Henson P.A., Gibson G.M., Debenham S., Kalinowski A., Barlow M. & McIntyre A. 2004. 3D structural model for the northern Leichhardt River Fault Trough and adjacent Lawn Hill Platform, Mt Isa. In: Barnicoat A.C. & Korsch R.J. eds. Predictive Mineral Discovery Cooperative Research Centre: Extended Abstracts from the June 2004 Conference. Geoscience Australia, Record 2004/9, 91-94.

We report the discovery of three submerged, living patch coral reefs covering 80 km2 in the southern Gulf of Carpentaria, Australia, an area previously thought not to contain coral bioherms. The patch reefs have their upper surfaces at a mean water depth of 28.6±0.5 m, and were consequently not detected by satellites or aerial photographs. The reefs were only recognised in our survey using multibeam swath sonar supplemented with seabed sampling and under water video. Their existence points to an earlier, late Quaternary phase of framework reef growth, probably under cooler climate and lower sea level conditions than today. Submerged reefs with surfaces between 20 and 30 m water depth occur in other regions of the Earth and existing bathymetry indicates they could be widespread in the Gulf. Many tropical regions that today do not support patch or barrier reefs for reasons similar to the modern Gulf, may have done so in the past, when environmental conditions were more suitable. Submerged reefs may provide an important refuge for corals during the next few decades when near-surface reefs are threatened by widespread coral bleaching due to warmer global sea surface temperatures.

This dataset contains point, line and polygon water supply, waste water, power, fuel, gas and telecommunications data for the Cocos (Keeling) Islands. Coverage is of Home and West Islands.

Product no longer exists, please refer to GeoCat #30413 for the data

Product no longer exists, please refer to GeoCat #30413 for the data

Product no longer exists, please refer to GeoCat #30413 for the data

Recent field observations have identified the widespread occurrence of fluid seepage through the eastern Mediterranean Sea floor in association with mud volcanism or along deep faults. Gas hydrates and methane seeps are frequently found in cold seep areas and were anticipated targets of the MEDINAUT/MEDINETH initiatives. The study presented herein has utilized a multi-disciplinary approach incorporating observations and sampling of visually selected sites by the manned submersible Nautile and by ship-based sediment coring and geophysical surveys. The study focuses on the biogeochemical and ecological processes and conditions related to methane seepage, especially the anaerobic oxidation of methane (AOM), associated with ascending fluids on Kazan mud volcano in the eastern Mediterranean. Sampling of adjacent box cores for studies on the microbiology, biomarkers, pore water and solid phase geochemistry allowed us to integrate different biogeochemical data within a spatially highly heterogeneous system. Geophysical results clearly indicate the spatial heterogeneity of mud volcano environments. Results from pore water geochemistry and modeling efforts indicate that the rate of AOM is 6 mol m-2 year-1, which is lower than at active seep sites associated with conditions of focused flow, but greater than diffusion-dominated sites. Furthermore, under the non-focused flow conditions at Kazan mud volcano advective flow velocities are of the order of a few centimeters per year and gas hydrate formation is predicted to occur at a sediment depth of about 2 m and below. The methane flux through these sediments supports a large and diverse community of micro- and macrobiota, as demonstrated by carbon isotopic measurements on bulk organic matter, authigenic carbonates, specific biomarker compounds, and macrofaunal tissues...

Basin architecture and fault geometries in the Mount Isa Western Succession: implications for mineral exploration. North Queensland Exploration and Mining 2004; extended abstracts. Australian Institute of Geoscientists Bulletin 40, p.121-22.

Australia is not on the edge of a tectonic plate so why do we have earthquakes? The Indian-Australian plate is being pushed north and is colliding with the Eurasian, Philippine and Pacific plates. This causes stresses to build up in the interior of the plate which is released during earthquakes.

Kakadu_2004_ortho_DEM