基于MPT方法的遥感蚀异常信息提取和成矿预测——以青海大格勒沟地区为例

Remote Sensing Alteration Anomaly Information Extraction and Metallogenic Prediction Based on MPT Method——A Case Study of Dagelegou Area in Qinghai Province

MPT方法是基于“掩膜技术+主成分分析+门限化分级”数据处理流程的蚀变信息提取方法,其能够在有效排除植被、冰雪、水体等干扰信息基础上,定量提取主成分中弱蚀变信息并进行等级划分。本文以landsat8 OLI数据为基础,基于MPT方法提取了大格勒沟地区的铁染和羟基蚀变信息,并与已知地质背景进行了分析比较。结果表明,区内现有金多金属矿详查区内铁染和羟基综合蚀变异常信息与水系沉积物Au、Cu和Mo元素异常、铜金矿体以及断裂破碎蚀变带分布吻合程度高,遥感蚀变异常信息能够有效指示矿化部位。基于综合蚀变异常信息、异常验证分析结果和区域地质背景,圈定了5个成矿远景区,为该区下一步找矿工作提供了参考。

MPT method is an alteration information extraction method based on the data processing process of "mask technology + principal component analysis + threshold classification". It can quantitatively extract the weak alteration information in principal components and classify them based on the effective exclusion of vegetation, ice, snow and water. In this paper, based on Landsat8 OLI data and MPT method, iron staining and hydroxyl alteration information in Dagelegou area were extracted and compared with the known geological background. The results showed that the comprehensive alteration anomaly information of iron staining and hydroxyl in the existing gold polymetallic ore detailed survey area were highly consistent with the distribution of Au, Cu and Mo anomalies in river sediments, copper and gold orebodies and fracture alteration zones, and the remote sensing alteration anomaly information could effectively indicate the mineralization location. Based on the comprehensive alteration anomaly information, anomaly verification analysis results and regional geological background, five metallogenic prospects were delineated, which provided reference for further prospecting work in this area.