断裂带盖层油气封盖断接厚度下限的预测方法及其应用

在含油气盆地盖层未被断裂完全错开的条件下,采用断层岩石封闭能力与下伏储层岩石封闭能力比较的研究方法,建立一套盖层封闭油气所需断接厚度下限的预测方法,并将其应用于南堡凹陷南堡1号构造,研究馆三段火山岩盖层封闭下伏东一段油气所需断接厚度下限。结果表明:馆三段火山岩盖层在f1、f2、f3、f4断裂处封闭油气所需断接厚度均小于实际盖层的断接厚度,因此对下伏东一段储层中的油气均是封闭的,这与目前东一段油气分布有着较好的吻合关系;该方法用于研究盖层封闭油气所需断接厚度下限是可行的。

Prediction method and application of caprock faulted-contact thickness lower limit for oil-gas sealing in fault zone

Under the condition that caprock was not completely disconnected by fault in oil-gas bearing basins, a prediction method of caprock faulted-contact thickness lower limit for oil-gas sealing was established by comparing the sealing ability of fault rock and underlying reservoir rock.The method was applied to the No.1 structure of Nanpu sag, where a prediction on the lower limit of the Ng₃ volcanic caprock faulted-contact thickness for sealing the oil-gas in underlying Ed₁ was made. The results indicate that the caprock faulted-contact thickness required by oil-gas sealing at fault f₁, f₂, f₃ and f₄ are all less than the actual faulted-contact thickness of Ng₃ volcanic caprock, thus oil-gas are all sealed in the underlying Ed_1reservoir, which is consistent with the current oil-gas distribution in the Ed₁. This method is thus applicable to study the caprock faulted-contact thickness lower limit required by oil-gas sealing.