| Wall rock alteration is an important indication for exploitation, it is mean that the componential, ructural and tectonic change of the rock result from the temperature, hydrothermal and fizzwater.The ferriferous metallic minerals and alteration minerals which have OH-or CO32- . Most of endogenetic deposits have alteration phenomena of pyrite mineralization,sericitization,carbonatation etc, moreover because of hydrothermal ore-forming solution,, the region of alteration is bigger than that of deposit,this provide conditions for information extraction of alteration. Most of altered rocks have amount of Fe3+,OH-,CO32-. A mass test data of rocky spectrum proved that these ion have key reflecting or absorp bands from visible region to NIR, but the chemical constituent of rock-forming minerals (Si, Al, Mg, O) don't have the above spectral features, which constituted the physical foundation of alteration information extraction. Alteration information not only have spectral characteristics, but spatial characters. The spatial characteristics of alteration information means that the spatial distribution of alteration is controlled by structure, rock mass as well as other metallogenesis from geologic function aspect. The spatial characteristics of alteration are the basis of the interpretation of alteration information.Inner Mongolia is important metallogenetic area of Fe-Cu-Pb-Zn-Au etc. in the Western China. The geotectonic place is among syntaxial place between the fold systems of Baikalides and Daxinanlin Mountains, the ore-formation orientation, magmatic activity, deposition, mineralization of structural lineament is controlled by the deep fault. The intrusive rocks occured widely in the area, and chiefly distributing in Chagantaolegai, and the late period result of the Mesozoic including plagiogranite,granodiorite,monzonitic granite etc, the alkali granite,monzonitic granite, quartz diorite of early Yanshan period; granite porphyry, beschtauite of Yanshan late period; as well as dioritoid vein, quartz vein fragmentarily. The strata and irruptive rocks were not deteriorated, but hydrothermal fluid alteration is partly intense, which are essential signs of mineral prospecting.The content of Fe, Mn, Cu, Pb, Zn, Au, Ag, Mo etc. metal ones among more than twenty elements appearing in region of interest is higher and centralized partly. It has definite correlation with lithologic characteristic, structural feature of magmatic rock and lithologic characteristic of sedimentary rock through telement distribution of Fe, Mn, Pb, Zn, alunite etc. mineralized in connection with magmatic activity in early Yanshan period, and Cu, Mo, Ag, Au etc. accompanying with semivolcanic taxite intently. Their metallogenetic country rock and mineral ore indicate compatibility in space. More metal mineral occurrences were discovered in this area, mainly scarn magnetite containing Cu, Zn in the west of LongLinShan, porphyry Au,Mo mine in Changling, chrysargyrite in Longlinshan, Au, Mo mine in the north of this religion etc.. We also discovered three large-scale size geochemical anomaly, which wereâ…¡grade mining area in Longlin, Changlin, Halasheng.Through structural interpretation, lithologic interpretation combined with geological information, ETM images in region of interest from USA land satellite were processed by remote sensing image processing software platform. Firstly, the author carried out image mosaic, geometric correction, image enhancement, band-ratio analysis, and so on, enhancing and interpreting a lot of tectonic and concealed rock of this area. Secondly, the author studied alterative rocks and wall rocks' spectrum characters and differences within ETM bands, hereby, the model to enhance and extract the remote sensing information of mineralized alteration was established, and the remote sensing infornation of mineralized alteration were extracted by the"ETM mask+principal analysis+band-ratio analysis''. The author selected seven factors in favor of ore forming as the spatial information data resources. They are linear density anomaly of remote sensing, linear frequency anomaly of remote sensing, circular anomaly of remote sensing, geochemistry anomaly, geological anomaly and the known ore deposits (point). Finally, in the system of Map GIS 6.7, the author firstly integrated the geology map, remote sensing interpretation map, and mineralized alteration infomation map extracted from the remote sensing image, and analyzed synthetically the ore-forming geological background and the ore-controlling factors of this area, then utilizing GIS spatial analysis carries through synthetic analysis of multi-information made out the prospecting of ore-finding and confirmed five ore-finding forecast canes, which will be important instructing meaning to production and ore-finding in the future.In a word, iron-stained alteration information in this area is intensive and mainly distributes in the south,west part,northeast of the reseach area,southern area among them is the largest and the most intensive one, which shows lumpy distribution in the closely axial region of Manzhouli anticlinorium belt and is NE extension. Argillation alteration information is few,distributes mainly in the southwest and the center, which shows apparent NE banded distribution. According to the result of alteration information extraction,the characteristic of linear programming and circular structure, the distributional characteristics of rock mass etc compositive remote-sensed information establish three remote-sensed metallogenic prediction units, which consist in the south, west, northeast of the reseach area. Excavate the metallogenetic condition and metallogenetic characteristic of the prognostic units adequately, providing technical base for the investigation of mineral resources in the researching area.
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