Prospecting criteria for skarn-type iron deposits in the thick overburden area of Qihe-Yucheng mineral-rich area using geological and geophysical modelling

The gravity and magnetic anomalies in the Qihe-Yucheng mineral-rich area of Shandong Province, China, lie nearly north–south. However, the anomalies in the Pandian area in the central part of the region are small in scale and weak in intensity, and the geophysical information of deep iron ore bodies is greatly weakened, making it difficult to identify and extract mineral-induced magnetic anomalies. Based on the exploration of gravity and magnetic anomalies in adjacent mining areas, and through plane analysis and quantitative inversion of these anomalies in the Pandian area, the structural framework division, delineation of ore-forming geological bodies, anomaly analysis research, and two-and-a-half dimensional (2.5D) joint inversion in the study area were achieved. Deep information under an ultradeep overburden was obtained, and a new breakthrough in the exploration of skarn-type iron ore was achieved. The results of this study can provide important references for further exploration of deep ore deposits under ultra-deep overburden layers and indicate the potential for the exploration of skarn-type iron deposits in the Qihe-Yucheng mineral-rich area. •The joint analysis of gravity and magnetic is a suitable method in this area.•The results reflect the vertical depth characteristics of ore-forming geological bodies.•Transform oblique magnetization magnetic anomaly into gravity anomaly is better.•The geological bodies may be located in the north-south neutral magmatic rock belt.