辽河坳陷西部凹陷低熟油成藏机理

综合利用地质、地球物理、油气藏地球化学和盆地模拟技术，以盆地演化和流体输导格架为成藏背景，以烃源岩演化和分布规律为基础，以能量场演化及其控制的化学动力学、流体动力学和运动学过程为核心，探讨了辽河坳陷西部凹陷低熟油的成藏机制与分布规律。该区低熟油藏以近源分布为主，低熟烃源岩受特定的构造演化样式、沉积环境及沉积母质的多重控制。超压不甚发育，但凹陷沉降-沉积演化史与温压场演化史、低熟烃源岩生烃排烃史和低熟油充注史存在良好的匹配关系。有效烃源岩分布、能量场演化、流体输导格架及其控制的流体流动样式作为油气成藏的主控因素，共同决定了西部凹陷低熟油藏源控、常压、近距离聚集的成藏模式。

Study on reservoir-forming mechanism of low mature oil in Western Sag,Liaohe Depression

Having applied the technologies of geology, geophysics, oil-gas reservoir geochemistry and basin modeling, the authors of this paper discussed reservoir-forming mechanism and distribution law of the low mature oil in Western Sag, Liaohe Depression based on source rock evolution and its distribution. The reservoir-forming background is basin evolution and fluid transportation framework. The key is energy field evolution and its chemical kinetics, fluid dynamics and kinematics process controlled. Low mature oil reservoirs in this area are mainly close to their source rocks that were specifically determined by structural evolution model, depositional environment and organic matter etc. Overpressure phenomenon is not obvious in this area. Well matching relationship exists among particular subsidence-sediment evolution history, geothermal-pressure field, hydrocarbon generating and expulsing history of low mature source rocks and filling history of low mature oil. The near-source accumulation model of the low mature oil reservoirs with normal pressure in Western Sag is a result of common action of the valid source rocks, energy field evolvement, and fluid transportation framework as well as its fluid flow model controlled.