Three-dimensional visual prediction of concealed ore bodies in the deep and marginal parts of crisis mines: a case study of the Fenghuangshan ore field in Tongling, Anhui, China.

By taking the Fenghuangshan ore field in Tongling, Anhui as a case study, the concept model for ore body location predication was built through the general geological investigation of the ore field. Based on the integration of geological geophysical and geochemical exploration data, the geological bodies such as strata, structures, magmatic bodies and ore bodies were inferred and delineated by means of three-dimensional geological modeling, and then the wireframe and block models of the geological bodies were constructed. From the concept model of location predication and the 3D block models of geological bodies, we've obtained the three-dimensional raster models of the geological ore-controlling fields of the magmatic body and its surface relief, the contact zone, the strata, the folds, the faults and so on. By analyzing quantitatively the correlation relationship between the geological ore-controlling factors and the mineralization distribution, the stereoscopic quantitative predication models of ore bodies to reflect the relationship were set up. With the predication models, the predication results, including copper grade and copper tonnage of all cubic cells with size of 50m×50m×50m in the deep parts (above the elevation -1000m ) of ore field were provided. On the basis of the predication results, 4 cubic target areas for deep prospecting were delineated, which provides guidance on the location, grade, tonnage and other information of undiscovered concealed ore bodies for the design and layout of deep prospecting engineering.