Soil mapping at the local- (paddock), to continental-scale, may be improved through remote hyperspectral imaging of surface mineralogy. This opportunity is demonstrated for the semiarid Tick Hill test site (20 km2) near Mount Isa in western Queensland, which is part of a larger Queensland government initiative involving the public delivery of 25,000 km2 of processed airborne hyperspectral mineral maps at 4.5 m pixel resolution to the mineral exploration industry. Some of the "soil" mineral maps for the Tick Hill area include the abundances and/or physicochemistries (chemical composition and crystal disorder) of dioctahedral clays (kaolin, illite-muscovite and Al smectite, both montmorillonite and beidellite), ferric/ferrous minerals (hematite/goethite, Fe2+-bearing silicates/carbonates) and hydrated silica (opal) as well as "soil" water (bound and unbound) and green and dry (cellulose/lignin) vegetation. Validation of these hyperspectral mineral products is based on field sampling and laboratory analyses (spectral reflectance, X-ray diffraction, scanning electron microscope and electron backscatter). The mineral maps show more detailed information regards the surface composition compared with the published soil and geology (1:100,000 scale) maps and airborne radiometric imagery (collected at 200 m line spacing). This mineral information can be used to improve the published mapping but also has the potential to provide quantitative information suitable for soil modeling/monitoring.

The Landsat series of satellites commenced acquiring remotely sensed data with the launch of Landsat 1 in 1972. The Landsat satellites travel at an altitude of 705 kilometres and provide coverage of the entire globe every 16 days. The Multispectral Scanner (MSS) sensor has been the primary Earth-observing instrument. MSS images in four spectral bands (called Bands 4-7 on LS1,2&3 and 1-4 on LS 4&5) covering the visible and near infrared regions of the electromagnetic spectrum. The MSS ground swath is 185 kilometres wide, with a nominal 80 metre pixel resolution. The archive of ACRES MSS data dates from 1979 onwards. ACRES MSS archive contains data from the following Landsat satellites: Landsat 2 commenced November 1979, ceased Feb 1982 Landsat 3 commenced November 1979 ceased August 1982 Landsat 4 commenced August 1982, ceased May 1984 Landsat 5 commenced 9 April 1984, ceased November 1997 - Band 4 (original band 7) data poor quality from 29 April 1994 - Band 4 (original band 7)switched off permanently 20 August 1995 Note that MSS data from Landsat 3 & 4 is of poor quality and requirements for this data need to be discussed with ACRES prior to purchase.

The Landsat series of satellites commenced acquiring remotely sensed data with the launch of Landsat 1 in 1972. Landsat satellites travel at an altitude of 705 kilometres and provide coverage of the entire globe every 16 days. Landsat 7, launched on 15 April 1999, carries the Enhanced Thematic Mapper Plus (ETM+). As the name suggests, the ETM+ sensor is similar to the TM sensor but has some added features. It provides imagery in the same seven spectral bands as the TM sensor with 30 metre resolution, but has an added panchromatic band with 15 metre pixel resolution. ETM+ also has an enhanced thermal band with a 60 metre resolution. Its ground swath is 185 kilometres. A full scene is approximately 184 kilometres by 172 kilometres. The archive of ACRES products includes ETM+ data from 6 July 1999 onwards.

The JERS-1 satellite was developed by the National Space Development Agency of Japan (NASDA). JERS-1 was launched in February 1992 and operated until 11 October 1998. The satellite traveled at an altitude of 568 kilometres and provided coverage of the entire globe every 44 days. The L-band, Synthetic Appeture Radar (SAR) sensor was the primary Earth-observing instrument. The SAR is an active microwave sensor capable of imaging earth resource targets regardless of time of day, cloud, haze or smoke cover of an area. The instrument is classified "active" as it emits the energy necessary to image the earth's surface. In contrast, "passive" or "optical" sensors rely on the sun's reflected energy to image the earth. The SAR ground swath is 75 kilometres wide, with a nominal 18 metre pixel resolution. The sensor has HH polarisation. ACRES JERS SAR acquisition commenced in September 1993 and ended in October 1998.

Two ERS satellites have been developed by the European Space Agency (ESA). ERS-1 was launched on 17 July 1991 and ERS-2 on 20 April 1995. Both ERS satellites travel at an altitude of 785 kilometres and provide coverage of the entire globe every 35 days. The C-band, Synthetic Appeture Radar (SAR) sensor has been the primary Earth-observing instrument. The SAR is an active microwave sensor capable of imaging earth resource targets regardless of time of day, cloud, haze or smoke cover of an area. The instrument is classified "active" as it emits the energy necessary to image the earth's surface. In contrast, "passive" or "optical" sensors rely on the sun's reflected energy to image the earth. The SAR ground swath is 102.5 kilometres wide, with a nominal 30 metre pixel resolution. The sensor has VV polarisation. ACRES ERS-1 archive includes data acquired from September 1991 to March 2000, while ACRES ERS-2 acquisitions started in November 1995 and continues to present.

The regional assessment of hydrocarbon seepage is built around a combination of Radarsat and ERS Synthetic Aperture Radar (SAR) data, acquired during 1998 and 1999, as part of a collaborative project between AGSO - Geoscience Australia, Nigel Press & Associates, Radarsat International and AUSLIG (specifically the Australian Centre for Remote Sensing). In total, 55 Radarsat Wide 1 Beam Mode scenes and 1 ERS scene from the Great Australian Bight (GAB) region were analysed. The data were integrated with regional geological information, and other hydrocarbon migration/seepage indicators such as reprocessed and reinterpreted legacy Airborne Laser Fluorosensor (ALF) data, to provide an assessment of the possible charge characteristics of the region. The results of the study suggest that active, though areally restricted, liquid hydrocarbon seepage is occurring within the Bight Basin. The majority of seepage slicks occur along the outer margin of the major depocentre, the Ceduna Sub-basin, in areas where significant Late Tertiary to Recent faulting extends to the seafloor. Very little evidence of seepage was observed on the SAR data above the main depocentre, which is an area of minimal Late Tertiary to Recent faulting. Reprocessed ALF data reveal three main areas with relatively dense fluors. Although they are not directly coincident with locations of seepage interpreted from SAR data, their distribution support the pattern of preferred leakage along the basin margins. Integration of regional geological models with the results of this study suggests that structural features related to active tectonism have focused laterally migrating hydrocarbons to produce active seepage at specific locations in the basin. Where these features are absent, seepage may be passive and/or be governed by long distance migration to points of seal failure. Together with oil and gas shows in exploration wells, observations from this study provide further evidence that liquid hydrocarbons have been generated in the Great Australian Bight.

These AUSLIG/ACRES datasets represent the coverage of LANDSAT5 TM scenes, The ERS paths, SPOT paths and the locations of RADARSAT scenes over the Australian region. The LANDSAT5 TM dataset is attributed with the path and row numbers of scenes. This dataset can be used in conjunction with the AGSO REMOS database to locate satellite imagery AGSO holds. The RADARSAT dataset represents all the radarsat (SAR) scenes AGSO (PMD) has purchased and have stored in-house. SAR stands for Synthetic Aperature Radar. RADARSAT is a Canadian satellite and scenes are from a company called RADARSAT International (RSI). AGSO (PMD) updates its holdings of these satellite scenes on a 6 monthly basis. Almost all scenes have been interpreted by AGSO and external contractors. Please speak to Mark Webster for more information on this.

Continent-scale digital maps of mineral information of the Earth's land surface are now achievable using geoscience-tuned remote sensing systems. Multispectral ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) data and the derived mineral information provide the opportunity for characterization of geological and soil processes including the nature of the regolith (weathered) cover and alteration footprints of hydrothermal ore deposits [1,2]. This paper describes work from the Western Australian (WA) Centre of Excellence for 3D Mineral Mapping, which is part of CSIRO's Minerals Down Under Flagship and supported by Geoscience Australia and other Australian geosurveys, to generate a series of ASTER mineral group maps (both content and composition) for the whole Australian continent at a 30 m pixel resolution.. The input ASTER L1B radiance-at-sensor data were provided by ERSDAC (Japan), NASA and the USGS. These data were corrected for instrument, illumination, atmospheric and geometric effects. About 4000 ASTER scenes from an archive of >30,000 scenes were selected to generate the continent-scale ASTER map and Hyperion scenes were used for reduction and validation of the cross-calibrated ASTER mosaic to reflectance. Band ratios [2] were applied as base algorithms and masked to remove complicating effects, such as green vegetation, clouds and deep shadow. Types of generated geoscience products include (1) mineral group content maps based on continuum-band depths (e.g. Al-OH group content mapping Al-OH clays like muscovite, kaolinite and montmorillonite) and (2) mineral group composition maps (e.g. Al-OH group composition ranging from Si-rich white mica through to well ordered kaolinite) based on ratios but masked using the relevant content products.

Includes copy of AGSO Record 1997/20

A multi-agency collaboration between Australian government partners has been working towards making continent-scale, public, web-accessible and GIS-compatible ASTER geoscience maps. CSIRO along with Geoscience Australia and several state government agencies, (including GSWA, GSQ, DMITRE and NTGS), have developed methodology and produced 15 geoscientific products, with applications for mineral mapping and exploration, soil-mapping, environment and agricultural sectors. This work represents the largest ASTER mosaic of this type in the world and sets a new benchmark for state-to-continent scale spectral remote sensing. The project is supported both nationally and internationally by the ASTER Science Team, ERSDAC, NASA and the USGS. Outcomes include the formation of a platform for establishing national standards; geoscience product nomenclature; processing methods; accuracy assessments; and traceable documentation. Detailed product notes outline these standards and provide significant knowledge transfer for existing and new users of this type of data. Hyperion satellite hyperspectral imagery has been critical for calibration and validation of the processed ASTER data, reduction to 'surface' reflectance using independent validation data such as Hyperion, and calculating statistics to generate regression coefficients, reduces errors in the ASTER instrument and increases reliability and corroboration of spectral responses.