The Study Of Remote Sensing Alteration Zoning Model Of Chinese Typical Porphyry Copper

The porphyry copper deposit is one of the important type of copper deposits of world. It's copper resources acconted for more than 50% of the world's copper. The porphyry copper deposit has a very good alteration zoning, which is used for study by remote sensing as an effective means. This paper studied the absorption mechanism of spectrum derived from the molecular vibrations or the electronic transition, which was the relationship of the mineral composition, the mineral formation temperature, the molecules key and the mineral spectral absorption, and summarized the alteration mineral absorption features of hydrothermal fluids in ASTER remote sensing data. Based on that, the Duolong porphyry copper ore concentratioin of Tibet of the alphine mountains, the Tuwu porphyry copper deposit of Xinjiang of the Gobi desert and the Dexing porphyry copper deposit of Jiangxi of the vegetation cover were studid as the typical deposits, to analyze and research their the mineralization geological background and mineral geological features, and the model of remote sensing alteration zoning of the porphyry copper deposits was built. In this model, the alteration zoning was formed due to the potassium hydrogen alteration halo of the magmatic hydrothermal fluids, which included potassium silicification, phyllic zone, mud zone and propylitic alteration zone from high-temperature to low-temperature of the magmatic hydrothermal fluids. It's results extraction using the model was consistent with the actual alteration zoning. The extraction method is porphyry copper alteration zoning information extraction techniques developed in this paper, which contained the data analysis, the information extraction and anomalies classification. The information extraction was the core of that, in which the main models were the ratio method, the slope method, the absorption depth method and the principal component analysis, based on the test and analysis of the rock and mineral spectrum.In this paper, the relationship of the element abundances and the spectral absorption characteristics of the vibration of molecular bonds and the electronic transitioin was studied as foundation, then geochemical sampling data were analyzed. The ASTER remote sensing spectral bands absorption features was associated with the copper content, on which the geochemical inversion using multiple regression analysis of the ratio, the slope index, the aborption depth index and the polynomial index of remote sensing based. The results were similar with 1:50000 measured geochemical results.The faults features of Duolong porphyry copper ore concentratioin of Tibet, the Tuwu porphyry copper deposit of Xinjiang and the Dexing porphyry copper deposit of Jiangxi were identified according to the radar data significant features on the fracture. The results were very good. The analysis of the structures of ore field using radar data had practical significance.Finally, the remote sensing model was built based on the metallogenic tectonic background, the characteristics of the magmatic roks and the surrounding rocks, structural characterisitics, the alteration features, the elements zoning features, the geochemistry and geophysical characteristics, the remote sensing alteration zoning model, the remote sensing geochemical characteristics, the structural features of radar data, the remote sensing images and lithological enhancement characteristics of the porphyry copper deposits, which was applied in mineral prospecting on Duolong ore concentratioin of Tibet, the target were preferred.