新疆南天山某金矿蚀变信息提取研究

On the Alteration Information Extraction of a Gold Mining Area in the South Tianshan Mountain in Xinjiang

以新疆南天山成矿带某金矿区作为研究对象,基于围岩矿化蚀变理论,利用TM数据对矿化区异常蚀变信息进行提取.矿化蚀变信息是遥感找矿的重要标志之一,蚀变信息的提取可以为野外地质找矿提供重要靶区.基于新疆南天山的地质情况和自然条件,选取南天山某金矿区TM影像数据对其进行蚀变信息提取处理,并对矿区铁染和羟基蚀变进行分级.在总结和参考前人蚀变提取的技术方法基础上,对TM数据首先进行几何校正、大气校正、掩膜(去除植被、水体和阴影的干扰)等预处理,而后运用最经典的蚀变提取方法—Crosta主成分分析法,最后用密度分割的方法对矿区进行铁染和羟基蚀变划分,并划分为三个等级.

Basing on the theory of mineralized alteration surrounding rock,we put the gold mining area as the research object in south tianshan metallogenic belt in xinjiang and extract abnormal alteration information for TMimage in the zone of mineralization.Mineraliza-tion alteration information is an important sign of remote sensing prospecting,it can provide important target for field geological prospec-ting.We deal with TM image data for alteration information extraction in south tianshan mountain gold mining area under the back-ground of geological condition and natural condition.Firstly we take a way of geometric correction.atmospheric correction and maskpro-cessing （removal of vegetation,water body and shadow interference）for TM image.Secondly,we use the classic alteration extraction method ——— Crosta principal component analysis （pca）.Lastly,we divided into three grades of iron stain and hydroxyl alteration a-nomalies by the method of density slice.