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The use of geophysical techniques for exploration of coalbed methane (gas) is still in the exploratory stage. Strengthen basic research, and actively carry out ultrasound physics to achieve breakthroughs in key areas, and the formation of geophysical techniques for the geological conditions of China's coalbed methane exploration and development is a major research trends. Response relationship between the characteristics of lithology and physical properties of the test gas-rich and gas-rich coal seams, and their physical properties and well logs and seismic wave field is the the CBM petrophysical study of important content. The paper through the coal samples, laboratory temperature and pressure conditions of the coal core flexibility test and field test geophysical logging and statistical analysis to study the S-wave velocity characteristics of the coal, the attenuation characteristics azimuthal anisotropy characteristics of elastic modulus amount of coal rank elastic parameters; study of Coal (moisture, ash, volatile matter), the porosity, the relationship between the physical parameters of the geological parameters as gas content and coal density, speed, and resistivity and Ayutthaya mine, for example, well to seismic poststack joint inversion predicted the No. 3, No. 6 coal seam gas distribution. The following conclusions: (1) research and analysis drawn by six different ranks of coal elasticity test ① coal compressional wave velocity, shear velocity and apparent density are related, and along the coal seam inclined and vertical coal layers of management direction P-wave velocity gradually reduced; does not exist in the same relationship between the wave velocity in the strike, dip and vertical, performance regularity poor; compressional wave velocity and shear wave speed in the same direction of the coal and rock a good linear correlation exists, but at the same spread different direction of polarization direction shear wave speed and the same direction as the longitudinal wave speed linear relationship, there is a different direction shear velocity differences. ② coal and S-wave velocity, attenuation, Poisson's ratio minimum azimuthal anisotropy in the vertical direction of the bedding, parallel bedding direction. ③ maximum vitrinite reflectance and the apparent density of the coal in a positive correlation, and related negative Poisson's ratio, the elastic modulus is related, the wave velocity is related to the quality factor of a positive correlation, in which the highest degree of correlation of the quality factor. (2) obtained by logging test the gas content and the velocity, density, resistivity negative correlation; seam porosity and acoustic time, the neutron is related to the density negative; coal and rock moisture increases, the wave velocity increases, sub-reduced, the density increases, the natural gamma ray increases, resistivity decreases; coal rock ash increases, the density increases, natural gamma ray increases, the resistivity decreases, acoustic decreases; the coal rocks volatiles increases, increased density, increased natural gamma, resistivity increases, the wave velocity increases. (3) predict geological parameters through to establish coal seams physical parameters mathematical relationship model, and model validation, the error is small, the results are reliable.
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