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  • This dataset maps the geomorphic habitat environments (facies) for 52 Victorian coastal waterways. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Most of the 52 coastal waterways have a "Modified" environmental condition (as opposed to "Near Pristine"), according to the National Land and Water Resources Audit definition.

  • This paper was presented at the Specialist Group in Structural Geology & Tectonics field meeting, Kalbarri, Western Australia, September, 2003

  • Product Specifications Coverage: Partial coverage, predominantly in northern Australia, along major transport routes, and other selected areas. About 1000 maps have been published to date. Currency: Ranges from 1968 to 2006. Coordinates: Geographical and UTM. Datum: AGD66, new edition WGS84; AHD. Projection: Universal Transverse Mercator UTM. Medium: Paper, flat copies only.

  • Product Specifications Coverage: Partial coverage, predominantly in northern Australia, along major transport routes, and other selected areas. About 1000 maps have been published to date. Currency: Ranges from 1968 to 2006. Coordinates: Geographical and UTM. Datum: AGD66, new edition WGS84; AHD. Projection: Universal Transverse Mercator UTM. Medium: Paper, flat copies only.

  • Total magnetic intensity data measures variations in the intensity of the Earth's magnetic filed caused by the contrasting content of rock-forming minerals in the Earth's crust. The data are collected on airborne geophysical surveys conducted by Commonwealth, State & NT Governments and the private sector.

  • Gravity data measure small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data are collected on geophysical surveys conducted by Commonwealth, State & NT Governments and the private sector.

  • The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium, uranium and thorium. The data are collected on airborne geophysical surveys conducted by Commonwealth, State & NT Governments and the private sector.

  • Product Specifications Coverage: Partial coverage, predominantly in northern Australia, along major transport routes, and other selected areas. About 1000 maps have been published to date. Currency: Ranges from 1968 to 2006. Coordinates: Geographical and UTM. Datum: AGD66, new edition WGS84; AHD. Projection: Universal Transverse Mercator UTM. Medium: Paper, flat copies only.

  • Australia's North West Margin (NWAM) is segmented into four discrete basins which have distinct rift and reactivation histories: Carnarvon, offshore Canning (Roebuck), Browse and Bonaparte. Bonaparte Basin incorporates Vulcan and Petrel sub-basins. The Bonaparte Basin stands out as an extensive sedimentary basin which has a geological history spanning almost the entire Phanerozoic, with up to 20 km of sediment accumulation in the centre. Browse Basin has considerably less thick sediment accumulation ? 12 km at maximum, which is still high for general hydrocarbon potential estimation. The structural architecture of the region is the product of a number of major tectonic events, including: ? Late Devonian northeast-southwest extension in the Petrel Sub-basin; ? Late Carboniferous northwest-southeast extension in the proto-Malita Graben, Browse Basin and proto-Vulcan Sub-basin; ? Late Triassic north-south compression; ? Early-Mid Jurassic development of major depocentres in the Exmouth, Barrow and Dampier sub-basins, and extension in the Browse Basin; ? Mid-Late Jurassic breakup in the Argo Abyssal Plain, onset of thermal sag in the Browse basin and extension in the Bonaparte Basin; ? Valanginian breakup in the Gascoyne and Cuvier abyssal plains, and onset of thermal sag in the Bonaparte Basin; and ? Late Miocene reactivation and flexural downwarp of the Timor Trough and Cartier Sub-basin Many of these events have involved processes of lower crustal extension and are strongly controlled by the pre-existing regional structural fabrics and basement character. Most reliable information on basement and deep crustal structure in the region comes from combined ocean-bottom seismograph (OBS) and deep reflection profiling along several regional transects (including Vulcan and Petrel transects in the Bonaparte Basin, and one transect in the Browse Basin). Average spacing between the OBSs of 30 km and shot spacing of 100 m with data recording to maximum offsets of 300 km enabled development of accurate crustal-scale seismic velocity models. Deep reflection data along the coincident profiles were recorded as part of Geoscience Australia?s regional grid of seismic lines. Consistent interpretation of several key horizons tied to petroleum exploration wells through the entire grid created the basis for co-interpretation of the OBS and deep reflection data supplemented by gravity field modelling.

  • Total magnetic intensity data measures variations in the intensity of the Earth's magnetic filed caused by the contrasting content of rock-forming minerals in the Earth's crust. The data are collected on airborne geophysical surveys conducted by Commonwealth, State & NT Governments and the private sector.