Study On Remote Sensing Prospecting Information Extraction Of Copper Polymetallic Mineral In Deqin-Muli Area, San Jiang Region, Southwest China

Metallogenic Belts of San-jiang Region，Southwest China is important part of Tethys-Himalayan giant metallogenic domain. Metallogenic belt which existed strong tectonic-magmatic-Fluid Activities has experienced a late Paleozoic-Mesozoic tectonic evolution ofTethys， then gone through the Cenozoic continental collision orogeny superimposedconversion. The metallogenic belt has excellent metallogenic conditions and huge resourcepotential. The paper selects Denqin-Muli as study area， using remote sensing techniques toextract mineralization information. As the high vegetation cover in the study area，effectivelyextracting mineralization information becomes difficult problems. The paper summarizesmineral geological features in the study area by analyzing the achievements of formerresearches and research results. The Paper collectes geology，minerals，vegetation，soil andvegetation spectral information in the study area by conducting filed geological investigation.Paper extracts prospecting information by using remote sensing techniques，then delimitsprospecting areas by analyzing the distribution characteristics of deposit combined withgeological data. The main contents and the main research results obtained as follows：（1）The paper gathers multispectral， hyperspectral and radar remote sensing data foreffective integration by using the methods of digital image processing. The study area islocated in the midland of southwest of "sanjiang"，where it is medium to high vegetationcoverage. This study choses optical and radar data，integrated the advantages of two kinds ofdata for the extraction of remote sensing mineralized weak information research. Radiationcorrection，geometric correction，mosaicing and fusion，are applied to preprocessing opticalremote sensing data. And focusing，multilooking，speckle filtering，geocoding and radiationcalibration are applied to preprocessing radar data. Through these operations，this paperrealizes the integration of the radar data and optical data，and summarizes these integrationmethods and techniques suitable for remote sensing mineralized information extraction ofmulti-source remote sensing data.（2）The paper interprets lineament and circular structure by using remote sensingtechnology. This study combines the advantages of optical and radar data to interpret structure. This paper uses the OLI remote sensing data to do regional macro structuralinterpretation，and through some image enhancement，such as the color compositing andconvolution filtering of OLI remote sensing data，texture and linear information can behighlighted. By utilizing high-pass filtering，laplacian filtering and directional filtering，partof convolution filtering，linear structure enhancement effect is obvious. Synthetic apertureradar data that fuses together with multi-spectral data，or processes with polarizationsynthesis method， can effectively strengthen geological structure information.Multi-polarization data using2HV，HH+VV，HH-VV as RGB channels to map to pseudocolor composite image，which has the advantages of moderate color contrast and effectiveenhancement of image texture feature， can well reflect the structural information.Single-polarization data fusing together with OLI multispectral remote sensing data，composites the information of colorful multispectral image data and abundant texture featureof SAR image data，and effectively strengthen structure information.（3）The paper summarizes lineament and circular structure distribution characteristicsby using the quantitative analysis method to analyze distribution of lineament and circularstructure in the study area. From the rose diagram analysis，it is concluded that the lineamentdirectionality is strong，the north-west to the lineament is developed，minor developmentaldirections are south-north direction and north-east. In the study area，lineament partitioncharacteristics is obvious，local differences advantage is apparent. West of jinsha river regionin the study area mainly developed nearly NS-trending lineament，and in the eastern region，structure mainly appears diamond lattice. Distribution of annular structure and lineament hasstrong relativity. It mainly distributed in central eastern regions，circular structure gathered inthis area. Lineament intersection point density area has good correlation with copper and silvermineralization. The intersection of high density in circular structure has good relevance withhydrothermal type deposits，which can provide important information for predicting indicativeof hydrothermal deposits.（4）The study area of remote sensing mineralized alteration information are extractedby using multispectral and hyperspectral data. Comparing remote sensing mineralizedalteration information effect of OLI，ASTER multispectral data，by ratio method and themethod of principal component analysis，it conclude that interfere with the principalcomponent analysis method is superior to ratio method in the high vegetation coverage area.Hyperion hyperspectral uses spectral Angle mapping method and the method based onspectral identification extraction to exstract alteration minerals. We use spectral Anglemapping method to extract six kinds of altered minerals，such as dolomite，chlorite， illiteand montmorillonite，limonite，pyrite. Based on the other method，alteration information arealso exstracted. It increased four kinds of alteration mineral identification，such as dolomite， calcite，tremolite and kaolin. Hyperspectral data with the method of spectral Angle mapping，can carry on the effective identification of altered minerals.（5）The paper carries out romete sensing in biogeochemistry of mineral resources inporphyry copper concentrate distribution. There are Xuejiping，Pulang， Chundu，and Hongshan Porphyry copper deposit. Porphyry copper ore bodies buried in shallow，ore-formingelements and associated elementseasily can easily pass the underground water to soil cover，and absorbed by plants，produce toxic effects on plants. Based on the analysis of the fieldmeasured spectral curves of the Yunnanensis， fir，larch，mountain oak and rhododendron inthe area，dominant poisoned plant appeared blueshift phenomenon in different degree. Theremote sensing image gray value of these species is generally higher than the backgroundvegetation，gray value have great correlation with the Co，Cd elements in the plant leaf，Mnand Sb elements in the soil，which can provide the reference for the exploration of ore depositin high vegetation covered area.（6）Based on geology and remote sensing information，the paper analyses thedistribution features of the ore deposit，Permian and Triassic formation are the mainore-bearing rock strata. The Cenozoic，Mesozoic and Paleozoic rock are distributed in thestudy area. The ore-bearing rock rock mass is mainly Mesozoic Triassic rock mass. Depositmainly distributed in the edge of circular structures，lineament and circular structure crosssection，lineament intersection. Remote sensing mineralized alteration information which hassome indication of deposit mainly distributed around the ore deposit.which has certaininstruction function for deposit. The distribution features of the ore deposit can providereference basis for prospecting.