The application of geophysical and geochemical exploration and metallogenic prediction in the Wangjiagou gold ore district of Mianxian County, Shaanxi Province

Abstract：Based on a study of regional metallogenic regularity, this paper summarizes the prospecting criteria for the southern metallogenic belt in the Mian-Lue-Ning triangle area as follows: ① strata composed of Proterozoic basement metamorphic volcanic rocks and adjacent clastic rock and carbonate rocks; ② well-developed NE-NNE trending faults; ③ areas where fractures are filled with intermediate-basic veins; ④ geochemical anomaly areas of such elements as Au, Ag, Cu and Zn. The authors analyzed the metallogenic conditions of the study area and considered that the study area had favorable conditions in search for gold deposits related to fractures. First, using the IP intermediate gradient method, the authors quickly and accurately delineated two parallel NE-trending anomaly zones (No.Ⅰ, No. Ⅱ) which had high polarizability and low resistivity, and then disposed two polarization pole-dipole array sounding and soil geochemical profiles perpendicular to the anomaly zones. Combining geological data with interpretation, the authors predicted that the two anomaly zones were caused by two concealed ore-bearing fractures. Using adit engineering under the No.Ⅰ anomaly zone, the authors found a quartz vein type gold ore body which contained polymetallic sulfides. It is thus inferred that there exists a larger gold ore body under the No. Ⅱ anomaly zone, which has stronger and greater anomaly intensity than No.Ⅰ.