Study on features and logging evaluation of deep coal reservoir inNorth Shizhuang Block of Qinshui Basin

Based on the logging method, an explanation and evaluation were conducted on the roof and floor physical properties, coal structure; porosity and permeability of the deep coal reservoir.A study was conducted on the rock mechanics features, gas content features and geostress distribution law of the deep coal reservoir.The evaluation results showed that in North Shizhuang of Qinshui Basin, the roof physical properties and sealing of No.3 seam were better than No.15 seam.The permeability of No.3 seam was better than the permeability of No.15 seam in Taiyuan Formation.In the west part of the study area, the depth of No.3 seam was deep and the thickness of No.3 seam was thin.In west part of the study area, the depth of No.15 seam was deep and the thickness of No.15 seam was high.The geostress logging explanation showed that in the south-west part of the study area, the geostress value of No.3 seam was max, the anisotropy of No.3 seam was strong and there was a big difference between the max geostress and the min geostress.In the south-west part of the study area, the geostress value of No.15 seam was max, the anisotropy in the north-west part of the study area was strong, the difference of the geostresses was high and the cracks were developed.Finally, an analysis was conducted on the reservoir features of the deep coalbed methane and the variation law of the deep geostress and the proposals were provided on the development and improvement of the logging explanation.