Geochemical characteristics of stream sediments and ore-prospecting orientation in Daba Mountain area

The Daba Mountain passes through two tectonic units, namely, the Qingling orogenic belt and the Yangtz craton. Based on the 1:50000 stream sediment survey, the authors calculated the geochemical parameters of ore-forming elements and analyzed the distribution characteristics, element correlation and element anomaly assemblages. The results show that the study area might be a potential area for Pb, Zn, Ba, Cu and Mn deposits. It is concluded that the main metallogenic types in Qinling unit of the study area are low temperature epithermal Zn-Cu deposits and sedimentary type Ba deposits connected with the Silian-lower Cambrian black rocks. The main metallogenic types in Yangtze unit of the study area are low temperature epithermal Pb-Zn deposit related to the Cambrian carbonaceous rocks and sedimentary type Mn deposits which are connected with Cambrian and Silian carbonaceous rocks respectively. On such a basis, five prospective areas were delineated. Yangjiaping-Gedong area and Zhenping area are expected to be promising areas for Ba-Zn deposits, Huang'anba-Mihunzhen area for Zn-Cu deposits, Baiyangping area for Pb-Zn deposits and Xiuqi-Shifang area for Mn deposits.