东天山帕尔岗塔格西斑岩铜矿高光谱遥感蚀变特征及其对找矿的指示意义

Hyperspectral Remote Sensing Alteration Characteristics of the Paergangtagexi Porphyry Copper Deposit in Eastern Tianshan Mountains and Their Indicative Significance for Prospecting

帕尔岗塔格西斑岩型铜矿位于东天山古生代造山带小热泉子石炭纪岛弧带,带内已发现有土屋、延东、延西等一系列斑岩型铜矿,成矿潜力巨大,该矿床的发现实现了成矿带的北西向延伸,意义重大。目前勘查工作限于矿区西北部,找矿勘查有待进一步探究,且针对该矿床的高光谱遥感研究未有报道。鉴于此,本文基于ZY1-02D高光谱数据,采用“人机交互式”思维指导下的基于纯净像元指数(PPI)算法的端元波谱提取技术,从矿物角度对矿区及其外围进行蚀变信息提取工作。提取结果显示三种蚀变矿物由内向外呈石英-绢云母-绿泥石的顺序分带,再现了矿区地质填图工作中的蚀变分带特征,并在矿区外围发现了一处受断裂控制的蚀变分带区,成矿特征明显。野外调研和样品岩相学分析证明提取结果真实有效,本次研究可为矿床下一步勘查工作提供参考。

The Paergangtagexi porphyry copper deposit is located in the Xiaorequanzi Carboniferous island arc belt of Paleozoic orogenic belt,eastern Tianshan Mountains.A series of porphyry copper deposits,such as the Tuwu,Yandong and Yanxi,have been discovered in the belt,with a great ore-forming potential.The discovery of this deposit has realized the NW extension of the ore-forming belt and is of great significance.At present,the exploration work is limited to the northwest of the mine area,the exploration needs to be further explored,and hyperspectral remote sensing research on the deposit has not been reported.In view of this,based on ZY1-02D hyperspectral data and guided by"human-computer interactive"thinking,this work used the pure pixel index(PPI)algorithm to extract alteration information from the mining area and its periphery from the perspective of minerals.The extraction results show that the three altered minerals display an outward zonation of quartz-sericite-chlorite.These results reappear the alteration zonation characteristics in the geological mapping of the mining area,and an alteration area controlled by fault is discoverd in the periphery of the mining area,with obvious metallogenic characteristics.Field investigation and sample petrographic analysis prove that the extraction results are true and effective,and this study can provide reference for the next exploration of the deposit.