超压和富氢背景下镜质组反射率计算模型——以渤海湾盆地渤中西次凹东三段烃源岩为例

Vitrinite reflectance modeling under overpressure retardation and hydrogen suppression:A case study of source rocks from the third member of Dongying Formation, West Bozhong Sub-depression,Bohai Bay Basin

胡安文 李慧勇 江涛 许鹏 史盼盼

Hu Anwen Li Huiyong Jiang Tao Xu Peng Shi Panpan

中海石油(中国)有限公司天津分公司 渤海石油研究院, 天津 300452

Bohai Oil Research Institute, Tianjin Branch of CNOOC Limited, Tianjin 300452, China

在考虑富氢和超压对镜质组反射率的抑制作用下，对传统仅考虑了温度和时间的镜质组反射率计算模型——Easy%Ro模型进行了重新校正。通过引进富氢校正系数和超压抑制系数，建立起适合双重抑制背景下镜质组反射率计算模型，并利用渤海湾盆地渤中西次凹受双重抑制作用和未受双重抑制作用影响的镜质组反射率Ro实测资料，确定了相关参数。模拟结果表明，在双重抑制作用影响的地层中，镜质组反射率Ro的模拟值与实测值吻合较好，但与Easy%Ro模型的计算结果相差悬殊，双重抑制作用对Ro的影响可达0.2%~0.4%。超压抑制了有机质热演化，导致生烃门限下移和生烃时间延迟，这非常有利于油气晚期成藏。

The Easy%Romodel,in which only temperature and time were considered,was calibrated to take into consideration the suppression of vitrinite reflectance by hydrogen-rich organic matter and overpressure.A new model was developed by introducing a hydrogen-rich correction coefficient and overpressure inhibiting coefficient.Using the data collected from both the double-suppressed wells and the normal wells in the West Bozhong Sub-depression of Bohai Bay Basin,China, some relative parameters were determined and the model was tested.The results show that the computed vitrinite reflectance values in double-suppressed formation agree with the mea-sured data,but are significantly different from those predicted by the Easy%Romodel.And the vitrinite reflectance values were reduced by 0.2%~0.4% in double-suppressed formations. Organic matter maturation was retarded by overpressure.It led to the increase of depths of the hydrocarbon generation threshold and the delay of time of hydrocarbon generation,which was advantageous for late hydrocarbon accumulation.

国家重大专项“渤海海域大中型油气田地质特征”（2011ZX05023-006-002）和国家自然科学基金项目（U1262106，41572135）资助。

https://doi.org/10.11781/sysydz201701106