Abstract: The results of the geological exploration of deep resources at Miaogou Iron Mine are described, including the country rock properties, occurrence, thickness, wedging out, ore properties, structure and texture, and iron ore quantity of orebody II.The problems and solutions of this exploration and the issues needing to be considered after this exploration are discussed.Based on this, the economic benefits of the two methods of the transition from open-pit to underground mining are compared and it is concluded that the most rational plan is to transit the mining to underground at 372 m level.

Key words: Deep resource exploration, Mining transition mode, Thinking, Comparison