摘要
随着全球页岩气等非常规油气勘探的不断加强,烃源岩排气效率的研究越来越受到关注。根据页岩或煤中实测或理论计算的含气量数据,以及在不同热演化阶段的生气量,探讨了不同母质类型烃源岩在不同热演化阶段的排气效率。煤系烃源岩和海相Ⅰ—Ⅱ1型烃源岩排气效率随着成熟度的增加,排气效率逐渐增加,但两者存在很大的差异,煤系烃源岩排气效率很高,在RO=1.0%时为75%,在RO=5.5%时高达90%以上,高排气效率表明,煤系烃源岩生成的天然气绝大部分都运移到了储层,成为常规天然气和致密砂岩气的主要气源。与煤系烃源岩相比,海相Ⅰ—Ⅱ1型烃源岩排气效率较低,大部分低于70%,低排气效率结果表明,在页岩体系中生成的天然气相当一部分仍滞留在烃源岩中,残留在页岩中的天然气为页岩气的富集提供了物质基础。
With increasing of unconventional gases exploration(such as shale gas),the gas relative expulsion efficiency of source rocks is becoming an interesting topic. Based on data of gas content gotten from porosity and adsorptivity in the laboratory measurement and the theorical calculation, the expulsion efficiency of gas from source rocks with different types of kerogen and maturities has been studied. With the increasing of the maturity, the expulsion efficiency is becoming larger gradually. But there are great differences existed between coal-measures and marine source rocks with type [ - H 1 kerogen. The expulsion efficiency of gas from the coal measures is very high and is up to 75% ,even more than 90% at the thermal maturity(R%) of 1.0%. The result shows that the gas from the coal measures was expulsed into the reservoir mostly and be came an important source of the large coal-derived gas field. Compared with the coal measures, the gas expulsion efficiency for marine source rocks with type Ⅰ-Ⅱ1 kerogen is relatively lower and is mostly less than 70%. The gas from the shale mostly retains in the source rocks and become the important source of shale gas resource.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2014年第1期45-52,共8页
Natural Gas Geoscience
基金
国家科技重大专项(编号:2011ZX05007-001)
中国石油科学研究与技术开发项目(编号:2011B-0601)联合资助
关键词
烃源岩
页岩气
生气量
含气量
排气效率
Source rock
Shale gas
Gas generation amount
Gas content
Gas expulsion efficiency