川北旺苍—南江石墨矿带地质特征与找矿潜力

川北旺苍—南江石墨矿带位于米仓山隆起南缘,是中国重要的石墨成矿带之一,石墨矿赋存于中-上元古界火地垭群麻窝子组碳酸盐岩—碎屑岩变质岩系,石墨矿床以沉积—变质型为主。矿带东段已发现尖山、坪河、庙坪等中-大型晶质石墨矿床,已探获资源量近1000万t;矿带西段有大河坝、大营河坝等9处石墨矿点,其中大河坝矿点最具找矿潜力。为促进矿带石墨找矿勘查工作,在对矿带成矿地质背景、矿带地质特征及控矿因素研究的基础上,圈定了石墨找矿靶区3处,并通过验证在矿带西段大河坝发现了晶质石墨矿体,主矿体长约3 km,平均厚度23 m,固定碳品位15%,表明旺苍—南江石墨矿带具有较大的找矿潜力。

Geological characteristics and prospecting potential of graphite metallogenic belt in Wangcang-Nanjiang, North Sichuan Province

The Wangcang-Nanjiang graphite metallogenic belt in northern Sichuan is located in the southern margin of the Micangshan Uplift. It is one of the important graphite metallogenic belts in China. Graphite deposits occur in the Mawozi Formation carbonate-clastic metamorphic rock series of Huodiya Group in the Middle-Upper Proterozoic. The graphite deposits are mainly sedimentary-metamorphic. In the eastern section of the metallogenic belt, large and medium crystalline graphite deposits have been found, such as Jianshan, Pinghe and Miaoping. Nearly ten million tons of resources have been identified;There are nine graphite ore points in the west section of the ore belt, such as Daheba and Dayingheba. Among them, Daheba ore site has the most prospecting potential. In order to promote the prospecting and exploration of graphite ore in ore belt ,three targets of graphite ore prospecting are delineated on the basis of the study of metallogenic geological background, geological characteristics of ore belt and ore controlling factors. The crystalline graphite orebody was found in Daheba in the west section of the ore belt. The main ore is about 3 km, average thickness 23 m, fixed carbon grade 15%. It indicates that Wangcang-Nanjiang graphite metallogenic belt has great prospecting potential.