证据权法在成矿预测中的应用——以湖北通城地区铍矿的成矿预测为例

Application of the Weight-of-Evidence Method in Metallogenetic Prediction——A Case Study of Prospecting of Beryllium Deposits in Tongcheng,Hubei Province

应用证据权法和MORPAS GIS技术开展了通城地区铍矿的成矿预测研究。在总结通城地区区域地质背景和预测准则的基础上,通过建立通城地区地质、矿产、物探、化探、遥感等基础空间数据库,综合分析多源数据,运用MORPAS矿产资源评价系统提取与铍矿相关的信息,采用证据权法对铍矿有关的证据图层进行系统的分析和处理,编制成矿后验概率等时线图,最后根据高值区圈定了找矿远景区。此次预测工作共选出15个证据因子层,对该地区以铍矿为主的稀有金属矿床进行了定量预测,最终圈定了两个远景区。该两处远景区与己知铍矿点具有相似的成矿条件,应在今后的勘探工作中引到足够的重视。

The weights-of-evidence method and MORPAS GIS were applied to delineate prospecting targets of beryllium deposits in Tongcheng, Hubei province. Based on summarizing regional geological background and basic forecasting criteria, basic spatial databases of geological, commodity, geophysical, geochemical, and remote sensing in Tongcheng area are established for metallogenic prognosis with GIS technology. Beryllium deposit-re- lated information is extracted by MORPAS mineral resources evaluation system. Systemic analysis and Processing of evidential layers related to beryllium deposits were carried out by the weights-of-evidence method. The contour map of the posterior probability of Beryllium deposits prediction in Tongcheng area is employed to delineate the prospecting area. We select 15 important layers from all data as evidence factors to predict beryllium deposits, and two Metallogenetic prospective areas in Tongcheng area are found. Because of the similar metallogenic condition with known mineral deposits, those two prospect targets deserving more and adequate attention in future explo- ration.