The perspective and prognostic areas of zinc and lead ores in the Upper Silesia Zn-Pb Ore District

Abstract

The largest perspective of zinc and lead ore resource are located in the area of Upper Silesia District, where in the Middle Triassic and Devonian carbonate rocks occurs Zn-Pb sulfide ore mineralization of the Mississippi Valley Type (MVT). Prognostic amounts of Zn-Pb ores resources estimated in the Olkusz region are close to 50 million tons, and in the Zawiercie region 15 million tons. Actually, a total of prognostic resources of sulfide Zn-Pb ores represent 76-84.3% of all economic documented deposits. Zn-Pb sulfide ores resources have been verified according to the criteria from 2007 and their quantity evaluation based on autocorrelation around the boreholes locating economic mineralisation. In the zones of documented deposits a significant increase of resources is expected, because the actual data are based on too rare drilling grid. It is appropriate to carry out further geophysical works (e.g. IP - Inductive Polarization method) and, anomalous areas should be explored by drilling. Oxidized Zn ore resources (galman) in the deposits are 51.19 million t and in mining wastes 9.64 million t and are ca. 30% less than the Zn-Pb sulfide ore resources in documented deposits. The galmans occurring in the Upper Silesian district due to low quality, environmental laws and conflicts with the spatial economy are not currently the subject of exploitation. The galman ore resources in undeveloped deposits require verification of resources in accordance with the new economic criteria.