Metallogenic model of the Wulong gold district, China, and associated assessment of exploration criteria based on multi-scale geoscience datasets

摘要

The combined use of geological and geophysical modeling is effective for delineating subsurface exploration criteria and conducting quantitative analyses to determine potential mineral targets. In this paper, total horizontal derivative, multi-scale edge detection (worms), and bi-dimensional empirical mode decomposition (BEMD) of district-scale gravity and magnetic data were applied to extract geophysical information reflecting deep-seated structures and concealed intrusions. In addition, deposit-scale 3D modeling and controlled-source audio-frequency magnetotelluric data were used to identify potential ore-controlling structures. The results of our integrated multi-scale geological and geophysical studies suggest that the Early Cretaceous intrusions and gold deposits in the Wulong gold district, which is located on the Liaodong Peninsula, China, at the NE margin of the North China Craton (NCC), are spatially and genetically associated with a network of NE- and NW- striking faults. Gravity and magnetic modeling effectively identified buried Early Cretaceous intrusions and NW- striking faults at depths from zero to five kilometers. In summary, the combined use of multiple-source and multi-scale geophysical information and multi-scale 3D geological modeling facilitated delineation of the metallogenic model and provided exploration criteria for determining potential exploration targets in the study area.