甘肃白银厂矿区及其外围铜矿床成矿特征与定量预测

Metallogenic characteristics and quantitative prediction of Cu in Baiyinchang and its periphery area

北祁连地区是我国重要的海相火山成因铜多金属块状硫化物矿床成矿带,位于该区东段的白银矿田内产出有多个大型-特大型VMS矿床,具有较好的找矿前景。在该地区铜矿床成矿特征研究的基础上,利用GIS技术提取与成矿有关的地层、构造、岩浆岩、地球化学等多元找矿信息,构建了白银矿区及外围铜矿床的证据权重找矿模型,利用后验概率圈定出找矿远景区,按照各找矿远景区相对成矿可能性的大小和各找矿标志将远景区分为Ⅰ、Ⅱ、Ⅲ3级,各级找矿远景区各3个。

The northern Qilian area was the important Cu polymetallic metallogenic belt of marine volcanic massive sulfide deposit in China. Baiyinchang district was located in the east section of the study area and hosted some super-large scale or large sized VMS ore deposit, hence it was the potential area for further exploration. Based on the analysis of metallogenic characteristics in the area, the multivariate data related with the mineralization, such as strata structures, magmatic rocks, geochemistry, etc, were extracted by means of the GIS technology. After obtaining aforementioned information, the mineral deposit quantitative prospecting model was established by using weights of evidence method. Some potential areas were marked out by calculation of the posterior probability. According to the relative possibility magnitude of mineralization geological conditions among the potential areas and the indicator for deposit, the potential areas were divided into three grades and symbolized by I, II and III, respectively, and three potential areas for each class ore prospect.