No abstract available

Remotely sensed imagery has been used extensively in geomorphology since the availability of early Landsat data. Since that time, there has been a steady increase in the range of sensors offering data with increased spatial and spectral resolutions, from both government and commercial satellites. This has been augmented with an increase in the amount and range of airborne surveys carried out. Since 2000, digital elevation models have become widely available through the application of interferometric synthetic aperture radar, photogrammetry and laser altimetry (specifically LiDAR) with extensive uptake by geomorphologists. In addition, hyperspectral imaging, radiometrics and electromagentics have been made more accessible, whilst there has been increased use of close-range (<200 m) imaging techniques for very high resolution imaging. This paper reviews the primary sources for DEMs from satellite and airborne platforms, as well as briefly reviewing more traditional multi-spectral scanners, and radiometric and electromagnetic systems. Examples of the applications of these techniques are summarised and presented within the context of landscape pattern recognition and modelling. Finally, the wider issues of access to geographic information and data distribution are discussed.

single page item on Australian stratigraphy issues. This column discusses ongoing co-operation between the State and Territory Surveys; highlights of a trip to the Northern Territory and changes to GA web pages Journal ISSN 0312 4711

Weather conditions during the survey were generally very good with only a few days of seas of about two metres. Technically and scientifically, the balance of the program changed when the seismic (and magnetic) program was reduced to one third of the expected kilometres because of the failure of the compressor. Fortunately, two of four critical lines running WNW-ESE were acquired (Table 1). Data acquisition rates (average of 200 km/day) were tolerable and seismic data quality was good. A whale watch was kept in accord with the requirements of the Department of the Environment and Heritage, but no whales were seen. The dredging program was increased to take advantage of the reduced seismic program, and most Mellish Rise sites were located either on the two new seismic lines or on pre-existing BMR continental margin survey seismic lines. A number of sites on the Kenn Plateau made use of seismic data from last year's Southern Surveyor Cruise SS5/04. The need to use BMR seismic lines moved the dredging balance to the western half of the area. Of the 44 dredges attempted, 37 (85 %) produced valuable results (Table 3). The swath-mapper was invaluable in designing dredge plans. The coring program of 5 cores (Table 2) produced three moderately successful cores, but was disappointing overall. The two seismic lines extend right across the Mellish Rise and reveal how the area has been affected by tension but not compression, with high blocks 50-100 km across separated by heavily sedimented graben of similar width. Satellite bathymetry and gravity maps, and the total seismic data set show that structural trends bounding the blocks are NW-SE, N-S and NE-SW. Numerous smaller horsts rise above the broad highs. Dredges from the Coriolis Ridge and the Selfridge Rise, both on the northern Kenn Plateau, are dominated by silicic volcanics of continental origin, siliciclastic sediments, and shallow marine carbonates (some reefal). Basaltic volcanics are rare. The continental volcanics may be rift-related (Upper Cretaceous to early Eocene). The calcarenites may be Eocene and Oligocene in age. Dredges from the generally deeper water (thinner crust) Mellish Rise are different, being dominated by basaltic volcanics and hyaloclastites, although silicic volcanics, siliciclastic sediments, and shallow marine carbonates (some reefal) occur. Two phases of volcanism, rift related (Upper Cretaceous to early Eocene) and hotspot related (late Eocene-Oligocene) may well be present. Three dredges from a southern protrusion of the Louisiade Plateau, which is not necessarily genetically related to that plateau, contain basaltic volcanics and hyaloclastites, silicic volcanics, siliciclastic rocks, and shallow marine carbonates in an assemblage like that of the Mellish Rise. Until exhaustive laboratory studies of the rocks are carried out, the above generalisations remain speculative. In the end, the volcanics could be related to any of four known periods of volcanism: ? The Late Jurassic (145-135 Ma) subduction-related volcanism of the Graham?s Creek Formation in the Maryborough Basin: tuffs, agglomerates and volcanic breccias, overlain by trachyte and rhyolite flows, overlain by basaltic andesite and dacite. ? The Early Cretaceous (125-115 Ma) explosive rift-related volcanism of the Whitsunday and Cumberland Islands: dacite, rhyolite, and andesitic ignimbrite. ? The assumed Late Cretaceous to Paleocene rift-related volcanism of the Marion Plateau (drilled in ODP Leg 194): altered basalt flows and volcaniclastic breccias and conglomerate. ? The Late Eocene to Early Oligocene hotspot volcanism of the Tasmantid chain: basalts and hyaloclastites.

Defining a neotectonic fault in the intraplate context is relatively straightforward - the fault must have hosted displacement in the current crusta stress regime. Defining an active fault is far more problematic, depending upon the recurrence of the fault (and nearby faults) and the return period being considered for hazard purposes. This article discusses the term "active" and provides some examples of faults from eastern Australia for emphasis.

This paper is an introduction to the two AJEM Special Issues on risk assessment. The role of risk assessment in emergency management in Australia is firmly established and much progress has been made in utilising risk modelling tools and supporting data to develop new information on risk for some hazards. Significant further work is required to reach an understanding of all hazards risks nationally.

Part-page article on matters relating to Australian stratigraphy. This column discusses what constitutes a publication for the purpose of establishing and formalising stratigrphic units. ISSN: 0312 4711

Overview of the Deep Crustal Seismic surveys conducted by Geoscience Australia and funded through the Onshore Energy Security Program since it's commencement in 2006 to September 2009.

We measured the light absorption properties of two naturally occurring Australian hydrocarbon oils, a Gippsland light crude oil and a North West Shelf light condensate. Using these results in conjunction with estimated sensor environmental noise thresholds, the theoretical minimum limit of detectability of each oil type (as a function of oil thickness) was calculated for both the hyperspectral HYMAP and multispectral Quickbird sensors. The Gippsland crude oil is discernable at layer thickness of 20 micro metres or more in the Quickbird green channel. The HYMAP sensor was found to be theoretically capable of detecting a layer of Gippsland crude oil with a thickness of 10 micro metres in approximately six sensor channels. By contrast, the North West Shelf light condensate was not able to be detected by either sensor for any thickness up to 200 icro metres. Optical remote sensing is therefore not applicable for detecting diagnostic absorption features associated with this light condensate oil type, which is considered representative for the prospective Australian Northwest Shelf area. We conclude that oil type is critical to the applicability of optical remote sensing for natural oil slick detection and identification. We recommend that a sensor- and oil-specific sensitivity study should be conducted prior to applying optical remote sensors for oil exploration. The oil optical properties were obtained using two different laboratory methods, a reflectance-based approach and transmittance-based approach. The reflectance-based approach was relatively complex to implement, but was chosen in order to replicate as closely as possible real world remote sensing measurement conditions of an oil film on water. The transmittance-based approach, based upon standard laboratory spectrophotometric measurements was found to generate results in good agreement with the reflectance-based approach. Therefore, for future oil- and sensor-specific sensitivity studies, we recommend the relatively accessible transmittance-based approach, which is detailed in this paper.

The Australian Government policy is to ensure that uranium mining, milling and rehabilitation is based on world best practice standards. A best practice guide for in situ recovery (ISR) uranium mining has been developed to communicate the Australian Government's expectations with a view to achieving greater certainty that ISR mining projects meet Australian Government policy and consistency in the assessment of ISR mine proposals within multiple government regulatory processes. The guide focuses on the main perceived risks; impacts on groundwaters, disposal of mining residues, and radiation protection. World best practice does not amount to a universal template for ISR mining because the characteristics of individual ore bodies determine the best practice