摘要
本文在研究盖层封闭油气机理的基础上,分析了欠压实泥岩在封盖油气中的作用。欠压实泥岩具有压力封闭油气的能力,既可以封闭呈游离相运移的油气,又可以封闭呈水溶相运移的油气。当泥岩为生烃岩时,欠压实泥岩具有较强的烃浓度封闭能力,可完全封闭呈扩散相运移的天然 气。即使欠压实泥岩中有断裂,因已存在孔隙流体异常压力也会使断层具封闭性。因此,欠压实泥岩是封闭油气最有利的封闭盖层。
Based on the research of the sealing mechanism of caprocks, this paper analyses the role of un-compacted mudstone in sealing oil and gas. Uncompacted mudstone has the capability of pressure sealing, which can not seal only oil and gas in free phase, but also oil and gas in waterdissolving phase. In the case of mudstone to be a source rock, the uncompacted mudstone would have a strong capability of hydrocarbon concentation sealing to seal gas in diffusive phase. Even if uncom-paction mudstone is faulted, faults would be capable to seal off because of the existence of pore-fluid abnormal pressure in uncompacted mudstone. Therefore, uncompacted mudstone is the most favorable cap rock.
出处
《中国海上油气(地质)》
1995年第3期164-168,共5页
China Offshore Oil and Gas(Geology)