Abstract In this paper, systematic classification was conducted for the fissure systems of China's coal
seams, and the main causes for the different types of fissures were described. Based on 2D, 2C
anisotropic elastic waveequation staggering grid highorder finitedifference numerical
simulation, the authors carried out the numerical simulation of elastic wave field for the isotropy model
and the water-saturated and dry media 2D layered model with fracturebearing coal seams of high
fracturing density. The results show that, in comparison with the fracturesfree coalseam, the
fracturesbearing coalseam has the following characteristics: the surge impedance of the boundary
plane at the top and the bottom is changed due to the change of wave velocity, causing the change of
dynamic characteristics of the wave. The AVO phenomenon is especially obvious. The characteristics of
x component and z omponent are opposite in dry fractural media and in watersaturated
fractural media, and the velocity of wave is faster in watersaturated fractural media than in dry
fractural media. It is thus thought that coalseam fractures are detectable by using anisotropy theory.
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