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  • The Secondary Coastal Sediment Compartment data set represents a sub-regional-scale (1:100 000 - 1:25 000) compartmentalisation of the Australian coastal zone into spatial units within (and between) which sediment movement processes are considered to be significant at scales relevant to coastal management. The Primary and accompanying Secondary Coastal Sediment Compartment data sets were created by a panel of coastal science experts who developed a series of broader scale data sets (Coastal Realms, Regions and Divisions) in order to hierarchically subdivide the coastal zone on the basis of key environmental attributes. Once the regional (1:250 000) scale was reached expert knowledge of coastal geomorphology and processes was used to further refine the sub-division and create both the Primary and Secondary Sediment Compartment data sets. Environmental factors determining the occurrence and extents of these compartments include major geological structures, major geomorphic process boundaries, orientation of the coastline and recurring patterns of landform and geology - these attributes are given in priority order below. 1 - Gross lithological/geological changes (e.g. transition from sedimentary to igneous rocks). 2 - Geomorphic (topographic) features characterising a compartment boundary (often bedrock-controlled) (e.g. peninsulas, headlands, cliffs). 3 - Dominant landform types (e.g. large cuspate foreland, tombolos and extensive sandy beaches versus headland-bound pocket beaches). 4 - Changes in the orientation (aspect) of the shoreline.

  • The Brattstrand Paragneiss, a highly deformed Neoproterozoic granulite-facies metasedimentary sequence, is cut by three generations of ~500 Ma pegmatite. The earliest recognizable pegmatite generation, synchronous with D2-3, forms irregular pods and veins up to a meter thick, which are either roughly concordant or crosscut S2 and S3 fabrics and are locally folded. Pegmatites of the second generation, D4, form planar, discordant veins up to 20-30 cm thick, whereas the youngest generation, post-D4, form discordant veins and pods. The D2-3 and D4 pegmatites are abyssal class (BBe subclass) characterized by tourmaline + quartz intergrowths and boralsilite (Al16B6Si2O37); the borosilicates prismatine, grandidierite, werdingite and dumortierite are locally present. In contrast, post-D4 pegmatites host tourmaline (no symplectite), beryl and primary muscovite and are assigned to the beryl subclass of the rare-element class. Spatial correlations between B-bearing pegmatites and B-rich units in the host Brattstrand Paragneiss are strongest for the D2-3 pegmatites and weakest for the post-D4 pegmatites, suggesting that D2-3 pegmatites may be closer to their source. Initial 87Sr/86Sr (at 500 Ma) is high and variable (0.7479-0.7870), while -Nd500 tends to be least evolved in the D2-3 pegmatites (-8.1 to -10.7) and most evolved in the post-D4 pegmatites (-11.8 to -13.0). Initial 206Pb/204Pb and 207Pb/204Pb and 208Pb/204Pb ratios, measured in acid-leached alkali feldspar separates with low U/Pb and Th/Pb ratios, vary considerably (17.71-19.97, 15.67-15.91, 38.63-42.84), forming broadly linear arrays well above global Pb growth curves. The D2-3 pegmatites contain the most radiogenic Pb while the post-D4 pegmatites have the least radiogenic Pb; data for D4 pegmatites overlap with both groups. Broad positive correlations for Pb and Nd isotope ratios could reflect source rock compositions controlled two components. Component 1 (206Pb/204Pb-20, 208Pb/204-43, Nd -8) most likely represents old upper crust with high U/Pb and very high Th/Pb. Component 2 (206Pb/204Pb -18, 208Pb/204Pb~38.5, -Nd500 -12 to -14) has a distinctive high-207Pb/206Pb signature which evolved through dramatic lowering of U/Pb in crustal protoliths during the Neoproterozoic granulite-facies metamorphism. Component 1, represented in the locally-derived D2-3 pegmatites, could reside within the Brattstrand Paragneiss, which contains detrital zircons up to 2.1 Ga old and has a wide range of U/Pb and Th/Pb ratios. The Pb isotope signature of component 2, represented in the 'far-from-source' post-D4 pegmatites, resembles feldspar Pb isotope ratios in Cambrian granites intrusive into the Brattstrand Paragneiss. However, given their much higher 87Sr/86Sr, the post-D4 pegmatite melts are unlikely to be direct magmatic differentiates of the granites, although they may have broadly similar crustal sources. Correlation of structural timing with isotopic signatures, with a general sense of deeper sources in the younger pegmatite generations, may reflect cooling of the crust after Cambrian metamorphism.

  • The `Isotopic Domain Boundaries of Australia data set is based on an interpretation of the recently released Neodymium depleted mantle model age map of Australia (GA Record 2013/44). The isotopic map of Australia was produced by gridding two-stage depleted mantle model ages calculated from Sm-Nd isotopic data for just over 1490 samples of felsic igneous rocks throughout Australia. The resultant isotopic map serves as a proxy for bulk crustal ages and accordingly allows the recognition of possible geological domains with differing geological histories. One of the major aims of the Neodymium depleted mantle model age map, therefore, was to use the isotopic map (and associated data) to aid in the recognition and definition of crustal blocks (geological terranes) at the continental and regional scale. Such boundaries are recognisable by regional changes in isotopic signature but are hindered by the variable and often low density of isotopic data points. Accordingly two major procedures have been adopted to locate the regional distribution of such boundaries across the continent. In areas of higher data density (and high confidence), such as the Yilgarn Craton of Western Australia, isotopic data alone was used to delineate crustal domains. In areas of moderate data density (and corresponding moderate confidence) (smoothed) boundaries of known geological provinces were used as a proxy for the isotopic boundary. For both high and moderate data densities identified crustal boundaries were extended (with corresponding less confidence) into regions of lower data density. In areas of low data density (and low confidence) boundaries were either based on other geological and/or geophysical data sets or were not attempted. The latter was particularly the case for regions covered by thick sedimentary successions. Two levels of confidence have been documented, namely the level of confidence in the location of the isotopic domain boundary, and the level of confidence that the boundary is real. The `Isotopic Domain Boundaries of Australia map shows the locations of inferred boundaries of isotopic domains, which are assumed to represent the crustal blocks that comprise the Australia continent. The map therefore provides constraints on the three dimensional architecture of Australia, and allows a better understanding of how the Australian continent was constructed from the Mesoarchean through to the Phanerozoic. It is best viewed as a dynamic dataset, which will need to be refined and updated as new information, such as new isotopic data, becomes available.

  • Whether rift basins form as a consequence of pure shear or simple shear stretching of the lithosphere or a hybrid of these two end members has long been the focus of debate (McKenzie, 1978; Wernicke, 1985; Rosenbaum et al., 2008). It is generally accepted that under low strain pure shear dominates yet the debate rages with respect to highly extended continental margins. The key dataset to resolve this debate is the spatial distribution of syn-rift and post-rift basin subsidence resulting from mechanical thinning of the lithosphere and subsequent thermal re-thickening of the lithospheric mantle to its pre-rift thickness. An often-overlooked element of this debate is what lithospheric template is being stretched (Crosby et al., 2010). Most geodynamic models simply assume a standard lithospheric thickness of 100120 km, yet in the last decade teleseismic tomography has revealed that much of the Earth's continental land mass is underlain by lithosphere over double this thickness (Priestley and McKenzie, 2013). Here, we kinematically model the subsidence history of the Canning basin following Crosby et al. (2010). This intracratonic rift basin putatively overlies lithosphere 180 km thick, imaged using shear wave tomography (Kennett et al., 2013). The entire subsidence history of the, < 300 km wide and < 6 km thick, western Canning Basin is adequately explained by Ordovician rifting of pre-existing 100120 km thick lithosphere followed by post-rift thermal subsidence as described by the established pure shear model. In contrast, the < 150 km wide and 15 km thick Fitzroy Trough of the eastern Canning Basin reveals an almost continuous phase of normal faulting between Ordovician and Carboniferous Periods followed by negligible post-rift thermal subsidence. This pattern cannot be accounted for by a simple shear model (c.f. Drummond et al., 1991), as there is no record of excess post-rift subsidence in the basin, nor does the data fit the standard pure shear model. We attribute this difference in subsidence to a sharp change in mantle lithospheric thickness between the west and eastern Canning Basin. The presence of ~20 Ma diamond bearing lamproites intruded into the basin depocentre indicate that the present lithospheric thickness exceeds ~180 km (Evans et al., 2012). In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted by 5070 kg m3. The actual depletion of the lowermost lithospheric mantle was assessed by modeling REE concentrations of the ~20 Ma lamproites along with other ultrapotassic rocks from the Kimberley, Yilgarn and Pilbara blocks following the method of Tainton and McKenzie (1994) which reveal a depletion of 4070 kg m3. This result suggests that thermal re-thickening of the lithospheric mantle did not occur following rifting, as it is unlikely that such a strongly depleted mantle source was available in the Phanerozoic to be frozen into the lowermost lithospheric mantle. Therefore, we conclude that thinning of thick lithosphere to thicknesses > 120 km is thermally stable and is not accompanied by post-rift thermal subsidence driven by thermal re-thickening of the lithospheric mantle. The discrepancy between estimates of lithospheric thickness derived from subsidence data in the Western Canning and that derived from shear wave tomography suggests that the latter technique cannot resolve lithospheric thickness variations on < 300 km half wavelengths.

  • The National Computational Infrastructure (NCI) at the Australian National University (ANU) has co-located a priority set of over 10 PetaBytes (PBytes) of national data collections within a HPC research facility. The facility provides an integrated high-performance computational and storage platform, or a High Performance Data (HPD) platform, to serve and analyse the massive amounts of data across the spectrum of environmental collections in particular from the climate, environmental and geoscientific domains. The data is managed in concert with the government agencies, major academic research communities and collaborating overseas organisations. By co-locating the vast data collections with high performance computing environments and harmonising these large valuable data assets, new opportunities have arisen for Data-Intensive interdisciplinary science at scales and resolutions not hitherto possible.

  • Updated USB drive containing GA-reports, maps, and flythroughs (2008-2015) in digital format to be handed out as promotional material at AMSA 2015 conference.

  • The purpose of this study was to constrain the processes of Paleoproterozoic crustmantle evolution by investigating the Lu-Hf, Sm-Nd and oxygen isotope systematics of igneous rocks of the Lamboo Province of the Halls Creek and King Leopold Orogens, in the Kimberley region of Western Australia. The specific objectives were to: 1. Ascertain the nature of the source rocks of the granites, and to test whether granite formation involved the reworking of ancient meta-igneous protoliths in an intra-plate environment or complex crust-mantle interaction processes typical of modern plate tectonic settings; 2. Use data from granite-hosted zircons to quantify the proportion of new crust formed during discrete magmatic events, and to link this with the longer-term record of crustal evolution preserved by detrital zircons, and 3. Constrain the tectonic setting of the Lamboo Province, and thus the geodynamic controls on global crustal growth in this key time period.

  • B-Roll footage showing a visualisation of the 4 earthquakes above a magnitude of 5 in QLD, Australia in 2015, as of August that year. Each quake is shown as expanding Radii, coloured as per the MMI for the magitude of the quake, representing the expected radius that the quake can be felt, to MMI 3.

  • chapter submission (ch. 6) for the ISPRS Manual for Remote Sensing v4

  • Data for the collaborative project with the South Australian Department of Environment, Water and Natural Resources (DEWNR)