The progress in the study of the Boroo gold deposit in Mongolia
CHEN Long;ZHAO Yuanyi;China university of Geosciences(Beijing);Institute of Mineral Resources,Chinese Academy of Geological Sciences;
The Boroo gold deposit, located in northern Khentei gold ore belt, is the first hard rock gold deposit discovered in Mongolia, 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(anomalous gold values ≥ 100ppb) is more than 2500 m, the width is at least 400 m, and the thickness is locally as large as 100 m. 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 Jinshan 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 35 km away from the Boroo deposit, which shares the same deposit type and equal ore reserves. On the basis of previous researches, the authors 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.