子区中位数衬值滤波法在川西斑岩型铜矿区地球化学异常的筛选与查证中的应用

THE APPLICATION OF THE SUBINTERVAL AREA MEDIAN CONTRAST FILTERING METHOD TO THE SIEVING AND INSPECTION OF GEOCHEMICAL ANOMALIES IN THE PORPHYRY COPPER ORE DISTRICT OF WESTERN SICHUAN

川西乡城—稻城—得荣地区地处川西高原,相对高差一般大于2 000 m,高山深切割现象显著。地质背景及表生地球化学环境复杂,找矿标志不明显,找矿难度大。采用传统化探方法可能漏掉部分强度不大而可能致矿的异常;或者是矿体有一定埋藏深度而异常较弱,由于未引起足够的重视而影响到找矿效果。子区中位数衬值滤波方法解决了低背景区和高背景区弱小异常的识别问题,克服了采用全区统一异常下限给异常识别带来的困难。

the Xiangcheng-Daocheng-Derong area is located in the western Sichuan continental platform, with the relative height difference more than 2000 m. In this area, dissection is deep, geographic conditions are unique, surface geochemical environment is complicated, and ore-prospecting indicators are not clear. All these factors make it difficult to find new deposits. Traditional geochemical data fail to find some anomalies related to mineralization. In some cases, ore bodies are deep and anomalies are weak, leading to ignoring the deposits. The subinterval area median contrast filtering method can solve the problem of recognizing weak anomalies in the low - back- ground area and high-background area.