【作者】 张宇；

【导师】 闫涛滔； 张绍韡；

【作者基本信息】 太原理工大学 ， 资源与环境（专业学位）， 2023， 硕士

【摘要】 鄂尔多斯盆地东缘上古生界石炭-二叠系发育多套海陆过渡相煤系烃源岩,是区域煤系气勘探开发的重点层位。本论文以鄂尔多斯盆地东缘山西临汾大宁-吉县区块上古生界石炭-二叠系煤系地层为研究对象,结合录井资料,采用总有机碳含量（TOC）、岩石热解（Rock-Eval）、傅里叶变换红外光谱（FTIR）、固体碳核磁(¹³C-NMR)、X射线衍射（XRD）、低场核磁共振（Low field NMR）等实验测试手段,分析了研究区上古生界煤系烃源岩的油气地球化学特征、官能团微观结构特征、岩石学特征和孔隙性特征,建立综合评价体系,进行研究区煤系烃源岩分布优势层位优选,为区域煤系气勘探开发提供有效依据。论文研究主要取得的认识和成果如下:（1）开展了煤系烃源岩地球化学特征分析。研究区煤系烃源岩TOC平均值为2.22%,碳质泥岩TOC平均值为12.03%,煤岩TOC平均值为60.05%,总体达到中等-好烃源岩级别。烃源岩有机质类型以III型干酪根为主,包含部分Ⅱ₂型干酪根。R_o介于2.02～2.78%之间,热演化程度较高,普遍达到过成熟阶段。（2）揭示了煤系烃源岩的官能团微观结构特征。采用FTIR和¹³C-NMR实验测试技术,解剖煤系烃源岩样品的FTIR结构参数和¹³C-NMR结构参数。结果表明,研究区煤系烃源岩的芳香结构参数、缩合程度结构参数及含氧官能团结构参数与有机质热演化程度成正相关关系,而脂肪结构参数和生烃潜力结构参数与热演化程度成负相关关系。（3）剖析了煤系烃源岩内部结构特征。基于XRD和Low field NMR实验开展煤系烃源岩层内部矿物及孔裂隙发育特征研究。结果表明,研究区煤系烃源岩样品的矿物组成特征均以石英和粘土矿物为主,其他矿物含量较低;脆性指数整体较高,有利于压裂开采。泥页岩层内部孔隙总体上以大孔为主,中孔为辅,中大孔之间连通性较好,有利于形成较高的页岩气产能保障。（4）建立了研究区煤系烃源岩多层次模糊综合评价体系。基于煤系烃源岩层地球化学特征、储层微观结构特征及储层内部特征研究结果,优选了研究区煤系烃源岩储层评价指标,确定了优势层位评价参数、权重值及其定量化评价模型,最终建立多层次模糊综合评价体系,进行了煤系烃源岩优势层位的划分及优选。更多还原

【Abstract】 There are several sets of transitional facies coal measure source rocks developed during the Upper Paleozoic Carboniferous and Permian,in the eastern margin of Ordos Basin,which are the main targets of the exploration and development for coal measure gas in this area.In this paper,the geochemical characteristics,functional group microstructure characteristics,petrological characteristics and porosity developmental characteristics of the upper Paleozoic coal measure source rocks in the study area were analyzed based onthe foundmental geological and engineering parameters,combined with experimental tests(i.e.total organic carbon content（TOC）,Rock pyrolysis（Rock-eval）,Fourier transform infrared spectroscopy（FTIR）,solid carbon nuclear magnetism(¹³C-NMR),X-ray diffraction（XRD）,low field nuclear magnetic resonance（Low field NMR）,etc.),Then,a comprehensive evaluation system was established to optimize the distribution of favorable strata of the coal measure source rocks in the study area,so as to play a guiding role in the exploration and development of coal measure gas.The main understandings and achievements of this research are as follows:（1）The geochemical characteristics of coal measure source rocks are analyzed.The average value of TOC for coal measure shale,carbon mudstone and coal rock is 2.22%,12.03%and 60.05%,respectively,which are all reaching the level of medium-good rank.The types of source rocks organic matter are mainly type III and part of type II.The vitrinite reflectance（Ro）of organic matter ranges from 2.02 to 2.78%,with a high thermal evolution degree,which are generally entered over-maturation phase.（2）The functional group microstructure characteristics of coal measure source rocks were revealed.FTIR and ¹³C-NMR were used to analyze the structural parameters of coal measure source rock samples.The results show that the aromatic structure parameters,condensation degree structure parameters and oxygen-containing functional group structure parameters of coal measure source rocks in the study area are positively correlated with the degree of thermal evolution of organic matter,while the fat structure parameters and hydrocarbon generation potential structure parameters are negatively correlated with the degree of thermal evolution of organic matter.（3）The internal characteristics of coal measure source rock are analyzed.The characteristics of mineral,pore and fissure development in coal measure source rock were studied based on XRD and NMR experiments.The results show that the mineral composition characteristics of coal measure source rocks in the study area are mainly quartz and clay minerals,while the content of other minerals are low.The brittleness indexes of coal measure source rocks are relative high,which is conducive for the fracturing operation.The internal pores of shale rock are dominated by large pores,supplemented by medium pores.The connectivity between large and medium pores is well,which is conducive for a higher shale gas production guarantee.（4）A multi-level fuzzy comprehensive evaluation system of coal measure source rocks is established.Based on the research results of geochemical characteristics of coal measure source rock,reservoir microstructure characteristics and internal characteristics of coal measure source rock,the evaluation index of coal measure source rock is optimized,and the evaluation parameters,weight values and quantitative evaluation model of these parameters are determined.Finally,a multi-level fuzzy comprehensive evaluation system is established,and the favorable strata of coal measure source rock are optimized.更多还原