1. Content Overview
Remote sensing refers to non-contact, long-distance detection technology. This definition does not distinguish remote sensing from airborne geophysical prospecting. Generally speaking, remote sensing refers to the technology of detecting and identifying electromagnetic waves, visible light, and infrared targets reflected or radiated by the target from a long distance. Simply put, geological remote sensing is a method that uses the spectral response of detection objects to conduct geological research. Australian geologists refer to geological remote sensing as spectral geology, which may be a more accurate name. However, it is easily confused with general rock or mineral spectroscopy. The latter uses equipment such as infrared spectrometer or Raman spectrometer to measure its spectral characteristics. It generally belongs to the research scope of petrology or mineralogy and is very different from the usual remote sensing geology. the difference.
Spectral geology is to measure and analyze a certain range of the electromagnetic spectrum in order to identify the physically important and relatively clear spectral characteristics of different rock types, surface materials, minerals and alteration markers. Spectral geology is mainly based on the principle of interaction between electromagnetic radiation (visible light and infrared light) and matter, using a series of spectral detection technologies to measure, map and monitor mineral systems or environmental systems.
The goals of CSIRO spectral detection research: ① Provide a method to generate a new generation of regolith (supercrust rock), geological and altered mineral distribution maps; ② Increase the accuracy of drilling through online mineral cataloging Added value; ③ Make automatic mapping of mine conditions possible; ④ Improve the level of environmental management.
CSIRO’s research on spectral detection technology focuses on four main areas of resources: ① New generation mineral mapping, including: the development of algorithms and software for interpreting remote sensing hyperspectral and multispectral data to Carry out mineral and geological mapping; study the spectral characteristics of fresh and weathered mineral systems, especially the performance of gold, base metals, light metals, nickel and iron ores in the VNIR-SWIR wavelength range; analyze the generated mineral maps and geological products Conduct assessment and validation; build geological, regolith and alteration case studies. ② New generation of environmental mapping, including: developing algorithms and software to measure environmental parameters based on remote sensing data; studying the characteristics of key environmental indicators (especially dust and acid drainage), as well as the ecology of the light metal, iron ore and coal mining industries Metrics such as spectral (VNIR-SWIR-TIR wavelength), spatial (bidirectional reflectance distribution function) and temporal (natural vegetation and soil dynamics); evaluate and validate the mineral maps and environmental products obtained. ③HyloggignTM. The HyloggignTM system utilizes visible and infrared spectrometers, high-spectral rate imagers and automatic core trays to operate and catalog, and can complete more than 1000 m per day. Current research includes the development of commercially available automated spectral cataloging hardware and software systems for diamond drill cores, drill bit fragments and blasthole powders; and the development of thermal infrared cataloging capabilities for silicate mapping and demonstration in Western Australia. ④Ore smelting technology. CSIRO's ore smelting technology research includes: developing a mine planning system based on mineralogy; and developing a spectral phase mapper for the nickel laterite and iron ore mining industries.
2. Application scope and application examples
In 2007, Australian scientists built one of the largest ASTER mosaics in the world so far, covering Mount Isa in northwest Queensland. area. This mosaic contains more than 15 geoscience products used to help surveyors examine hydrothermal systems and their surface conditions. This work continues, with collaborators from the CSIRO State Geological Survey extending and improving the technology to improve understanding of alteration and regolith in the region. Geoscience Australia, together with CSIRO and its three-dimensional mineral mapping center, has released a large number of ASTER mosaic maps and related value-added geoscience products. The total number of ASTER mosaic maps in the Gawler-Curnamona area of ??South Australia exceeds 100. Data for these projects can be obtained from the CSIRO FTP website.
Work is currently underway on a mosaic around Alice Springs in the Northern Territory.
In addition, a collaborative project is underway with CSIRO, the Earth Remote Sensing Data Analysis Center (ERSDAC), NASA's Jet Propulsion Laboratory (JPL) and colleagues in state and industry to develop an ASTER mosaic of the entire Australia and related geoscience products. Australia has also conducted pilot experimental research on the use of MODIS night-time thermal imaging for geothermal exploration, and hopes to continue to carry out application research based on other night-time and thermal imaging in Australia.
Australia uses spectral geology for detailed mineral mapping and regolith mapping, and analyzes ore bodies and their surface characteristics through some means (such as HyMapTM and ASTER). It also uses spectroscopy to pinpoint the microstructure associated with different fluid phases through equipment such as the laser RAMAN microprobe, the Portable Infrared Mineral Analyzer (PIMA), and CSIRO’s Automated Hole Core and Debris Logger (HyLoggerTM). Subtle changes in minerals. Geoscience Australia's project has also obtained a series of satellite and remote sensing images and value-added spectral products from ASTER, EO-1 Hyperion and ALI.
As part of its project to detect traces of hydrocarbons located on the continental shelf and offshore waters, Geoscience Australia has been conducting a project to evaluate the effectiveness of using HyMapTM hyperspectral imagery to detect the extent of offshore oil spills on Timor Island. sex. This work is carried out in areas with known natural hydrocarbon leaks and production areas with man-made oil patches.
Geoscience Australia is a provider, storer and user of many kinds of spectral data and related products. It provides MODIS, ASTER, Landsat and other images to users around the world.
3. Data sources
Spectral Geology.es/Mineral?Resources/ Minerals?Exploration/Spectral?sensing?technologies.aspx.1 June 2005 | Updated 14 October 2011