煤岩参数测井解释方法——以韩城矿区为例

Logging interpretation of coal petrologic parameters: A case study of Hancheng mining area

鉴于煤岩各工业组分的密度、声波速度等物理参数无法通过实验直接测出,煤储集层测井解释精度低的问题,以韩城矿区为例,探索煤岩参数测井解释方法。通过对韩城矿区大量煤样的工业组分含量、孔隙度、含气量以及密度和声波速度等参数的实验测定,采用枚举法标定出了上述参数值。在煤岩各工业组分含量与煤岩密度、声波速度关系研究基础上,通过数值拟合研究了各工业组分含量与补偿密度、声波时差测井响应的关系,即随着固定碳含量增加、灰分含量降低,煤层测井密度值降低,声波时差值增大。将统计分析法与理论模型法相结合,建立了煤储集层工业组分含量、含气量、孔隙度解释模型,进而编制了煤储集层测井综合解释软件,实际应用效果良好。

Aiming at a serious obstacle for building a logging interpretation model to accurately interpret density and sonic speed value of each coal component which cannot be measured directly in lab scale, a logging interpretation method of coal reservoir parameters was studied using the Hancheng mining area as an example. The enumeration method was used to calculate density and sonic speed value of fixed carbon, ash, and volatile according to experimental determination of industrial components, pore, gas content, density and sonic speed value of many coal samples in the Hancheng mining area. On the basis of the relationships of each coal component and its density and sonic speed value, logging response relationships between each component and its compensated density and acoustic travel-time differences were studied using numerical fitting. As fitted carbon content increases, ash content and density decrease and sonic speed difference increase. By combining statistical analysis method and theory model calculation method, interpretation models of industrial components, gas content and pore for coal reservoirs were built and a logging integrated interpretation software was programmed, which have got good effect in actual application.