Extraction of deep mineralization information from weak and low tectono-geochemical anomalies: A case study of the Maoping germanium-rich lead–zinc deposit in northeastern Yunnan Province, China

Abstract

Tectono-geochemical analysis is one of the key technical methods for deep prospecting and prediction, but the extraction of information on weak and low degrees of mineralization remains a significant challenge. This study takes the Maoping super-large germanium-rich lead–zinc deposit in northeastern Yunnan as an example, systematically analyzes the mineralization element assemblages and their anomaly distribution characteristics, extracts information on low and weak anomalies at depth, clarifies the spatial distribution of ore-forming element anomalies and fluid migration patterns, and establishes tectono-geochemical deep anomaly evaluation criteria and prospecting models, thereby proposing directions for deep prospecting in the deposit. This research shows that the mineralization element assemblage of the F1 factor (Cd-Cu-Ge-Zn-Sb-In-Pb-Sr(-)-As-Hg) anomalies represents near-ore halos; the element assemblage of the F2 factor (Ni-Co-Cr-Rb-Ga) anomalies represents tail halos; the element assemblage of the F3 factor (Rb-Mo-Tl-As) anomalies represents front halos; and the element assemblage of the F4 factor (Ba-Ga) anomalies represents barite alteration anomalies. Elements such as Zn and Pb exhibit significant anomalies near the lead–zinc ore bodies. In the study area, vertical anomalies in the eastern region of the Luoze River indicate that ore-forming fluids migrated from the SE at depth to the NW at shallower levels, whereas in the western region, ore-forming fluids migrated from the SW at depth to the NE at shallower levels. Thus, the lateral extensions of different ore bodies in the eastern and western regions of the river have been determined. On this basis, tectono-geochemical deep anomaly evaluation criteria for the deposit are established, and directions for deep prospecting are proposed. This study provides scientific value and practical significance for deep prospecting and exploration engineering planning for similar lead–zinc deposits.