Geological modeling of shaft pillars parameters during mining operation of rich iron ores deposits under pressure aquifers

Abstract

Mining companies are increasingly forced to involve in the exploitation deposits with unfavorable geological especially hydrogeological conditions in order to maintain production capacity. An example of this is start of mining operation of the Pereverzivsky rich iron ore deposit at the Zaporizhzhya Iron Ore Plant. The ore bodies within this deposit are covered with a thick layer of sedimentary rocks, which contain pressure aquifers. Safe and complete mining of the deposits depends on the correct choice of shaft pillars parameters taking into account geological factors. A method for calculating shaft pillars parameters for the safest and most complete deposits development under aquifers has been determined. The technique is based on the results of three-dimensional models of rock complexes and ore bodies. The technique has been tested in difficult mining and geological conditions of the Pereverzivske rich iron ores deposit. According to the calculations, the minimum thickness of the protective layer will be: Option 1 camera width 15m - the worst conditions - 27.8 m; the best conditions - 3.6 m; average conditions - 10.1 m. Option 2 camera width 30m - the worst conditions - 54.3 m; the best conditions - 4.3 m; average conditions - 16.5 m.