Influence of structural framework of coalfield on physical properties and seepage characteristics of reservoir in Henan Province

In order to find out the characteristics of gas flow characteristics in coal seams in different tectonic zones in Henan Province and to discover the uniqueness of the structure and deformation of coal mass, based on the experimental data analysis and gas geology and seepage theory, the changes of pore volume distribution and pore sizes under the influence of stress as well as the deformation and failure characteristics of coal strength in coalfield under the action of tectonic stress were studied. The results of the study show that the ranking of the dominant sequence of methane flow in coalbed is Taihang tectonic belt > Xiaoxiong tectonic belt > Songqi tectonic belt. The differences of patterns of methane flow in coalbed were controlled by the regional tectonic deformation system, the tensile strain of coal mass in Taihang tectonic zones caused wide distribution rang of strength of coal mass, higher porosity and largest max volumetric strain, the gravity slide and shearing and extension deformation in Songqi tectonic belt brought out lowest strength of coal mass, lowest porosity and least maximum volumetric strain in the three coal seams, the maximum volumetric strain of coal mass in Xiaoxiong tectonic belt was between that of Taihang tectonic belt and Songqi tectonic belt. The conclusion has guiding significance for CBM development.