构造应力场、地震泵和油气运移

Stress Field,Seismic Pumping and Oil-Gas Migration

本文从中国含油气盆地中断层发育区孔隙流体压力分布和构造应力场特征出发，以莫尔国及岩石破裂包络线理论深入探讨了不同条件下造成岩石破裂的机理，指出构造应力是油气运移的动力之一，地震泵在断裂发育区是油气沿断层作垂向运移的重要作用过程。

In some oil - bearing basins of China, the abnormal pressures do not develop, for example the oil - bearing formation of Tertiary in Liaohe Basin and the Jurassic coal measure in Tuba Basin, which are characterized by the near - hydrostatic pressure. Faults and fractures are the main paths of oil and gas migration, and tectonic stress is the principle dynamics of producing faults and fractures. The writer applies graphs of Mohr's stress circle and failure envelope to discuss this mechanism.According to the abnormal records of ground water table and oil - gas production before, at end after the time of strong earthquake in Eastern China during the latest 30 years, the author indicates that the oil - gas migration along the faults is closely related to the seismic pumping mechanism. The active fault leads to the stress relaxation in faults. especially in its upper part, and then the fluid now from the surrounding rocks towards fault. Based on the fluid potential difference between upper and lower part in fault and buoyance, the oil - gas- water may move periodically and gush out in a mixed phase.