蒙古博洛金矿床研究进展

The progress in the study of the Boroo gold deposit in Mongolia

博洛(Boroo)金矿是蒙古国发现的首个岩金矿床,同时也是该国开采规模与黄金产量最大的金矿。该矿矿体主要产于博洛近水平断裂带内,整个矿化带(Au异常≥100×10^(-9))长度超过2000m,宽度400m,局部厚度达100m,主要围岩为博洛花岗杂岩、变质沉积岩等。矿床主要矿化类型有金-硫化物、金-石英脉型矿化2种,与中国典型超大型造山型金山金矿具有较多相似点,判定其为造山型金矿。距博洛金矿35km处产出同类型且储量相近的大型金矿—盖特苏尔特(Gatsuurt)。在已有研究的基础上,从产出环境、地质特征、矿床成因等方面对其进行了介绍和总结,并在矿床邻区内划定3个找矿战略靶区,这对中国企业在蒙古寻找同类型金矿具有指导意义。

The Boroo gold deposit, located in northern Khentei gold ore belt, is the first hard rock gold deposit discovered in Mongo- lia, and its scale of mining and the gold production are also the largest （averagely 3.52g/t gold, with total produced gold reaching 66t） . The deposit is hosted in the Boroo fault, a nearly flat-lying fault zone. The total combined length of the mineralization zone （anoma- lous gold values ≥100ppb） is more than 2500m, the width is at least 400m, and the thickness is locally as large as 100m. This area is underlain by granitoids of the Boroo Complex and metasedimentary rocks. Two main types of mineralization have been recognized in the Boroo gold deposit： the gold-sulfide type and the gold-quartz vein type. A comparison of the Boroo deposit with China＇s Jin- shan gold deposit shows that there exist many similarities between these two deposits, and hence the authors consider that the Boroo gold deposit is an orogenic gold deposit. Meanwhile, there is another large-sized gold deposit called Gatsuurt gold deposit 35kin away from the Boroo deposit, which shares the same deposit type and equal ore reserves. On the basis of previous researches, the au- thors have made a detailed summarization in the aspects of production environment, geological characteristics, and genesis of the deposit. This paper provides useful information for Chinese companies＇ prospecting for the same type gold deposits; in addition, three strategic targets in the adjacent areas of Boroo have been delineated.