Geostress prediction and comprehensive evaluation based on logging information in coalbed methane block

In order to analyze the cross section and plane distribution features of geostress in A Coalbed Methane Block, a prediction model was established based on the logging information.According to the relativity between the geostress and the permeability, the plane difference of the permeability was studied. The results showed that in the central part of A Block, the depth of No. 3 seam was moderate and the min horizontal principal stress was below 12 MPa. The geostress condition of the coal reservoir mainly was σv >σH>σh. When the seam depth was between 740～1 100 m, the min horizontal principal stress was 12～22 MPa and the geostress condition of the coal reservoir was σH ≥σv. When the lateral pressure coefficient was less than 1.0 in the area, the seam depth was shallow, the vertical principal stress was in a leading position and the well location ratio with an average gas production over 500 m3/d would be taken 64.2%. The permeability would be in an index reclined tendency with the min horizontal principal stress increased. A max value of the permeability in the central part of the Block could be over 0.2×10-3μm2 and the average gas production was relatively high.