压汞试验在评价细碎屑岩低渗透储层中的应用

本文是以东濮凹陷卫城、濮城、文留、桥口等几个油气田下第三系沙三~4—沙四段低渗透储层研究成果为例,说明压汞试验在粉砂-泥质储集岩的储集性能分析中的应用。这类储层的不均一性更似碳酸盐岩储层,次生微孔隙及层间微缝是主要储集空间和油气通道。由压汞试验结果看出,最好的储层多属近漫溢微相和浅水道微相,毛管压力曲线属类型Ⅰ,启动压力低,孔隙分布均匀、正偏态、分选性好,残余润湿相饱和度为10％。

APPLICATION OF MERCURY INJECTION EXPERIMENT TO APPRECIATING LOW PERMEABILITY RESERVOIR OF FINE CLASTIC ROCKS

This paper illustrated application of mercury injectionexperiment to the appreciation of silt-mudy reservoir property with theexample of the study on low permeability reservoir of the Eogene Sha-34 to Sha-4 members of Weicheng, Pucheng, Wenliu, Qiaokou and Baimiao gas-oil fields, Dongpu depression. This kind of reservoirs is almost as unhomogeneous as carbonate reservoirs, Secondary microporosity and interstratal microcracks serve as major reservoir spaces and paths for hydrocarbon migration. Mercury injecticn experiments show that most of the best reservoirs belong to proximal overflow and shallow-channel microfacies with type I of capillary pressure curves. These microfacies needed a low starting pressure of mercury injection and have uneven distribution of porosity which is in single kurtosis, positive deviation and is well sorted with 10% satuaration of remaining wettingphase.