石油实验地质2025，Vol.47Issue(3)：606-620,15.DOI:10.11781/sysydz2025030606
准噶尔盆地吉木萨尔凹陷二叠系芦草沟组不同岩相泥质烃源岩品质与含油性特征
Quality and oil-bearing properties of argillaceous hydrocarbon source rocks across different lithofacies of Permian Lucaogou Formation in Jimsar Sag,Junggar Basin:
摘要
Abstract
The study on the quality and oil-bearing properties of argillaceous hydrocarbon source rocks across different lithofacies is crucial for understanding shale oil enrichment patterns and predicting sweet spots.57 mudstone samples from the Permian Lucaogou Formation in the well J10025 of the Jimsar Sag,Junggar Basin were selected in this study.Based on lithofacies classification,the quality and oil-bearing properties of those argillaceous hydrocarbon source rocks across different lithofacies were systematically investigated through X-ray diffraction(XRD),thin-section observation,rock pyrolysis,organic petrology,vitrinite reflectance(Ro)measurement,and multi-temperature pyrolysis.The results indicated that 7 lithofacies were predominantly developed in the Lucaogou Formation of the Jimsar Sag,including massive felsic mudstones,massive calcareous mudstones,massive dolomitic mudstones,laminated felsic mudstones,laminated calcareous-bearing mudstones,laminated calcareous mudstones,and laminated dolomitic mudstones.Distinct quality differences were observed in those source rocks.The massive felsic mudstones and massive calcareous mudstones exhibited poor quality,while massive dolomitic mudstones were moderate-quality source rocks.The laminated felsic mudstones demonstrated good quality,whereas laminated calcareous-bearing mudstones,laminated calcareous mudstones,and laminated dolomitic mudstones were high-quality hydrocarbon source rocks.The massive dolomitic mudstones exhibited relatively favorable oil-bearing capacity and mobility,making them potential sweet spot lithofacies.In the well J10025,mudstones with relatively good oil-bearing properties were deposited at depth intervals of approximately 3 500 to 3 570 m and 3 700 to 3 750 m.However,its overall poor mobility restricted the development of the mudstone-type shale oil sweet spots.The main factors influencing the oil-bearing capacity and mobility of mudstones included hydrocarbon-generating capacity,hydrocarbon expulsion efficiency,and total organic carbon(TOC)content.The content of free hydro-carbons was significantly controlled by the hydrocarbon-generating capacity of mudstones.Meanwhile,the wide-spread efficient hydrocarbon expulsion in mudstones directly led to a reduction of free oil content.Additionally,high TOC content resulted in a large amount of adsorbed oil,which constrained shale oil mobility.关键词
页岩油/岩相/烃源岩品质/含油性/芦草沟组/吉木萨尔凹陷/准噶尔盆地Key words
shale oil/lithofacies/hydrocarbon source rock quality/oil-bearing properties/Lucaogou Forma-tion/Jimsar Sag/Junggar Basin分类
石油、天然气工程引用本文复制引用
何晋译,冷筠滢,何文军,李志明,刘得光,杨森,李楚雄..准噶尔盆地吉木萨尔凹陷二叠系芦草沟组不同岩相泥质烃源岩品质与含油性特征[J].石油实验地质,2025,47(3):606-620,15.基金项目
国家自然科学基金(42090022)和中国石化石油勘探开发研究院院重点课题(YK-2023-18)联合资助. （42090022）
