基于地震沉积方法的煤系岩性及其沉积演化特征分析

为了清晰地揭示潘庄地区山西组主采3号煤层顶底板岩性及其沉积演化特征，基于地震沉积方法，建立了高分辨率等时地层格架，利用地层切片技术提取及优选敏感地震属性组合，并通过井点不同层序内岩性及沉积信息与地震属性实施层位配置关系进行敏感属性的标定，实现对山西组煤系地层成煤前后不同时期内岩性展布及其沉积演化特征的精细揭示。结果表明:山西组自下至上可划分为3个中期旋回，分别对应Sq₁₀、Sq₁₁和Sq₁₂三个四级层序；潘庄地区中期旋回可作为区域沉积研究的基本单元；最大波峰振幅、平均反射强度及均方根振幅可作为最优属性实施沉积岩性研究；山西组3号煤层聚煤前后岩性呈现渐变特征，砂质沉积逐渐增多，泥质沉积逐渐减少，总体呈现由下三角洲平原到上三角洲平原的缓慢过渡。

Analysis on lithology and sedimentary evolution characteristics of coal measures strata based on seismic sedimentation method

In order to clarify the lithology and sedimentary characteristics of the roof and floor of the No.3 coal seam in the Shanxi Formation of Panzhuang area，based on the seismic sedimentary method，the high-resolution isochronous strata were established.The sensitive seismic attribute combinations were extracted and optimized by stratal slicing technology.Then，according to the lithology and sedimentation information in different sequences of a single well，the horizon was configured with seismic attributes.In addition，the calibration of sensitive attribute combination was carried out，and different seismic attribute combinations were given geological and lithologic significance.Finally，it indirectly reveals the lithologic distribution and sedimentary space-time evolution characteristics in different historical periods before and after coal formation of coal measures in Shanxi Formation.Results have shown that:the Shanxi Formation can be divided into three middle-term cycles form bottom to top，corresponding to three four-level sequences:Sq₁₀，Sq₁₁ and Sq₁₂.The middle-term cycle in Panzhuang area can be used as the basic isochronous unit for the study of regional sedimentation.The maximum peak amplitude，average reflection intensity and root mean square amplitude can be used as the optimal attributes for sedimentary lithology research.The lithology of the No.3 coal seam before and after coal accumulation showed gradual characteristics，with sandy deposits gradually increasing and muddy deposits gradually less，which showing a slow transition from the lower delta plain to the upper delta plain.