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  • 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 .

  • Hydrogeology of East Timor

  • Removing the topographic effect from satellite images is a very important step in order to obtain comparable surface reflectance in mountainous areas and to use the images for different purposes on the same spectral base. The most common method of normalising for the topographic effect is by using a Digital Surface Model (DSM) and / or a Digital Elevation Model (DEM). However, the accuracy of the correction depends on the accuracy, scale and spatial resolution of DSM data as well as the co-registration between the DSM and satellite images. A physics based BRDF and atmospheric correction model in conjunction with a 1-second SRTM (Shuttle Radar Topographic Mission) derived DSM product released by Geoscience Australia in 2010 were used to conduct the analysis reported in this paper. The results show that artefacts in the DSM data can cause significant local errors in the correction. For some areas, false shadow and over corrected surface reflectance factors have been observed. In other areas, the algorithm is unable to detect shadow or retrieve an accurate surface reflectance factor in the slopes away from the sun. The accuracy of co-registration between satellite images and DSM data is crucial for effective topographic correction. A mis-registration error of one or two pixels can lead to large error of retrieved surface reflectance factors in the gully and ridge areas (retrieved reflectance factors can change from 0.3 to 0.5 or more). Therefore, accurate registrations for both satellite images and DSM data are necessary to ensure the accuracy of the correction. Using low resolution DSM data in conjunction with high resolution satellite images can fail to correct some significant terrain effects. A DSM resolution appropriate to the scale of the resolution of satellite image is needed for the best results.

  • CIMFR_area_under_management.shp: These data show the Christmas Island Minesite to Forest Rehabilitation Programme (CIMFR) areas - as used by staff at the Christmas Island National Park. CIMFR_area_buffer.shp: These data show a 50m buffer zone within the Christmas Island Minesite to Forest Rehabilitation Programme (CIMFR) areas - as used by staff at the Christmas Island National Park.

  • Basins on the western margin of Australia are both well explored (e.g. North West Shelf) or under-explored frontier basins (e.g. Perth Basin). For many of these basins, knowledge of basement and crustal structure is limited. To provide new insight into these fundamental features of a continental margin, we present the results of process-oriented gravity modelling applied to basins both with (North West Shelf) and without (Perth Basin) constraints on crustal structure. Process-oriented gravity modelling is a method that considers the rifting, sedimentation and magmatic processes that led to the present-day gravity field. By back-stripping the sediment load under different assumptions of isostasy (i.e. range of flexural rigidities), rift-related crustal structure can be inferred. When the rift and sedimentation gravity anomalies are combined and compared to observed free-air gravity, insight into the presence of magmatic underplating, the location of the continent-ocean boundary and the thermal history of a margin can, amongst other factors, be gained. Initial modelling suggests that the Perth Basin maintained a relatively low flexural rigidity throughout its history (effective elastic thickness ~5 km), which may reflect the prevalence of transtensional deformation during Late Jurassic-Early Cretaceous break-up between Australia and Greater India. However, constraining elastic thickness in the Perth Basin is made difficult by uncertainties in resolving the total sediment thickness (particularly in outboard parts of the basin) and crustal structure. Such uncertainties are less of an issue for some North West Shelf basins where seismic refraction data enhance the interpretation of abundant seismic reflection data.

  • This database contains the monthly mean and montly long term mean fields from the NCEP/NCAR Reanalysis 1960-2000. Files contain the following data: airsfc.mon.mean.nc - surface air temperature land.nc - land/sea mask slp.mon.mean.nc - sea level pressure sst.mnmean.nc - sea surface temperature (see SST_README for more details) uwnd.mon.mean.nc - U (eastward) component of wind vwnd.mon.mean.nc - V (northward) component of wind shum.mon.mean.nc - specific humidity (this file does not contain all vertical levels, unlike the other 3-d variables) For all the above, files with 'ltm' instead of 'mean' contain the long-term monthly mean data. Data were downloaded on 25/11/2009 from the Earth System Reseach Laboratory (ESRL) Physical Sciences Division (PSD) website. (http://www.esrl.noaa.gov/psd/data/gridded/reanalysis/)

  • The Great Artesian Basin Water Resource Assessment (the Assessment) provides an analytical framework to assist water managers in the Great Artesian Basin (GAB) to meet National Water Initiative commitments. This report presents the findings of the Assessment for the Surat region - one of four reporting regions in the Assessment, including the Surat, Central Eromanga, Western Eromanga and Carpentaria regions.

  • Geomorphic landscape features and associated surface materials are fundamental to groundwater recharge processes as they form the first layer through which surface water passes before it becomes groundwater. Different surface materials exhibit different water-holding capacity and hence permeability characteristics. In the Broken Hill Managed Aquifer Recharge project, surface-materials mapping in conjunction with geomorphic mapping, has assisted hydrogeological investigations, including recharge predictions, salinity hazard and the identification of potential infiltration basins. Prior to landform identification, LiDAR DEM data was levelled using trend surfaces to eliminate regional slope (~20m). As a consequence of this, an ArcGIS interactive contour tool could be used to identify specific breaks in elevation associated with landform features. Multivariate image analysis of elevation, high resolution SPOT and Landsat-derived wetness further enhanced the contrast between geomorphic elements to confirm mapping boundaries. While specific landforms can be characterised by particular surface materials, these sediments can vary within a single geomorphic feature. Consequently, SPOT multispectral satellite imagery was used to identify surface materials using principal component analysis and unsupervised classification. This approach generated 20 classes; each assigned a preliminary cover/landform attribute using SPOT imagery. Field data (surface and borehole sample, and observations at shallow pits) were used to refine the classification approach. Interactive mapping using a de-trended DEM provided a rapid, effective and accurate alternative to time consuming manual landform digitisation. The combination of these two new products - surface-materials and geomorphic maps - has assisted in the identification of potential recharge sites and naturally occurring infiltration sites.

  • The under-explored deepwater Otway and Sorell basins lie offshore of southwestern Victoria and western Tasmania in water depths of 100-4,500 m. The basins developed during rifting and continental separation between Australia and Antarctica from the Cretaceous to Cenozoic and contain up to 10 km of sediments. Significant changes in basin architecture and depositional history from west to east reflect the transition from a divergent rifted continental margin to a transform continental margin. The basins are adjacent to hydrocarbon-producing areas of the Otway Basin, but despite good 2D seismic data coverage, they remain relatively untested and their prospectivity is poorly understood. The deepwater (>500 m) section of the Otway Basin has been tested by two wells, of which Somerset 1 recorded minor gas shows within the Upper Cretaceous section. Three wells have been drilled in the Sorell Basin, where minor oil and gas indications were recorded in Maastrichtian rocks near the base of Cape Sorell 1. Building on previous GA basin studies and using an integrated approach, new aeromagnetic data, open-file potential field, seismic and exploration well data have been used to develop new interpretations of basement structure and sedimentary basin architecture. Analysis of potential field data, integrated with interpretation of 2D seismic data, has shown that reactivated north-south Paleozoic structures, particularly the Avoca-Sorell Fault System, control the transition from extension through transtension to a dominantly strike-slip tectonic regime along this part of the southern margin. Depocentres to the west of this structure are large and deep in contrast to the narrow elongate depocentres to its east. Regional-scale mapping of key sequence stratigraphic surfaces across the basins has resulted in the identification of distinct basin phases. Three periods of upper crustal extension can be identified. In the north, one phase of extension in the Early Cretaceous and two in the Late Cretaceous can be mapped. However, to the south, the Late Cretaceous extensional phase extends into the Paleocene, reflecting the diachronous break-up history. Extension was followed by thermal subsidence, and during the Eocene-Oligocene the basin was affected by several periods of compression, resulting in inversion and uplift. The new seismic interpretation shows that depositional sequences hosting active petroleum systems in the producing areas of the Otway Basin are also likely to be present in the southern Otway and Sorell basins. Petroleum systems modelling suggests that if the equivalent petroleum systems elements are present, then they are mature for oil and gas generation, with generation and expulsion occurring mainly in the Late Cretaceous in the southern Otway and northern Sorell basins and during the Paleocene in the Strahan Sub-basin (southern Sorell Basin). The integration of sequence stratigraphic interpretation of seismic data, regional structural analysis and petroleum systems modelling has resulted in a clearer understanding of the tectonostratigraphic evolution of this complex basin system. The results of this study provide new insights into the geological controls on the development of the basins and their petroleum prospectivity.