Geochemical characteristics of stream sediments and prospecting direction in the Shijinpo-Nanjintan area of Beishan, Gansu Province

Based on the result of the stream sediment survey in Shijinpo-Nanjintan area of Gansu Province, the authors studied the characteristics of the elements distribution, the single element anomaly and the element assemblage. According to the distribution of element anomalies, the types of assemblages and theanomaly controlling factors, thestudy area is subdivided into 11 anomalous zones. The eleven anomalous zones can be further divided into four types: the first kind of anomalies is related to the intermediate acid intrusive rocks and the fracture structures, and Au is the main metallogenic element. The anomalous zones are the potential areas of quartz vein type and broken belt type gold deposits. The second type of the anomalies is related to the formation of the Jixian system, and these anomalous zones are the important potential areas of Pb, Zn, Fe and polymetallic deposits. The third type of the anomalous zones is related to the Dunhuang system, and the anomalous zones are potential areas of metamorphic hydrothermal type gold deposits. The fourth type of the anomalous zones is related to the intrusion of basic-ultrabasic complex, and the anomalous zones are the potential areas of magmatic liquation Cu-Ni sulfide deposits.