甘肃北山及其邻区钨钼化探异常特征及其成矿规律

Characteristics of Tungsten & Molybdenum Geochemical Anomalies and Their Ore-Forming Regularity in Gansu Beishan and Its Adjacent Area

采用趋势面分析方法对甘肃北山1:20万化探数据进行了处理后,所圈定出的一批W、Sn、Mo、Bi趋势剩余异常,不论从其空间分布特征、元素组合特征、与地层岩性、断裂构造、岩浆岩的关系分析,还是与已知矿床(点)的吻合对应情况来看,都与研究区地质情况吻合较好。通过典型矿床地质特征的论述后指出,北山地区钨钼矿的产出,W、Sn、Mo、Bi趋势剩余异常的空间展布受地层岩性、断裂构造、岩浆岩控制明显。不同的大地构造环境和不同的构造演化阶段决定了本区地层、构造、岩浆岩的产出特征,进而决定了本区W、Sn、Mo、Bi趋势剩余异常的组合及产出特征,当上述3个条件耦合在一起时,则形成规模大、类型复杂、有用组分多的中—大型多金属矿床。同时,在一些老矿区及其周边圈定了一批W、Sn、Mo、Bi趋势剩余异常,异常形态规整,趋势剩余明显,建议加强老矿区的综合研究工作,以加强危机矿山二轮找矿及资源综合利用工作。

The authors have located some trend remaining geochemical anomalies of W,Sn,Mo,Bi in the region of Gansu Beishan and its adjacent area by trend surface analysis of geochemical exploration data with scale of 1：200000.The distribution and the element association of the anomalies correspond to geological conditions of the region including three factors which are the special rocks within certain strata,certain fault structures,certain acid intrusions;and also correspond to the ore deposits found.The study results of typical tungsten ore deposits in the region show that the distributions of the ore deposits and the anomalies are controlled by the three factors;and big scale ore deposits are usually located in the area where the three factors overlap.The types of the deposits are complex,and ore in these deposits contains more useful components.According to some of the anomalies with regular ship and high content distributing at old mines of other metals and their surrounding areas,the authors suggest that prospecting work for W and Mo should start in these areas,and that recover W and Mo from these ore deposits should be taken notice of.