Practice and exploration of thematic geological mapping for Precambrian copper deposits in the Zhongtiao Mountain, Shanxi Province

The theory and method of thematic geological mapping for Precambrian copper Deposits in the Zhongtiao Mountain is a focus problem as to how to plan and implement geological mapping smoothly on the basis of basic geological mapping. On the basis of 1:50000 thematic geological mapping, such problems as to genesis of mineral deposit, genetic relationships of different types of copper deposits and structural framework in Zhongtiao Mountain can be easily solved. The metallogenic belt of the Zhongtiao Mountain is located in the southern orogenic belt of the middle part of the North China craton, where there occur the famous Tongkuangyu type, Hu-Bi type, Luojiahe type and Henglingguan copper deposits, in which Hu-Bi type copper deposits are distributed at the top of the Yuyuanxia Formation-the bottom of the Bizigou Formation, the center of the Bizigou Formation, and the top of the Bizigou Formation-the bottom of the Yujiashan Formation. According to the principle that the material composition and structure are closely associated with mineralization, the authors carried out 1:50000 thematic geological mapping. The geological maps are expressed by means of stratigraphic code and lithologic composition, which can objectively express the formation lithology of Yuanyuanxai, Bizigou and Yujiashan formations and structure. The above practice included such means as outcrop observation, mapping unit classification, and graphic expression of map for 1:50000 thematic geological mapping in Zhongtiao Mountain Precambrian copper deposits, and the results obtained provide implications for the present thematic geological mapping.