A Multiscale Structural Analysis of Soft and Hard Coal Deposits in Deep High-Gas Coal Seams

Figure 1

Macroscopic structures of the soft and hard coal in the different coal seams. (a) Hard coal of the No. 4 coal seam. (b) Soft coal in the No. 4 coal seam. (c) Hard coal of the No. 13 coal seam. (d) Soft coal in the No. 13 coal seam.

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(b)

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