中低成熟阶段页岩有机质孔预测模型探讨  

Prediction models of organic pores in shale with low to moderate maturity

作　　者：郭秋麟[1] 武娜[1] 任洪佳[1] 陈宁生[1] 谌卓恒 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]加拿大自然资源部加拿大地质调查局

出　　处：《岩性油气藏》2017年第6期1-7,共7页Lithologic Reservoirs

基　　金：国家重点基础研究发展(973计划)项目"中国陆相致密油(页岩油)形成机理与富集规律"(编号:2014CB239000);中国石油股份公司科技项目"大中型岩性地层油气藏富集规律与关键技术"(编号:2016B-0301)联合资助

摘　　要：为了研究中低成熟阶段页岩有机质孔与页岩油的关系,对页岩有机质孔成因机理进行了分析,建立了页岩有机质孔隙度定量预测的转化率和产烃率2种理论模型,这2种模型都能够较好地预测页岩有机质孔隙度的上限值。根据扫描电镜观察的面孔率,建立了中低成熟阶段页岩有机质孔隙度预测模型,该模型可以计算页岩有机质孔隙度的近似值。统计分析表明:中国湖相页岩有机质面孔率与Ro之间呈指数关系,在中低成熟阶段,面孔率增长较慢;北美海相页岩有机质面孔率与Ro之间呈对数关系,在中低成熟阶段,面孔率增长较快。最后探讨了中低成熟阶段与高成熟—过成熟阶段页岩有机质孔的区别,指出中国中低成熟阶段湖相页岩有机质孔不如北美海相页岩有机质孔发育。Quantitative prediction of organic pores in shale with low to moderate maturity is significant for shale oil resources assessment. Theoretical models of the conversion rate and hydrocarbon generation rate were established to predict the organic porosity of shale quantitatively based on genetic mechanism of organic pores in shale. Both models can efficiently predict the upper limit for organic porosity of shale. Moreover,the statistic model for prediction of organic porosity of shale with low to moderate maturity was built with surface porosity observed through scanning electron microscope,which can be used to calculate the approximation of the organic porosity. The statistical analysis reveals findings in two aspects. Firstly,for the lacustrine shale in China,the surface porosity has an exponential relationship with Ro,and it increases slowly at the stages of low to moderate maturity. Secondly,for the marine shale in North America,the surface porosity has a logarithmic relationship with Ro,and it increases rapidly at the stages of low to moderate maturity. In addition,differences of organic pores between shale with low to moderate maturity and shale with high to over maturity were discussed. It is indicated that the lacustrine shale with low to moderate maturity in China contains less organic pores than the marine shale in North America,which provides references for study on organic pores in shale and assessment and exploration of shale oil resources.

关 键 词：有机质孔 面孔率 页岩孔隙度 干酪根 页岩油 资源评价 

分 类 号：P631.4[天文地球—地质矿产勘探]