检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:WANG Xiaochun Intstitute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
出 处:《Chinese Science Bulletin》1999年第S2期21-23,共3页
摘 要:1 Geological features of fine disseminated gold deposits THE fine disseminated gold deposits occur mainly in the Indochina and Variscan fold belts along periphery of Yangtze plate, which constitute three concentrated regions including Sichuan-Gansu-Shaanxi, Yunnan-Guizhou-Guangxi and central Hunan regions. There are multiple mineralized strata from Sinian to Triassicof which Triassic and Devonian are chief ones. Ore-bearing rock series are mainly black carbon-bearingpelitic and sandy series. There are many kinds of host rocks for gold ores. Alterations such as silicification, carbonatization, argillation, chloritization and baritization occur in wallrocks. Ore bodies are closelyrelated to fractures, occurring in bedded ore veins. Major ore minerals are pyrite, arsenopyrite,
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.3