东濮凹陷杜桥白地区天然气藏的成藏期次

FORMATION STAGES OF NATURAL GAS RESERVOIRS IN DUQIAOBAI AREA OF DONGPU DEPRESSION

任战利 冯建辉 崔军平 任来义

Ren Zhanli Feng Jianhui Cui Junping Ren Laiyi

储层自生伊利石同位素年龄、油气藏饱和压力及流体包裹体均一温度等的测试结果表明:东濮凹陷杜桥白地区天然气成藏主要分为两大阶段。第一阶段大约在30.4～18.4Ma间,相当于东营馆陶组沉积早期,是天然气藏最为主要的形成时期。此阶段大部分对应于27～17Ma的剥蚀期,因地层剥蚀压力减小,有利于天然气成藏。第二阶段为2Ma以来(相当于第四纪)。这一阶段一方面是已形成气藏的调整,另一方面是二次生成天然气的继续注入。杜桥白地区天然气藏形成期总体上具有层位越新、成藏时期越晚,层位越老、成藏时期越早的特点。相比而言,杜寨地区天然气成藏较早,桥口白庙地区成藏相对较晚。

The results of isotope dating of illite in hydrocarbon reservoirs and testing results of saturation pressure and homogenization temperature of fluid inclusion indicate that natural gas reservoirs in Duoqiaobai area of Dongpu depression can be mainly divided into two mega-stages;The first stage is about 30.4-18.4Ma corresponding to the early sedimentary stage of Dongying-Guantao Formation, the chief formation stage of natural gas reservoirs. The most of this stage is in correspondence with the erosion stage of 27-17Ma which is favorable for the formation of natural gas reservoirs due to the reduction of erosion stratum pressure. The second stage is equivalent to the Quaternary(since 2Ma),this stage is on one hand for adjustment of the formed natural gas reservoirs, on the other hand for continuously injection of the secondary crop gas. The characteristics of formation of natural gas reservoirs in Duqiaobai area of Dongpu depression is in general with the newer of layer, the later of gas reservoirs forming and the older of layer, the earlier of gas reservoirs forming. The formation stage of natural gas reservoirs in Duqiaobai area is earlier in comparison with that in Qiaokou and Baimiao area.

10.11743/ogg20020416