基于煤岩波速比及抗剪强度的煤体结构区分

Coal structure differentiation based on coal-rock velocity ratio and shearing strength

煤层气储层煤体结构类型对储层产能影响巨大。煤岩波速比反映原生结构煤与碎裂结构煤的各向异性差异;抗剪强度反映不同结构煤岩的力学特性差异。利用阵列声波测井资料,提取煤岩纵横比及抗剪强度,通过统计分析,划分了原生结构煤与碎裂结构煤的优势区间,形成了波速比及抗剪强度联合判识煤体结构的划分标准,准确率在84%左右。该方法为煤体结构划分提供一定理论依据。

The type of coalbed gas in the coalbed methane reservoir has a great impact on the productivity of the reservoir.The wave velocity ratio of coal and rock reflects the anisotropy difference between primary structure coal and fragmented structure coal;the shear strength reflects the difference in mechanical properties of coal and rock with different structures.The array acoustic logging data was used to extract the coal rock aspect ratio and shearing strength.Through statistical analysis,the dominant regions of primary structure coal and fragmentary structure coal were divided.The classification standard for identifying the coal body structure by combining the wave velocity ratio and shearing strength has been formed and the accuracy rate is about 84%.This method provides a certain theoretical basis for the division of coal structure.