<div>The Abbot Point to Hydrographers Passage bathymetry survey was acquired for the Australian Hydrographic Office (AHO) onboard the RV Escape during the period 6 Oct 2020 – 16 Mar 2021. This was a contracted survey conducted for the Australian Hydrographic Office by iXblue Pty Ltd as part of the Hydroscheme Industry Partnership Program. The survey area encompases a section of Two-Way Route from Abbot Point through Hydrographers Passage QLD. Bathymetry data was acquired using a Kongsberg EM 2040, and processed using QPS QINSy. The dataset was then exported as a 30m resolution, 32 bit floating point GeoTIFF grid of the survey area.</div><div>This dataset is not to be used for navigational purposes.</div>

This service has been created specifically for display in the National Map and the chosen symbology may not suit other mapping applications. The Australian Topographic web map service is seamless national dataset coverage for the whole of Australia. These data are best suited to graphical applications. These data may vary greatly in quality depending on the method of capture and digitising specifications in place at the time of capture. The web map service portrays detailed graphic representation of features that appear on the Earth's surface. These features include the administration boundaries from the Geoscience Australia 250K Topographic Data, including state forest and reserves.

Legacy product - no abstract available

This map shows the boundary of the Maritime Security Zones for each port for the purpose of the Maritime Transport & Office Security Act 2003. 1 sheet (Colour) April 2010 Not for sale or public distribution Contact Manager LOSAMBA project, PMD

Legacy product - no abstract available

Legacy product - no abstract available

A pilot project conducted in October 1991, from Rig Seismic (AGSO Survey 104), utilising the continuous geochemical tracer [CGT] capability, showed that theanalyses of oceanic waters for light hydrocarbon content provides a useful method for characterising pollutants from various sources (BMR Research Newsletter, 16). The offshore Sydney component of Survey 104 was conducted between Botany Bay and North Head. Light hydrocarbon anomalies were detected from each of the three deepwater ocean outfalls operated by the Water Board. The results suggested that the molecular compositions of different hydrocarbon mixtures may be useful indicators of hydrocarbon 'sources' mixed together in the coastal zone. A reprint of the BMR Research Newsletter article of the pilot survey is reproduced in Figure 1.1. The usefulness of the CGT equipment, demonstrated during that pilot project, resultedin an additional survey (Survey 112), conducted on Rig Seismic during September/October 1992 (Heggie et al., 1992), which combined scientific staff from AGSO and the Water Board (Sydney). Scientific activities on Survey 112 included: (i)seafloor sampling, to gather environmental baseline information on the nutrient and contaminant (heavy metals and organochlorines) status of sediments, and also sedimentology of the nearshore region and, (ii) water column analyses, comprising approximately 500 line-km of CGT data (light hydrocarbons in seawater complemented with temperature, salinity, dissolved oxygen and pH) collected in the vicinity of the deepwater ocean outfalls. The purposes of this Record are to: (i) provide a description of the edited hydrographic (temperature and salinity), oxygen and pH data and, (ii) combine these data with some of the light hydrocarbon (DHD) data. Sediment and DHD data collected during Survey 112 are addressed in other AGSO Records (Heggie et al., 1993a; Heggie et al., I993b). A separate part of Survey 112, conducted with scientific staff from Sydney University, the NSW Geological Survey and the Ocean Sciences Institute, between Newcastle and Wollongong provides a regional context for thoseobservations focussed about Sydney. The preliminary results of that part of Survey 112 are included in Bickford and Heggie et al. (1993).

The Browse Basin underlies the outer shelf and upper slope of the central part of Australia'sNorth West Shelf, in water depths of 100-1000 m. Although the North West Shelf is generallyconsidered to be one of Australia's most heavily explored offshore regions, there aresignificant portions of it, such as the offshore Canning and Browse Basins, that remain under-explored. Relatively little is known of the primary structural architecture of the basin systemsof the North West Shelf, and the influence of that architecture on the occurrence ofhydrocarbons. The Browse Basin study (AGSO Project 121.28 - Basin development andhydrocarbon potential of the Browse Basin and adjacent margin) is part of a major AGSOregional research program over the north western Australian margin, and has the following main objectives: 1) Determine the regional structural framework of the Browse Basin and its relationship toadjacent features such as the Vulcan Sub-basin, Rowley Sub-basin, Scott Plateau andKimberley Block; 2) Define the broad deep-crustal structure of the region and develop a model explaining the tectonic, subsidence and thermal history of the basin in relation to the development of thecontinental margin and adjacent ocean basin (the Argo Abyssal Plain); 3) Assess the effects of deep structure and reactivation on the development of knownpetroleum accumulations. To address these objectives it is proposed that RV Rig Seismic be used to acquire about 3200km (up to a maximum of 3600 km depending on contingencies) of deep seismic and othergeophysical data along 11 lines tying 18 exploration wells in the Browse Basin/Scott Plateauregion. The survey will also tie into the 1990 Vulcan Sub-basin survey (98) to the northeast,and the forthcoming survey over the offshore Canning Basin to the southwest. In line with the Marine Geoscience and Petroleum Geology Program's (MGPGP's) most recentdeep seismic surveys over the North West Shelf, the Browse Basin survey will use a 4800 mstreamer, configured with 192 x 25 m active groups; data will be recorded with a 16 secondrecord length, and a 2 millisecond sample interval; the seismic source will be dual airgunarrays with a total capacity of 49 litres, and will be fired every 50 metres to give 48-fold CDPcoverage; and navigation will be by differential GPS. These parameters are the same as usedon two surveys over the northern Carnarvon Basin (SNOWS-1 and SNOWS-2) and threesurveys over the Bonaparte Basin - Timor Sea, and will also be used on the SNOWS-3 surveyover the offshore Canning Basin, following the Browse survey. Using these parametersAGSO has consistently recorded reflections down to 8-12 seconds two-way time (12-20 kmdepth), as well as obtaining good resolution in the upper 6 seconds of data, which is normallythe limit recorded by industry.

The effect of water and rock loading on seismic velocities and consequently on interpreted geometries is often underestimated in offshore studies. However, direct comparative analysis of interval velocity patterns between areas of significantly different water depth and thickness of rock overburden requires various pressure related changes in velocity to be accounted for. Presentation of velocity models as a function of pressure rather than two-way time, or depth, emerges as a possible solution. Accurate velocity model is essential for meaningful time-to-depth conversion of interpreted seismic horizons. Ideally, it should be based on integration of seismic velocities from well log measurements, refraction seismic surveys and from stacking of multi-channel marine reflection data. In some cases velocities derived from stacking of high quality long streamer marine reflection seismic data correlate reasonably with well measurements and velocities derived from refraction seismic studies, and provide clues to reasonable depth conversion and lithology interpretation.

APPEA extended abstract