From 1 - 10 / 1200
  • The coverage of this dataset is over the Taree region . The C3 LAS data set contains point data in LAS 1.2 format sourced from a LiDAR ( Light Detection and Ranging ) from an ALS50 ( Airborne Laser Scanner ) sensor . The processed data has been manually edited to achieve LPI classification level 3 whereby the ground class contains minimal non-ground points such as vegetation , water , bridges , temporary features , jetties etc . Purpose: To provide fit-for-purpose elevation data for use in applications related to coastal vulnerability assessment, natural resource management ( especially water and forests) , transportation and urban planning . Additional lineage information: This data has an accuracy of 0.3m ( 95 confidence ) horizontal with a minimum point density of one laser pulse per square metre. For more information on the data's accuracy, refer to the lineage provided in the data history .

  • This USB has been produced for promotional purposes and will be handed out (free) at domestic and international conferences. The USB contains a selection of GA reports, flyers, maps and data. Products are grouped into 4 categories: Records and Brochures, Mineral Deposits, Geophysical Data and Surface Geology.

  • Palaeovalley evolution in the Murchison region, Western Australia P. English1 Geoscience Australia, GPO Box 378, Canberra, ACT 2601 Australia. Contact Author: Pauline.English@ga.gov.au The Murchison Province of the Archean Yilgarn Craton, Western Australia, is characterised by intricate networks of palaeovalleys incised into granite-greenstone, that attest to prolonged fluvial activity that began before the break-up of Gondwana. The Murchison region depends on palaeovalley aquifers for water supplies for towns, and mining and pastoral activities. Most of the existing 1000 bores/wells within the district are less than 20 m deep, in calcrete or shallow alluvium, the first having been sunk in Cue township in 1891 to support the Murchison gold rush. Little or no information about underlying alluvial sediments was acquired in the ensuing 120 years and an understanding of the geomorphological evolution of the province is lacking. Current expanding mining for iron ore, gold and other commodities, exacerbated by the recent 10-year drought, has increased demands for water resources, driving the imperative to improve our understanding of these palaeovalleys and their aquifers. Recent regional reconnaissance work by Geoscience Australia has enabled drilling through widespread Murchison palaeovalleys to underlying bedrock, revealing distinctive geomorphic and sedimentary characteristics that contrast considerably with palaeovalleys elsewhere. The Murchison reconnaissance drilling program, funded by the National Water Commission (English et al., 2012), was complemented by acquisition of geophysical data and preliminary hydrogeological investigation. The palaeovalleys have been found to be much deeper than counterparts elsewhere in the Yilgarn. They have incised crystalline bedrock to depths of up to 200 metres, i.e., down to the base level of Kalbarri Gorge, close to the Indian Ocean in the west, whilst depths of 60-120 metres are more typical in other parts of the Yilgarn. Moreover, the distinctive bimodal Eocene-Miocene sedimentation in the well-studied Eastern Goldfields and southern Yilgarn provinces with the dominance of clay strata over coarser-grained alluvium therein, is not replicated in the Murchison region, where coarse sands are prevasive and where preliminary palynological data indicate Pliocene to Pleistocene infilling. Neotectonism and reactivation of erosion and alluviation in the Murchison Province in relatively recent times is suggested by the nature of valley infill and the fact that older palaeovalley sediments have been removed, presumably westwards beyond the edge of the Yilgarn to the coastal plain or Indian Ocean. Radiometric imagery and the abundance of active faults across downstream reaches of the palaeovalleys tend to support such an interpretation. Increased erosion and fluvial sedimentation rates and grain sizes in the Pliocene-Pleistocene may also be attributable to the influence of climate change 2-4 Myr ago such as postulated on the global scale by Peizhen et al. (2001). The great depths of palaeovalleys in the Murchison region and their sandy fluvial infill indicate extensive aquifer systems although the sustainable abstraction of variable quality groundwaters therein will require more thorough investigation and monitoring. References English, P., Lewis, S., Bell, J., Wischusen, Woodgate, M., Bastrakov, E., Macphail, M., Kilgour, P., 2012. Water for Australia's arid zone - identifying and assessing Australia's palaeovalley groundwater resources. National Water Commission: Waterlines Report Series No 86, July 2012. Peizhen, Z., Molnar, P. and Downs, W.R., 2001. Increased sedimentation rates and grain sizes 2-4 Myr ago due to the influence of climate change on erosion rates. Nature 410: 891-897.

  • Development of python-FALL3D: a modified procedure for modelling volcanic ash dispersal in the Asia-Pacific region

  • This dataset reflects the external boundaries of all native title determination and compensation applications that are currently recognized and active within the Federal Court process. Applications that are non-active (i.e. withdrawn, dismissed, finalised, rejected or combined) are only included as aspatial records for completeness. This is a national dataset with data partitioned by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these for completeness. This dataset depicts the spatial definition of active Claimant and Non-claimant native title determination applications and compensation applications. Where possible these may include internal boundaries or areas excluded. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member where assigned to the application. Applications included on the Schedule of Native Title (Federal Court) include all registered and unregistered applications as well as determined applications that are yet to be finalized. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • Observation of the inundation of a scroll-plain of the Darling River during 2010-2011 sheds light on flood processes of an arid zone river where sediments are dominated by sodic smectites. Initial inundation progressed as much by subsurface flow as by surface, with the flow front extending some metres in front of the surface flow, via a network of pipes and cracks. Surface collapse into the cavities was common, however only in the top metre or less was affected. Water rose to 2.5 m above the scroll swales and locally encroached onto an older alluvial terrace to a depth of <0.5 m. Microrelief determined surface flow direction which could be 180o from that in the main channel. Flow crossed the scroll-plain during the flood peak parallel to the trend of the channel belt. The fastest flows deposited ripples of fine sand and coarse silt of quartz and clay pellets. The clay-rich surface of the scroll-plain trapped pools of water in low points such as abandoned channels and swales after the flood fell. Water loss is by evaporation, rather than infiltration. Little or no recharge of the shallow aquifer from the scroll-plain is expected because of this impermeable layer, any recharge must be by lateral groundwater flow. As the surface dried it was broken up by cracking. Deeper cracks are expected to form with drying of the subsoil. The absence of small scale sedimentary structures in the subsurface is explained by a combination of self-mulching and by collapse into cavities. Significant subsurface flow also indicates that sedimentary structures such as ripples, even if preserved, may not have originated on the surface, but in the subsurface.

  • At Geoscience Australia (GA), Australia's Commonwealth Government geoscientific agency, we perform gravity and magnetic modeling at a range of scales, from broad regional crustal studies with thousands of kilometer lateral extent and tens of kilometer vertical extent, to detailed local studies with kilometer or less lateral extent and meters to hundreds of meters vertical extent. To achieve greater integration and coherence, and to better understand the geological significance of this work, we are investing in a number of development projects

  • APREF is a joint effort of the International Association of Geodesy (IAG) and the Permanent Committee for GIS Infrastructure of the Asia-Pacific (PCGIAP) with the objective to increase the density of the International Terrestrial Reference Frame (ITRF) in the Asia-Pacific. In response to the APREF call for participation in March 2010, GNSS data from a Continuously Operating Reference Station (CORS) network of approximately 400 stations, contributed by 30 countries, are currently contributed and processed by three Local Analysis Centres. APREF products, available from http://www.ga.gov.au/earth-monitoring/geodesy/asia-pacific-reference-frame.html, include rapid daily solutions which are produced using IGS rapid products, final daily solutions which are produced using IGS final products, weekly combined solutions and a multi-year cumulative solution. In this poster, the status, challenges and the future plans of APREF are overviewed.

  • A multi spectral spot image was used in a poster that was published by AUSLIG in 1992. This image (not the poster) was then scanned by AGSO on September 4th, 2000. Both TIFF and JPG files exist. This image was created to be used in areas (eg. center of southern atoll) where there was no orthophotography coverage. This TIFF image is best used at a scale no less than 1:50000, zooming in past this results in a pixelated image and a loss of definition.

  • prospectivity of radiogenic granites of the central Arunta Region, Northern Territory