APPLICATION OF PRIMARY HALO IN DEEP METALLOGENIC PREDICTION: A Case Study of Yongxin Gold Deposit in Heihe Area

Primary halo has proved to be an effective geochemical exploration method for concealed orebodies prediction and prospecting by a number of long-term practices. Based on the exploration of Yongxin gold deposit, the paper analyzes the primary halo of drill holes by collecting rock samples from four boreholes along the No. 180 exploratory line with the best ore-discovery in the area. The results define the front halo element association of As-Sb-Hg, near-ore halo of Au-Ag-Cu-Pb-Zn and rear halo of W-Mo-Bi-Co-Ni-Cd. Compared with the typical zoning model of gold deposits summarized by previous researchers, the existence of rear halo elements in front halo and the front halo elements also in rear halo sequence shows the reverse zoning feature, indicating the blind ores exist in both the upper and lower of orebody. As the blind ores in the upper part to southeast has been denuded according to the orebody developing form, further exploration should focus on the lower part to the northwest.