Regional distribution and geotectonic control of Late Permian tectonically deformed coal in Zhina coalfield

In order to find out the tectonically deformed coal distribution law of Zhina coalfield, by sorting out and analyzing the data of more than 200 coal-bearing structural units including Bide syncline, Santang syncline, Zhuzang syncline, Arcong syncline and Guanzhai syncline in Zhina coalfield, Guizhou Province, combined with logging curve analysis, the regional distribution characteristics of coal body structure and structural control factors of No.6, No.16 and No.27 main coal seams are comprehensively analyzed. The study shows that from the west to the east, the proportion of tectonically deformed coal in Zhina coalfield increases gradually. The coal in the western part is mainly composed of undeformed coal and fragmented coal and the coal in eastern part is mainly composed of granulated coal and pulverized coal. The distribution of tectonically deformed coal is mainly affected by tectonic evolution and four deep faults. The multi-phase tectonic movement caused multi-stage deformation of tectonically deformed coal, while the Yanshanian period was the main stage of tectonic deformation of coal seams, the early tectonic deformation was superimposed in the Himalayan period. The distribution of regional stress fields was affected by deep faults. Zunyi-Huishui fault had the greatest influence on the formation and distribution of tectonically deformed coal. The regional stress field from the east to the west in the early Yanshan period was blocked by Zunyi-Huishui fault, thrust, reverse faults and other structures developed under the violent effect of folds and faults in the eastern part of the coalfield, and the coal structure was seriously damaged, granulated coal and pulverized coal developed. This study has guiding significance for prevention and control of gas disasters, the exploration and development of coalbed methane in Zhina coalfield.