Application of electrode potential logging in the exploration of low-grade type gold deposits: A case study of the Baoxinggou gold deposit

This paper is the result of mineral exploration engineering.

Objectives Aimed at addressing the challenges of weak geophysical signals, low signal-to-noise ratio, and high exploration difficulty in low-grade gold deposits, this study focuses on the precise identification of favorable mineralization horizons to provide an effective methodological support for gold exploration. The Baoxinggou gold deposit is a typical large-scale disseminated epithermal gold deposit, with an average grade of 1.43 ppm. It is hosted within the clastic sandstones of the Middle Jurassic Ershierzhan Formation. Taking the Baoxinggou gold deposit as an example, it investigates how to utilize geophysical logging techniques to establish identification criteria for favorable mineralization horizons applicable to this type of deposit.

Methods Systematic multi-parameter geophysical logging was conducted in two boreholes within the Baoxinggou gold mining area. By integrating data from drill core logging and sample analysis, the logging response characteristics corresponding to different gold enrichment levels were compared and analyzed. Through quantitative analysis of the correlation between gold grade and the amplitude of electrode potential anomalies, identification criteria for favorable mineralization horizons based on electrode potential logging were established.

Results The strata exhibiting metallic mineralization or intense alteration display serrated anomalies in electrode potential logging curves. Within these anomalies, multi-peak high-amplitude segments correspond to favorable mineralization horizons of disseminated ore bodies. In gold-enriched zones, the electrode potential curves exhibit intensive pulse-shaped or individual broad-amplitude anomalies, whereas barren zones are characterized by sparse sharp pulse-shaped anomalies.

Conclusions The identification criteria for favorable mineralization horizons established based on electrode potential logging can effectively delineate gold-bearing layers, enabling precise near-surface prospecting and providing a reliable basis for drilling program design. This research not only applies to shallow mineralization identification but also offers methodological guidance and practical reference for deep mineral exploration.