吉木萨尔凹陷二叠系芦草沟组细粒沉积岩层理沉积构造类型、组合特征及储集意义  

Bedding structure types,combinations and reservoir significances of fine-grained rocks of the Permian Lucaogou Formation in Jimsar Sag,Junggar Basin

作　　者：何吉祥 陈轩[2] 李映艳[1] 赵秋霞 刘函汐 彭宇[1] 李英菊 尹太举[2] HE Jixiang;CHEN Xuan;LI Yingyan;ZHAO Qiuxia;LIU Hanxi;PENG Yu;LI Yingju;YIN Taiju(Research Institute of Exploration and Development,PetroChina Xinjiang Oilfield Company,Karamay 834000,China;Geoscience School of Yangtze University,Wuhan 430100,China;PetroChina Liaohe Oilfield Company,Panjin 124010,China)

机构地区：[1]中国石油新疆油田分公司勘探开发研究院,克拉玛依834000 [2]长江大学地球科学学院,武汉430100 [3]中国石油辽河油田公司,盘锦124010

出　　处：《海洋地质与第四纪地质》2025年第1期178-187,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金“吉木萨尔凹陷芦草沟组页岩油甜点沉积动力过程模拟”(4207119);中国石油股份重大科技专项“陆相中高成熟度页岩油勘探开发关键技术研究与应用”(2019E-26,2019E-26-07,2019E-26-08);中石油集团重大科技专项“吉木萨尔页岩油国家级示范区水平井效益开发关键工程技术集成与试验”(2020F-50)。

摘　　要：细粒沉积岩中的层理是影响页岩储层物性的关键因素。吉木萨尔凹陷二叠系芦草沟组发育丰富的层理构造。基于工区内钻井、岩芯、薄片及物性资料,开展了层理构造特征、成因及储集意义分析。本文将1 cm厚度作为界限,小于1 cm的沉积层称为纹层,大于1 cm沉积层称为层理。研究表明:纹层与层理在形成沉积水动力条件及厚度规模上存在差异,识别出两类层理组合,第一类为厚层的层理-纹层组合,主要见于粉细砂岩中,垂向上依次发育对偶粒序层理、块状层理、交错层理、爬升波纹层理及不规则纹层,反映异重流水道成因;第二类为薄纹层为主的组合,通常见于泥质粉砂岩,垂向上为对偶粒序层理与不规则纹层,反映出异重流朵叶体成因特征。第一类组合指示了强水动力条件,如异重流水道,其单层厚度及累计厚度大,储集性好;第二类组合指示较弱水动力条件,如异重流朵叶体,其单层厚度及累计厚度较小,储集性相对较差。该研究可以为细粒沉积学及页岩油勘探开发实践提供有价值的参考。The lamination and bedding structures in fine-grained rocks are key factors affecting the quality of shale oil reservoir.The Permian Lucaogou Formation in the Jimsar Sag,Junggar Basin,NW China was studied for this.Based on drilling wells,cores,thin sections,and physical property data of the area,the characteristics,genesis,and reservoir significance of bedding structures were analyzed.Thickness of 1cm was defined as the boundary:less than 1cm referred to a lamina,and greater than 1 cm referred to a bedding.Results show that,both laminae and beddings are in sedimentary origin,showing differences in hydrodynamic condition and thickness.Two types were identified.The first one is thick-bedded bedding-lamination type,often shown in fine-grained sandstone,with vertical development of upward-coarsening/finning bedding,massive bedding,cross bedding,climbing ripple bedding,and irregular lamination,indicating the strong hydrodynamic origin such as hyperpycnal channels.The second type is laminae-dominated one usually seen in muddy siltstone,consisting of vertical upwardcoarsening/finning bedding and irregular lamination,which is formed in hyperpycnal lobe indicative of week hydrodynamic origin.The first type generated large single-layer thickness and cumulative thickness,and good reservoir properties,the second type resulted in smaller single-layer thickness and cumulative thickness,and relatively poor reservoir properties.This understanding provides valuable references for study in sedimentology of fine-grained rocks,and for shale oil exploration and development practices.

关 键 词：沉积构造 层理 纹层 异重流 页岩油 芦草沟组 

分 类 号：P536[天文地球—古生物学与地层学]