Application of Mechanical Logging for Refining the Structure of the Olon-Shibirsk Coal Deposit

Abstract

When mining coal, detailed geological information on the structure of the coal-bearing strata and the quality of coal seams minimizes the risks associated with complicating mining and geological factors and changes in coal quality characteristics. The experience of using the mechanical logging method as an express method of operational exploration at the Olon-Shibirsk coal deposit is considered. Mechanical logging data were compared with core sampling and well logging data. As a result, the criteria for dividing the coal-bearing strata of the deposit into lithotypes were identified. According to these criteria, a general pattern can be distinguished for the considered coal-bearing strata: with a decrease in the dimension of the grains that make up the rock the drilling speed increases; with an increase in the content of organic matter in the rock, the drilling speed also increases and the maximum drilling speed characterizes coal seams. Drilling speed is a defining parameter, while other drilling parameters supplement its readings in case of ambiguity when interpreting the graph. For coal seams, the dependence of the drilling speed on the ash content of the seam was determined. At the same time, the dependence is most precise for seams with a thickness of more than 1 m. Based on the data of operational exploration using mechanical logging the morphology of coal seams and the complexity of their structure and ash content have been clarified for some areas, making it possible to clarify the reserves and quality for geological blocks. The final comparison confirmed the increase in the counting accuracy using the mechanical logging method. The practical significance of the research lies in improving the quality of operational exploration in the deposit while reducing costs.