Shynkarenko S. Economic bounds of completeness of minerals' deposits' extraction on the coal mines of Ukraine.

In the thesis the problems are investigated connected with substantiating the coal deposits' extraction bounds depending on the state of a concrete enterprise from the standpoint of increasing the effectiveness of nature exploitation and decreasing the amount of coal losses in the depths. For evaluation the state of the coal mine as of the subject of nature exploitation index of economic reliability was proposed for the first time. This index synthesizes in itself three elements: index of technological reliability, economic level ratio and index of geological resources evaluation. This allows to characterize the state of a mine more completely than with using indexes of production costs, profitability etc. The economical mathematical model of the index of economic reliability both for a separate subdivision and for the mine as a whole was worked out. It was determined that the numerical value of this index for the mines of Ukraine varies in the range of 0,2 - 2,0. Small value of the index is an indirec t indicator of the mine's low perspectiveness and of necessity of great investment for utilizing it's potential reserves.