The Theories and Technological Practices in the Exploration of Deep-Covered Skarn-Type Rich Iron Deposits

Iron ore is a crucial bulk mineral necessary for the country’s economic development. In recent years, the discovery of a cluster of rich iron ore deposits under deep cover conditions in the eastern region of China has provided a new direction for exploring rich iron ore deposits in northern China. This paper is based on the preliminary low-amplitude magnetic anomaly verification work conducted in the Dezhou area of Shandong Province, China. It systematically summarizes the metallogenic theory of siliceous iron ore in this area, establishing a four-tier progressive exploration method. Addressing the challenge of locating ore bodies in deep-cover areas, there have been significant breakthroughs in extracting various weak signals in geophysics. This has led to the development of a collaborative three-dimensional exploration system based on the integration of airborne, ground, and borehole data involving gravity, magnetic, electrical, and seismic information. Building upon this research foundation, various exploration activities were undertaken, culminating in the implementation of nine validation boreholes. Among these, seven encountered ore bodies, and two revealed mineralization. This indicates the excellent practical application and promotional value of the metallogenic theory and prospecting techniques for siliceous iron ore deposits in deep-covered areas.