下生上储式与上生下储式油源断裂油气输导差异性

为了研究不同生储盖组合的油气分布特征及规律,以下生上储式和上生下储式2个组合样式为例,在剖析油气运聚成藏模式及输导通道的基础上,通过油气分布与油源断裂油气通道特征关系对比,对2种组合样式的油源断裂运移油气特征的差异性进行研究.结果表明,其油气输导差异性特征主要体现在3个方面:①油气输导平面分布范围的差异性.下生上储式油...

Difference in Oil and Gas Transport between Lower-Source and Upper-Reservoir and Upper-Source and Lower-Reservoir Oil Source Faults

In order to study the characteristics and regularity of hydrocarbon distribution of different source-reservoir-cap assemblages, two assemblages (lower-source and upper-reservoir model and upper-source and lower-reservoir model) were studied for the difference in oil and gas transport characteristics of oil source fault on the basis of the analysis on hydrocarbon migration and accumulation pattern and transport channels and the comparison on characteristics of hydrocarbon distribution and transport channels in oil source fault. The results showed that the characteristics of oil and gas transport were mainly different in the following three aspects. 1) Difference in the plane distribution range of oil and gas transport: the oil and gas were transported within the hydrocarbon expulsion zone of lower-source and upper-reservoir oil source faults, while the oil and gas in upper-source and lower-reservoir oil source faults were transported downwards only when the overpressure value of the source rock was greater than the minimum overpressure required for the downward transport of oil and gas. 2) Difference in the end point and maximum distance of oil and gas transport: The upward transport of oil and gas in the lower-source and upper-reservoir oil source faults was ended at the closed regional caprock, and the distance between the bottom of closed regional caprock and the top of source rock was the maximum distance of downward oil and gas transport of the oil source fault; the downward transport of oil and gas in the upper-source and lower-reservoir oil source faults was ended at the site where the transport power was equal to the resistance, and the distance between such site and the source rock bottom was the maximum distance of downward oil and gas transport of the oil source fault. 3) Difference in horizons for lateral layered sandbody migration in oil and gas transport: The horizon of lateral layered sandbody migration in oil and gas transport of lower-source and upper-reservoir oil source faults was at the layer with high sandstone thickness/ formation thickness ratio under the closed regional caprock; the horizon of lateral layered sandbody migration in downward oil and gas transport of lower-reservoir and upper-source oil source faults was at all sandbodies above the end of its downward transport of oil and gas. The results of the study can provide a theoretical basis for oil and gas exploration in different source-reservoir-cap assemblages.