西昆仑地区水系沉积物地球化学异常识别

The identification of stream sediment geochemical anomalies in West Kunlun region

采用子区中位数衬值滤波法和异常下限衬值滤波法对西昆仑地区1∶20万水系沉积物测量数据进行处理,分别圈定了各元素的衬值异常,并在此基础上将两种方法所获衬值异常的叠合部分作为新的异常边界,重新圈定单元素异常和多元素组合异常。研究表明,该方法能更好地识别异常,根据异常区元素浓集特征并结合区域地质背景,认为区内Au、Ag、Cu、Pb、Zn、Sb、Sn、W具有较明显的成矿潜力与找矿前景,在找矿方面应重点寻找热液型铜多金属矿、热液型铅锌矿、热液型锑矿、花岗岩型钨锡矿、斑岩型铜矿以及岩金矿床。

Based on the data of the 1∶ 200 000 geochemical stream sediment survey,the authors delineated the single element contrast value anomaly by using the method of ＂ subinterval area median contrast filtering＂ and ＂ outlier contrast filtering＂ respectively. The overlap contrast value anomalies by the two methods were taken as a new anomaly border to re-delineate single element anomaly and multi-element association anomaly. This study indicates that,by the spatial overlay analysis of contrast value anomalies obtained by the two methods,the overlapped portion can be more effectively identified for the anomaly. According to anomaly characteristics of the concentration elements and regional geological background,It is held that this area has obvious potential mineralization and ore prospects of Au,Ag,Cu,Pb,Zn,Sb,Sn,W,and the prospecting work should focus on hydrothermal Cu polymetallic ore deposit,hydrothermal Pb-Zn ore deposit,hydrothermal Sb ore deposit,granite-type W-Sn ore deposit,porphyry Cu ore deposit and rock gold ore deposit.