Dependence of the mined ores quality on the geological structure and properties of the hanging wall rocks

Abstract

Paper presents the research results of the relationship revealed between the mined ore dilution factors and the geological structure and properties of the hanging wall rocks. The research methodology is in the analysis of the structure and properties of the hanging wall rocks, the technological parameters of the stopes in contact with the host rocks, the processing of actual surveying data of the rockfall volumes and dilution factors, the construction of a 3D model of the mined floor with the stopes divided according to the sequence of mining. The peculiarities have been revealed of changing the geological structure along the strike of the ore deposit with a characteristic distinguished tendency to decreasing the hardness of hanging wall rocks, the angle of the ore deposit slope, increasing the deposit thickness and replacing the morphological composition of the rocks with the division into 3 characteristic differing areas. New patterns and empirical equations have been determined for changing the ore dilution value in the primary stopes depending on the type, hardness coefficient and the contact area of the hanging wall rocks with the inclined outcropping of the stopes. A multiple regression equation has been obtained of the relation between the primary stopes dilution with the rocks hardness within f = 11 – 15 and the contact area of the stopes with rocks 780 – 2010 m2. The regression model variability of 85.96% evidences its reliability and representativeness. The methodological approach proposed in the paper can be used to develop an improved methodology for predicting the mined ores dilution when mining the Pivdenno-Bilozirske field, supplemented by a more complete data set to increase reliability.