摘要
页岩油是赋存于富有机质页岩层系中的石油,勘探开发潜力巨大。页岩油赋存状态多样,油相主要以游离态赋存于无机矿物孔隙和有机质内部发育的孔隙中,以及以溶解态存在于有机质高分子缩聚物内部的溶解态油相,准确劈分不同赋存状态的油相体积对页岩油藏储量精细评价具有重要意义。目前,页岩油储层含油量主要是在孔径分析法、流体饱和实验、热解法或氯仿沥青“A”法等实验测试的基础上计算得到,但受限于测试原理和条件,这些方法无法准确表征不同赋存态页岩油体积。现基于页岩储集特征和流体赋存状态分析,建立页岩油藏各赋存态油相体积的理论计算模型,模型能够根据页岩物性参数定量计算页岩无机孔隙中的游离态油相体积、有机孔隙中的游离态油相体积、有机质内部的溶解态油相体积和总含油量,并能够得到页岩无机矿物介质和有机质的非常规物性参数,实现页岩各赋存态油相体积和总含油量的准确计算。结果表明:总有机碳含量主要影响有机质内部的有机游离态油相体积与溶解态油相体积,有机质溶解度主要对溶解态油相体积产生影响,页岩总孔隙度主要受无机孔隙度的影响,对于总孔隙度较高的页岩,其内部的无机游离态油相含量越高,有利于弹性开采。研究成果为页岩油藏的储层表征和储量准确评价提供了理论依据。
Shale oil exists in organic-rich shale formations and exhibits tremendous potential for exploration and development.Shale oil exists in various occurrence states,oil phase predominantly exists in the free states within the pores of inorganic minerals and organic matter,and in the dissolved states within the condensation polymers of organic matter.Accurate delineation of the oil volume in various occurrence states is significant for the detailed reserve evaluation of shale oil reservoir.At present,the shale oil reserve is mainly evaluated on the basis of experimental tests,such as pore size analysis,vacuum-imbibition method,rock pyrolysis method or chloroform asphalt“A”method.However,due to the limitation of testing principles and conditions,these methods can not accurately characterize the volume of shale oil in different occurrence states.Based on the analysis of shale reservoir characteristics and fluid occurrence states,a theoretical model was established to calculate the volume of shale oil in various occurrence states.The model can accurately calculate the free-phase oil volumes in shale inorganic pores and organic pores,the dissolved-phase oil volume within organic matter,and total oil volume.Furthermore,it can determine the unconventional physical parameters of shale inorganic minerals and organic matter.The results show that the total organic carbon content primarily affects the volume of free-state oil in organic pores and dissolved-state oil,while the solubility of organic matter mainly impacts the volume of dissolved-state oil.The total porosity is chiefly influenced by inorganic porosity,the oil volume in inorganic pores is higher for shale rock with greater porosity,which is favorable for elastic recovery.The research results provide a theoretical basis for reservoir characterization and accurate reserve evaluation of shale oil reservoirs.
作者
李亚军
庄春辉
吴忠宝
董明哲
桑茜
宫厚健
徐龙
LI Ya-jun;ZHUANG Chun-hui;WU Zhong-bao;DONG Ming-zhe;SANG Qian;GONG Hou-jian;XU Long(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China)
出处
《科学技术与工程》
北大核心
2024年第28期12105-12111,共7页
Science Technology and Engineering
基金
国家自然科学基金重大项目(42090024)。
关键词
页岩油
无机孔隙
有机孔隙
游离态
溶解态
储量
shale oil
inorganic pores
organic pores
free state
dissolved state
reserve
