油气封盖的主控因素及其作用分析

Main Factors Controlling the Sealing of Oil/Gas and Analysis on Their Action

付广 孟庆芬

FU Guang MENG Qing-fen

大庆石油学院, 黑龙江 安达 151400

Daqing Petroleum Institute, Anda 151400, China

在研究盖层封盖油气作用各种因素的基础上,指出厚度、异常孔隙流体压力和断层封闭性是控制油气封盖的主要影响因素,大厚度盖层原始空间分布连续性好,即使被断裂破坏,也不易失去分布的连续性。大厚度盖层毛细管封闭能力强,易形成异常孔隙流体压力和抑制浓度封闭作用。异常孔隙流体压力可使盖层毛细管封闭能力增强,可使盖层形成抑制封闭作用,使断层具封闭性。断层封闭可以恢复盖层的质量和分布的连续性。

Based on the study of factors influencing the sealing of oil/gas, this paper pointed out thickness, abnormal pore fluid pressure and the sealing of faults to be the main factors controlling the sealing of caprock for oil/gas. The continuity of original space distribution of the caprock with big thickness is good. Even if the caprock with big thickness were destroyed, distribution continuity would not easily lost. The caprock with big thickness owns strong capillary sealing ability, can form abnormal pore fluid pressure and the restraining hydrocarbon concentration sealing. Abnormal pore fluid pressure can enhance capillary sealing ability of caprock and the restraining hydrocarbon concentration sealing ability making faults form sealing. The sealing of faults can recover the quality and the continuity of space distribution of caprock.