摘要:吐哈盆地是我国重要的含油气盆地之一，对于常规油气前人做了大量工作。然而对非常规页岩气的研究才刚刚起步。页岩气以吸附或游离的形式存在于泥页岩及其夹层中，而泥页岩的矿物组分研究为页岩气的吸附储存以及泥页岩的裂缝评价、渗流运移、压裂造缝等的研究提供了必要的基础。本文在野外露头及钻井岩心观察的基础上，通过显微薄片分析和 X-衍射分析，结合有机地化及镜质体反射率测试结果，对吐哈盆地周边二叠系8个剖面及两口取心井的暗色泥页岩样品进行了系统分析，结果表明：1）吐哈盆地二叠系暗色泥页岩分布广、厚度大、有机质丰度高；暗色泥页岩主要形成于微蒸发、微咸水的浅湖—半深湖—深湖环境，主要由粘土矿物和石英组成，粘土矿物主要为伊 /蒙混层、绿泥石和高岭石组合；2）暗色泥页岩矿物组合分布具有一定规律性，反映了盆内“多凸多凹，凸凹相间”的特点；粘土矿物组合反映了中二叠世晚期干旱—潮湿频繁交替的气候条件，且风化程度中等；3）暗色泥页岩总体处于中 ?晚成岩作用阶段，成熟度高，达到了成熟—高成熟阶段，有利于页岩气藏的形成；4）脆性矿物含量大于40%，有利于页岩气的压裂开发。
关键词: 暗色泥页岩/
矿物组合/
二叠系/
页岩气/
吐哈盆地
Abstract:Turpan-Harmi Basin is one of the important petroliferous basin in China. Lots of study ofconventional oil and gas about the basin have been done, while the study of unconventionalshale gas has just started. Shale gas occurs in the form of adsorption or dissociation in the shaleand its interlayers. The study of the mineral components of shale provides a necessaryfoundation for the adsorption and storage of shale gas, as well as the study of fractureevaluation, seepage migration and fracture formation of shale. Based on description of filedoutcrop and core, analysis of microscope thin-section and XRD, combined with the test result oforganic chemistry and vitrinite reflectance（Ro）, the systemic analysis of Permian dark shale ineight filed outcrop and two drilling core wells in Turpan?Harmi Basin have been done. It isproved that 1）Permian dark shale in Turpan-Harmi Basin distributed widely, have largethickness and abundance of organic matter. The dark shale is mainly formed in the shallowlake-semi-deep lake-deep lake environment with micro-evaporation and brackish water. Theshale is composed of clay minerals and Quartz, while clay minerals made of layer of illite/smectite, Chlorite and Kaolinite mainly. 2）The distribution of dark shale mineral combination have some regular, it reflect that the lake have the characteristics of more convex and concave,convex and concave interphase in the basin. The clay mineral assemblages reflect the climaticconditions of frequent alternations between dry and humid, and have a moderate degree ofweathering. 3）The dark shale is in the middle-late stage of diagenesis and shows high maturityand over-high maturity, which is good for the formation of Shale gas reservoirs. 4）More than 40% Brittle mineral content is beneficial to the fracturing exploitation of shale gas.
Key words:Dark shale/
Minerals combination/
Permian/
Shale gas/
Turpan-Harmi Basin
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