image processing
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If colour TMI map is purchased with greyscale TMI map the price is $269.80 (inc GST) for both
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This two year collaborative project was established in July 2006 with the overall aim of developing, validating, evaluating and delivering a suite of publicly available, pre-competitive mineral mapping products from airborne HyMap hyperspectral imagery and satellite multispectral ASTER imagery. Moreover, it was important to establish whether these mineral maps would complement other precompetitive geological and geophysical data and provide valuable new information regards enhanced mineral exploration for industry. A mineral systems approach was used to appreciate the value of these mineral maps for exploration. That is, unlocking the value from these mineral maps is not simply by looking for the red bulls-eyes. Instead, mineral products need to be selected on the basis of critical parameters, such as what minerals are expected to develop as fluids migrate from source rocks to depositional sites and then into outflow zones with each associated with different physicochemical conditions (e.g. metasomatic metal budget, nature of the fluids, water-rock ratios, lithostatic pressure, pore fluid pressure, REDOX, pH, and temperature). One of the other key messages is to be able to recognise mineral chemical gradients as well as anomalous cross-cutting effects. These principles were tested using a number of case histories including, (1) the Starra iron oxide Cu-Au deposit; (2) the Mount Isa Pb-Zn-Ag and Cu deposits; and (3) Century Zn, all within the Mount Isa Block. These showed that the interpreted mineral alteration footprints of these mineral systems can be traced 10-15 km away from the metal deposition sites. In summary this project has shown that it is possible to generate accurate, large area mineral maps that provide new information about mineral system footprints not seen in other precompetitive geoscience data and that the vision of a mineral map of Australia is achievable and valuable.
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The International Forest Carbon Initiative, IFCI, is part of Australia's contribution to international efforts on reducing carbon emissions from deforestation and forest degradation. It focuses on technology transfer to developing countries by assisting them to implement national carbon accounting schemes modelled on that established by the Department of Climate Change and Energy Efficiency. Key inputs to those accounting schemes are mosaics of the best available satellite scenes in a given year. Collections of these mosaics, spanning periods of at least a decade, are used to determine changes to the extent and type of forest cover. Those characterisations are used to determine net forest carbon flux, which is a significant component of overall carbon flows in tropical countries. In support of these activities, Geoscience Australia manages a project to obtain, process, archive and distribute large volumes of satellite data, initially with a focus on Indonesia and other parts of Asia. Three key changes from 'business as usual' activities were required to process and manage, on a large scale, a satellite data time-series to support the International Forest Carbon Initiative. First, at Geoscience Australia, a new facility known as the Earth Observation Data Store is being developed. Secondly, innovative techniques such as the use of USB Flash Drives for data distribution and of DVDs for quick look catalogue distribution have proved beneficial for the participating agencies in developing countries, as well as for data transfers from regional satellite archives. Thirdly, much of the data, especially the Landsat satellite imagery, has for the first time been made available to the users with minimal restrictions, via the employment of open content licensing known as Creative Commons.
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Pixel Quality Assessment describes the results of a number of quality tests which are used to determine the quality of a Landsat image product in terms of, pixel saturation, pixel contiguity between spectral bands, whether the pixel is over land or sea, cloud contamination, cloud shadow and topographic shadow. Pixel Quality is used to filter an input Landsat image for downstream processing in a production workflow. It has general applicability to a number of image processing scenarios.
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Legacy product - no abstract available
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Legacy product - no abstract available
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Legacy product - no abstract available
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Exploration advances: New developments in spectral remote sensing in the Mount Isa region, Australia
Advanced spectral remote sensing can be a valuable tool for explorers in both green-fields and brown-fields exploration. Using highly-calibrated spectral data and processing techniques, new perspectives can be gained in mapping and characterising materials at the surface. Surface expression of underlying materials, such as ore-deposits, can also be mapped and characterised using these methods. Mineral maps and products made from spectral datasets that can be integrated with other datasets provide a ready-to-use tool that aids explorers in identifying and mapping unconsolidated regolith material and underlying bedrock. In the Mount Isa region, bedrock signatures have been discovered in areas recorded as extensive cover sediments where no bedrock had been previously mapped. This means that in addition to being able to make mineral classifications that characterise transported materials, it is also possible to find new windows of basement geology in areas previously mapped as cover. This has useful applications for mapping geomorphic processes in that it helps to understand mineral dispersion pathways and target surface sampling for mineral exploration. The Predictive Mineral Discovery Cooperative Research Centre (pmd*CRC) developed a comprehensive spectral geology study in conjunction with the Queensland State Government's Smart Exploration Program as part of a joint venture to collect and process new hyperspectral data in Queensland, and to calibrate an existing Advanced Spaceborne Thermal Emission and Reflective Radiometer (ASTER) satellite mosaic, of some ~150 ASTER scenes. This work demonstrated that a considerable amount of geochemical information about hydrothermal deposit "footprints" and alteration chemistry can be acquired by analysing spectral ground response, particularly in the short-wave infra-red where a great deal of mineralogical information is available. Materials which can be mapped include clays and magnesium/iron/aluminium oxyhydroxides, with specific information being obtainable (using higher resolution airborne methods such as HyMap) on mineral composition, abundance and physicochemistries (including crystallinity) for minerals such as kaolinite which can be used as a surrogate for identifying transported vs. in situ material. High resolution mineral maps enable the recognition of various types of hydrothermal alteration patterns and the localisation of fluid pathways, including geochemically discrete alteration shells in IOCG type deposits which correspond to distinct mineral distributions. Potassic alteration in mafic rocks was detected using a combination of MgOH and Fe2+-mineral maps combined with white mica composition and abundance products. MgOH and Fe2+-mineral products were also used to distinguish amphibolites, which form the host rocks for some of the Fe oxide Cu-Au deposits area, from other various mafic rocks.
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The Australian Geological Survey Organisation (AGSO) presents its solutions to mapping, GIS and image processing on the Internet. Software used is based on commercial and open source products. A distributed web mapping system is demonstrated, and concepts of distributed web mapping discussed. A model and prototype system for online delivery of satellite image data is presented. AGSO has been providing Internet access to spatial data since 1996. AGSO is the main repository for national geoscientific data, and services a wide range of clients across industry, government and the general public. Data provided range from point data, such as site descriptions and scientific analysis of samples, to line polygon and grid data, such as geological and geophysical surveys and associated maps. AGSO currently holds 500 MB of GIS data and a similar amount of image data on its web site, these data are expected to expand to a number of terabytes over the next few years. A primary role of AGSO is to provide its data to clients and stakeholders in as efficient a way as possible, hence its choice of Internet delivery. The major obstacle for supplying data of large volume over the Internet is bandwidth. Many AGSO clients are in remote locations with low bandwidth connections to the Internet. Possible solutions to this problem are presented. Examples of AGSO web tools are available at http://www.agso.gov.au/map/
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Londonderry - Drysdale Potassium (red), Thorium (green), Uranium (blue) colour composite