东营凹陷沙四下亚段-孔店组储层流体包裹体特征及油气充注期次

 东营凹陷深层的沙四下亚段-孔店组是该区油气勘探的接替层系,以沙四下亚段-孔店组储层流体包裹体为研究对象,通过包裹体显微荧光观察和均一化温度测试,结合埋藏史和热史模拟,分析了研究区油气充注特征。研究结果表明,东营凹陷南坡沙四下亚段-孔店组储层经历过1 期油气充注,发生于明化镇组沉积期至现今;而北坡经历过3 期油气充注,分别发生于沙三段沉积期、馆陶组沉积期和明化镇组沉积期至今;南坡沙四下亚段-孔店组油源来自于上覆的沙三下和沙四上亚段烃源岩,北坡比南坡埋深更大,且有沙四下亚段烃源岩的贡献;不同的地质背景、油气来源及生储配置关系,导致东营凹陷南、北坡沙四下亚段-孔店组油气充注期次的显著差异。

Fluid Inclusion Characteristics and Hydrocarbon Charging Stages of the Lower Section of 4th Member of Shahejie Formation and Kongdian Formation in the Dongying Depression

The lower section of the 4th member of the Shahejie formation and Kongdian formation (Es₄^x-Ek) in the deeper Dongying depression are supersedure strata of oil and gas exploration. Based on the observation of microscopic fluorescence and homogenization temperature test of fluid inclusions and in combination with the simulation of burial and thermal history, the hydrocarbon charging characteristics of Es₄^x-Ek reservoirs are analyzed. The result shows that Es₄^x-Ek reservoirs in the south slope of Dongying depression experienced one stage of hydrocarbon charging, which is from the Minghuazhen to the present day. However, the Es₄^x-Ek reservoirs in the north slope experienced three stages of hydrocarbon charging, which are the 3rd member of Shahejie period, Guantao period, and Minghuazhen to the present day. The burial depth of the north slope is deeper than that of the south slope. The oil source of Es₄^x-Ek reservoirs in the south slope is overlying Es₃^x and Es₄^x source rocks, whereas the oil source of the north slope contains Es₄^x source rock. The different geological backgrounds, oil sources, and source-reservoir combination patterns lead to the significant differences of hydrocarbon charging characteristics between the south and the north slopes.