罗家地区沙三段页岩油生成与赋存的模拟实验研究

发布时间：2018-06-07 02:20

本文选题：页岩油 + 滞留烃　；参考：《中国石油大学(华东)》2015年硕士论文

【摘要】：沾化凹陷沙三段优质烃源岩分布广、厚度大,演化程度处于生油高峰期,具备形成泥页岩油气的物质基础。本文选取沾化凹陷沙三下亚段块状、层状和纹层状等代表性烃源岩样品进行主要生油期的生排烃模拟实验,结合荧光薄片和环境扫描电镜分析,探讨不同岩性烃源岩生排烃效率差别,排出油及滞留液态烃数量和组成差异以及滞留液态烃储集空间及赋存,对页岩油形成和赋存进行初步评价。通过生排烃模拟实验及荧光薄片和环境扫描电镜观察发现不同岩性烃源岩生排烃过程,排出及滞留液态烃组成以及滞留液态烃储集和赋存均存在一定差别。三种不同类型烃源岩生油率,滞留烃及排出油产率均随模拟温度升高呈现先增大后减小的趋势。纹层状烃源岩Ro范围在0.7%~1.0%之间滞留烃产率明显大于排出油,滞留率/排出率最大达5.37(Ro=0.8%);在生油早期阶段分馏现象明显,排出油较滞留烃含有更多的轻质组分;层间微裂缝是滞留液态烃主要储集空间,宽度随成熟度增大而增大,此外方解石晶间孔缝及石英、黄铁矿、粘土矿物晶间孔内也赋存一定量液态烃。层状烃源岩Ro范围在0.7%~0.9%之间滞留烃产率明显大于排出油,滞留率/排出率值在Ro为0.7%时最高;生油早期阶段排出油含有较多轻质组分,但分馏现象较纹层状烃源岩不明显;滞留液态烃主要赋存在方解石边缘裂缝,黄铁矿、白云石晶间及粘土矿物孔隙中,作为储集空间的裂缝形成作用非常明显。块状烃源岩仅在Ro为0.7%时滞留烃产率大于排出油产率;排出油和滞留烃组成差异不大;随演化程度增强,岩石出现裂缝,滞留液态烃主要赋存于与生烃相关的裂缝中,其它液态烃零星分散在粘土矿物孔隙中。根据不同类型烃源岩生烃过程,结合沾化凹陷罗家地区沙三下亚段有机质演化剖面,认为块状、层状和纹层状页岩油勘探的最有利成熟度范围分别为0.7%~0.9%,0.7%~1.0%,0.8%~1.1%,对应的深度段分别为3300~3600m、3300~3800m、3600-4000m。但块状烃源岩由于有机碳含量和富集度低,并不十分有利于页岩油形成。
[Abstract]:The high quality source rocks of the third member of Shahejie formation in Zhanhua depression are widely distributed, thick, and the evolution degree is in the peak of oil generation, which has the material foundation to form shale oil and gas. In this paper, the typical source rock samples, such as block, stratiform and laminar layers, are selected to simulate hydrocarbon generation and expulsion in the main oil generation periods in Zhanhua sag, combined with fluorescence flake and environmental scanning electron microscope analysis. This paper discusses the difference of hydrocarbon generation and expulsion efficiency of different lithologic source rocks, the difference of quantity and composition of discharged oil and retained liquid hydrocarbon, and the storage space and occurrence of retained liquid hydrocarbon, and makes a preliminary evaluation on the formation and occurrence of shale oil. Through hydrocarbon generation and expulsion simulation experiment, fluorescence thin slice and environmental scanning electron microscope, it is found that there are some differences in hydrocarbon generation and expulsion process, expulsion and liquid hydrocarbon composition, reservoir and occurrence of retained liquid hydrocarbon in different lithologic source rocks. The oil generation rate, residual hydrocarbon yield and oil output rate of three different types of source rocks increased first and then decreased with the increase of simulated temperature. In the range of 0. 7% ~ 1. 0% of laminated source rock, the yield of retained hydrocarbon is obviously higher than that of oil, and the maximum retention rate / discharge rate is 5. 37 ~ 0. 8%, the fractionation phenomenon is obvious in the early stage of oil generation, and the expelled oil contains more light components than the remaining hydrocarbon. Interlayer microfracture is the main reservoir space of liquid hydrocarbon, and the width increases with maturity. In addition, there are some liquid hydrocarbon in intergranular pore of calcite and quartz, pyrite and clay mineral. In the range of 0. 7 ~ 0. 9% of stratiform source rocks, the yield of retained hydrocarbon is obviously larger than that of the expelled oil, and the value of retention rate / discharge rate is the highest when Ro is 0. 7, the oil discharged in the early stage of oil generation contains more light components, but the fractionation phenomenon is less obvious than that of laminated source rocks. The residual liquid hydrocarbon mainly occurs in the edge fractures of calcite, pyrite, dolomite intergranular and clay mineral pores. The residual hydrocarbon yield of block source rock is only greater than that of expelled oil when Ro is 0.7, and the difference between expelled oil and residual hydrocarbon composition is not obvious. With the increase of evolution degree, cracks appear in the rock, and the residual liquid hydrocarbon mainly occurs in the fractures related to hydrocarbon generation. Other liquid hydrocarbons are scattered in the pores of clay minerals. According to the hydrocarbon generation process of different types of hydrocarbon source rocks, combined with the evolution profile of organic matter in the lower member of Sha3 in Luojia area, Zhanhua Sag, it is concluded that the most favorable maturity range for exploration of massive, stratified and laminated shale oil is 0.70.0.0.0.0.0.10 and 0.80.1.1and the corresponding depth is 33003600m33003800mt ~ 3600-4000m. However, block source rocks are not very favorable for shale oil formation because of their low organic carbon content and enrichment.
【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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