarie Arc, as possible correlates to this arc, with potential to host porphyry and epithermal deposits. Metallogenically, porphyry Cu-Au deposits in the Macquarie Arc are characterised by juvenile Pb. In contrast, Sn and Mo deposits in the Central Lachlan Province (i.e., the Wagga tin belt) are characterised by highly evolved Pb even though these deposits formed over 30 million years. Moreover, the Pb isotope data suggest that the original interpretation that copper deposits in the Girilambone district are volcanic-associated massive sulfide deposits was correct and that these deposits formed in a back-arc to the Macquarie Arc at ~480 Ma. In the Mount Read Volcanics of western Tasmania, all deposits appear to cluster along the same growth curve. However, when divided according to age (i.e., Cambrian (~500 Ma) versus Devonian (~360 Ma)), spatial patterns are visible in 206Pb/204Pb data. For Cambrian deposits 206Pb/204Pb decreases overall to the southeast, although low values are also present in the far south (i.e., Elliott Bay) and northeast. The most highly mineralised central part of the belt seems to be broadly associated with the zone of highest 206Pb/204Pb. Variations in 206Pb/204Pb for Devonian deposits broadly mimic the patterns seen for the Cambrian deposits. More importantly, a district-scale pattern in 206Pb/204Pb is present in the Zeehan district. Isotopically, the Sn-dominated core of the Zeehan district (e.g. Queen Hill and Severn deposits) is characterised by high 206Pb/204Pb, which decreases outward into the Zn-Pb-Ag-dominated peripheries. Lead isotope distribution patterns can potentially be used as an ore vector in this and other intrusion-centered mineral systems.

The Otway Basin is a rifted margin basin containing a sequence of Mesozoic to Tertiary sediments up to 7500 m thick, resting on a Palaeozoic metasedimentary and granitic basement. Hydrocarbon shows are common throughout the basin, the most significant occurrences being small gas fields in basal upper Cretaceous sandstone in the eastern part of the basin, one of which is in commercial production, and a 3 m oil column in Lindon 1 in basal Tertiary sandstone in the central basin area. A lack of commercial oil discoveries in twenty-five years of active exploration and the small size of the known gas fields, together with uncertainty about source rock quality and maturation levels, have tended to downgrade the petroleum potential of the Otway Basin. Geochemical data, mainly from the Cretaceous sequence, indicate that both Upper and Lower Cretaceous rocks have fair quality gas source potential. Some thin beds of oil-prone source rocks may be present, mainly in the Lower Cretaceous and lower Tertiary sequences. Cretaceous structural development appears to have exerted a strong control on maturation throughout the basin. Hydrocarbons formed early in the basins history are unlikely to have been preserved.

New earthquake risk maps of Tasmania have been prepared depicting risk by contours of peak ground velocity, acceleration and intensity with a 10 per cent probability of being exceeded in a 50 year period. The Cornell- McGuire method was used. The maps are based on seismicity up to the end of 1984, including the events of the 1883-1892 earthquake swarm east of Flinders Island and other historical data. The earthquake process was assumed to be Poissonian, so foreshocks and aftershocks were eliminated from the analysis. For this earthquake risk assessment, average eastern Australian background seismicity and attenuation for average site conditions were used. The earthquake source zones most affecting the risk in the Tasmanian region are the West Tasman Sea Zone and the Western Tasmanian Zone. The West Tasman Sea Zone, east of Flinders and Cape Barren Islands, appears to have been the site of the 1883 - 1892 swarm, with at least three intensity-deduced Richter magnitude 6.0- 7.0 events. Consequently, the highest risk land areas are Flinders and Cape Barren Islands, which lie predominantly between the 60 mm.s-1/0.6 m.s-2 and 120 mm.s-1/ 1.2 m.s-2 contours, with the risk increasing to the east. In the Western Tasmanian Zone, the largest event recorded was in 1880. It had an intensity-deduced Richter magnitude of 5.5. The northern part of western Tasmania (enclosed by the 59 mm.s-1/ 0.55 m-2 contour) is the second highest risk region. At Hobart and Launceston, outside the source zones, the values are 23 mm-1 / 0.21 m.s-2 and 30 mm.s-1/ 0.29 m.s-2 respectively, corresponding to a 10 per cent chance of an intensity MMIV - V being exceeded in a 50-year period. However, it appears that site amplification of strong ground motion takes place in some parts of Launceston, and this should be considered when zoning for the Building Code. The chief contributions to uncertainty in the estimates of earthquake risk are uncertainties in early earthquake locations and magnitudes, and in strong ground motion attenuation.

Interpretation of high-quality seismic reflection data from Bass Basin, southeastern Australia, has led to the recognition of major Early Cretaceous extensional normal faults segmented by contemporaneous transfer faults. The normal faults, which initiated development of the basin, are rotational, have low to moderate dips, and were produced by 60-80% horizontal extension (B = 1.6-2.0) of the crust beneath the basin. There are three major normal faults, with trends of 290° to 300° - one along each margin and one near the centre of the basin. The transfer fault s are vertical and trend 0200 to 030°. They are predominantly of right-lateral offset, giving rise to the northwesterly trend of the basin. The normal faults and associated tilt-block edges have had a major influence on structural evolution in the overlying hydrocarbon-prospective Eastern View Coal Measures (EVCM). A play concept is presented that relates the mid-basin tilt-block/normal fault system and associated transfer faults to structures, facies variations, and source maturity within the EVCM. A geohistory analysis of a specific location containing such a structure associated with possible direct hydrocarbon indicators shows that the lower EVCM has been oil-mature since the Oligocene, and it is suggested, therefore, that the prospectivity of the Bass Basin should be upgraded.

Relationships, thicknesses, and palaeocurrent and other sedimentary data applying to facies associations in Eumeralla Formation outcrops in the eastern Otway Basin distinguish at least three discrete depositional systems (A-C). Each system is characterised by high-energy fluvial flows in broad channel tracts. The multistorey sandstone bodies of system A, between Cape Otway and Apollo Bay, are up to 70 m thick and contain varying proportions of basement-derived quartzose gravel and sand intermixed with mainly volcaniclastic sand. Interchannel siltstones also up to 70 m thick separate the sandstone bodies. Palaeocurrents in system A have an overall southerly trend. This system is interpreted to represent deposition in a medial alluvial fan to proximal braided-stream system. System B occurs around Moonlight Head, and may extend southeast to Rotten Point. It is characterised by multistorey sandstone bodies up to 14 m thick separated by siltstones of similar thickness which locally contain thin coal beds, rooted horizons, and reddened soil profiles. It lacks basement-derived gravel. Palaeocurrents trend north-easterly to northwesterly. The sediments of system B accumulated on a medial to distal braid plain. Facies associations and fluvial architecture of system C, seen in outcrop north of Skenes Creek, resemble those of system B, from which it is distinguished by consistently northwest palaeocurrent vectors, a basement-derived gravel component, and the absence of debris flows and volcanic pebbles. System C also represents deposition on a braid plain or in a braided-river system. The three depositional systems are accommodated in a model for the Eumeralla Formation which suggests that its volcanic detritus was derived largely from infrarift volcanic complexes in the axial parts of the Otway rift basin, which during the Aptian-Albian lay to the south of the present coastline. A volcaniclastic apron spread northwest to northeast across the basin (system B). Elevated basement blocks shed quartzose detritus into flanking alluvial fans, the more distal parts of which mixed with volcaniclastic detritus (systems A, C). The onset of axial volcanism in the Aptian may have displaced a former westerly axial drainage towards the northern basin margin (system C).