断裂—砂体形成油气运移的“中转站”模式

油气运移是当今世界石油地质学中研究最薄弱的环节,也是最前沿的学科,它是成藏动力学研究的核心。断裂是裂陷盆地内重要的油气运移通道,但是断面与烃源岩接触面积小,不能吸收大量油气,大断层下降盘的水下扇砂体与生烃岩大面积接触,能吸收烃源岩中生成的大量油气,当达到一定饱和度时,温—压升高,伴随着断层的“幕式”运动,油气从砂体——中转站中沿断层向上运移成藏。正、反两方面勘探实践验证了断裂—砂体的油气中转站运移模式的正确性,它将对今后油气运移的研究和勘探起到一定的指导作用。

Transfer Station Model of Oil-gas Migration Formed by Fault-sandbody

Oil-gas migration is regarded as the weakest link in petroleum geology research in the world and is the most frontier science as well, and is the core of the dynamic research of oil-gas accumulation and migration. Although fault is the important pathway for oil- gas migration in the faulted-depression basin, the contact plane of the hydrocarbon source rock is small, which cannot absorb a mass of oil and gas. However,in the downthrow block of the major fault, the subsea fan sandbody has large contact plane with the hydrocarbon source rock, which could absorb the most of oil and gas produced in the hydrocarbon rock. While reaching the certain saturation of oil and gas, the temperature and pressure will rise and along with the episodic movement of the fault, oil and gas will migrate upwards in the transfer station of the sandbody along the fault, accumulate, and the reservoir will then be formed. Both the success and the failure practice in exploration proved that the way of model"Oil-gas Transfer Station "of the fault-sandbody is correct, furthermore, it will guide the research and exploration for the oil-gas migration in the future.