The Tianshuihai-Lingyangtan Area of West Kunlun is in the Northern Karakoram,the average elevation of the area is more than 5000 m,the structure is very complex,the Qiao' ertianshan-Chalukou fault runs through the West Kunlun ar-ea,it is the dominating ore-controlling structure. The Pb-Zn mineralization is well developed in the area,the ferritization,ka-olinization and carbonatization are the major alteration types of surrounding rock. The advantage of Landsat 8-OLI data is supe-rior to Landsat ETM+ data in the detection of metallogenic hydrothermal alteration and lithological characteristics. So,Landsat 8-OLI data in study area is taking as the study data in this paper,through principal component analysis ( PCI) on Landsat 8-OLI data,and the band combination of OLI 2,4,5,6 and OLI 2,5,6,7 are selected to extract the alteration information of iron stained and hydroxyl separately. Taking the typical deposit ( Duobaoshan Pb-Zn deposit) in the study area as the study exam-ple,the remote sensing alteration information and the relationship between remote sensing alteration information and metallo-genic geological background are analyzed comprehensively,the remote prospecting model of Pb-Zn deposit in the study area is established,the model can be described as:①the alteration information of hydroxyl and iron stained are obviously distributed with long strip shape,which are good agreement with the main structures and its secondary structures;②the alteration informa-tion of iron stained is distributed along the fracture or the surrounding rock distributed at the both sides of the fracture,the al-teration information of hydroxyl is distributed on the periphery of the iron stained alteration. Based on the above analysis results,the two metallgoenic prospect areas are delineated by using anomaly method,among them,I# prospect area is located at the south of Qiao ’ertianshan-Chalukou fault,Ⅱ# prospect area is located at the northwest of the study area,ant is is distributed with NE-direciton. The filed verification results and the analysis results of X-ray fluorescence spectrometer and ASD spectrometer show that the Pb-Zn mineralization strength are basically consistent with the already existed ones obtained by geochemical prospecting method in the study area,they are both the favorable prospecting areas.%喀喇昆仑山脉北侧的西昆仑甜水海—羚羊滩地区平均海拔约5000 m,地质构造情况复杂,其中乔尔天山—岔路口断裂横穿整个西昆仑地区,是研究区最重要的导矿控矿构造.区内铅锌矿化发育,围岩蚀变类型主要为褐铁矿化、高岭石化、碳酸盐化.鉴于Landsat-8 OLI数据在成矿热液蚀变和岩性探测方面较Landsat ETM+数据更具有优势,故对研究区获取的Landsat-8 OLI数据进行主成分分析(Principal component analysis(PCI)),选取波段2、4、5、6和波段2、5、6、7组合分别提取铁染和羟基蚀变信息.通过综合分析研究区典型铅锌矿床——多宝山铅锌矿的遥感蚀变信息及其与成矿地质背景的关系,构建了研究区铅锌矿遥感找矿模型:①羟基、铁染蚀变呈明显的长条状展布,与主构造及次级构造吻合良好;②铁染蚀变沿断裂或其两侧的围岩分布,羟基蚀变则分布于铁染蚀变外围.在此基础上,利用类比方法圈定了2处成矿远景区,即I#远景区位于乔尔天山—岔路口断裂南侧,Ⅱ#远景区位于研究区西北侧,呈NE向展布.经野外验证及室内X荧光仪、ASD光谱仪测试分析,认为两处远景区铅锌矿化强度与区内已有的化探资料较吻合,为寻找铅锌矿床的有利区段.
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