油气成藏期研究新进展

传统的成藏期分析是从生、储、盖、运、聚、保等参数的配置,根据圈闭形成史、烃源岩生烃史及露点压力法作出的。但基于中国多数含油气盆地隶属叠合盆地的特性,具有多烃源层、多期油气生成、多期成藏,多期破坏的特点,20世纪90年代后期,引进并运用了流体历史分析方法。借助油藏地球化学、流体包裹体、伊利石 K-Ar 测年、储层沥青和油气水界面追溯法等确定成藏期的新方法,实现了由传统的定性(定期)研究到定量或半定量研究的转变,可以较准确确定油气藏形成时间。同时,鉴于叠合盆地油气藏形成具有较大的复杂性,在成藏期研究工作中仍需要重视基础地质工作,传统方法(圈闭形成期、生烃史)是进行新技术应用的基础。地球化学技术方法与地质背景相结合,传统方法与新方法相结合,定性与定量方法相结合,是今后油气成藏期研究的发展方向。

New advancement in study of reservoiring period

The reservoiring period has traditionally been analyzed from the matching of source rock,reservoir rock, cap rock,migration,accumulation and preservation parameters,on the basis of trap formation history,hydrocarbon generating history of source rocks and dew point pressure method.Considering that most of the petroliferous basins in China are superimposed basins,which are characterized by multiple source rocks,multi-stage hydrocarbon genera- tion,accumulation and destruction,fluid history analysis method was introduced in late 1990s.Utilization of several new methods,such as reservoir geochemistry,fluid inclusion,illite K-Ar dating,reservoir bitumen and tracing of oil- gas-water contacts,has converted the traditional qualitative(period determining)study to quantitative or senti-quanti- tative study,thus the formation time of pools can be relatively accurately calculated.In view of the complexity of the formation of reservoirs in superimposed basins,attentions should still be paid to basic geologic studies.Traditional methods,such as trap formation period and hydrocarbon generating history,are the basis of application of new tech- nologies.Future trends of reservoiring period studies are combining geochemistry method with geologic setting study, traditional method with new methods,and qualitative method with quantitative method.