烃源岩有限空间生排烃基础研究新进展

New progress in basic studies of hydrocarbon generation and expulsion of source rock in finite space

关德范 徐旭辉 李志明 郑伦举 马中良

Guan Defan Xu Xuhui Li Zhiming Zheng Lunju Ma Zhongliang

中国石油化工股份有限公司 石油勘探开发研究院, 北京, 100083 2. 中国石油化工股份有限公司 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡, 214151

SINOPEC Exploration & Production Research Institute, Beijing 100083, China 2. Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214151, China

利用DK-Ⅱ型地层孔隙热压生排烃模拟实验仪开展烃源岩有限空间生烃与压差排烃模拟实验研究,结果表明盆地持续沉降过程中烃源岩成烃过程明显显示3个阶段,其中成熟度小于0.70%之前,烃源岩处于缓慢生油阶段,0.70%～0.90%则处于快速生油阶段,至0.90%时已基本达到生油最高峰,大于0.90%之后,受烃源岩内部流体压力的作用,极大地抑制了烃源岩中干酪根向烃的转化;且在该阶段,烃源岩破裂作用排出油可滞留在烃源岩表面及与之有连通的微裂缝中,部分排出油可进入与烃源岩层互层的砂岩层内。烃源岩成熟度高于0.70%之后,当盆地整体抬升阶段烃源岩区与储集岩区压力系统差达到一个临界压力差值(约4～5MPa)时,才能使烃源岩生成的油较有效地发生远距离运聚并成藏。

Simulation of hydrocarbon generation and expulsion of source rock in finite space has been carried out with the hydrocarbon generation and expulsion simulation experimental instrument of type DK-Ⅱ with porosity,temperature and pressure under geological conditions.It has been concluded that the process of hydrocarbon generation of source rock during basin subsidence can be divided into 3 stages as follows.1)Ro≤0.70%,oil generates from source rock slowly;2)0.70% Ro 0.90%,oil generates rapidly,and reaches the peak when Ro is 0.90%;3)Ro 0.90%,oil gene-ration from kerogen has finished due to the fluid pressure in source rock.And during the 3rd stage,the oil expulsed from source rock cracking stays on rock surface and in connected microfractures.Part of the expulsed oil migrates into sandstones which interbed with source rocks.When the maturity of source rock is over 0.70% and the pressure differential between source rock and reservoir during basin uplifting reaches about 4-5 MPa,oil migrates far away and accumulates.

中国石油化工股份有限公司科技开发部项目(P08060)资助

https://doi.org/10.11781/sysydz201105441