【摘要】 2005年12月3日—2006年5月18日,中国地震局对山东东营杜邦1井(直井)进行了6个月的注水诱发地震监测.对该井1464~3034m,即纵向跨度1570m的4个注水层段(沙三中、沙三上顶部、沙三上底部、沙二段)11个注水作业过程进行了完整记录.应用长短项平均和多台比较方法共获得地震事件记录5090个,最终获得定位事件274个.监测期间记录到的事件信号能量都比较小,没有ML>0.5的震动信号.从注水开始,事件的数量随时间呈现出不同的变化,在沙三上的中等胶结程度地层中,震动破裂事件最为频繁.破裂事件空间位置随时间从注水中心向外围扩展,在不同的注水层段呈现出不同的方向性:在低渗透储层段,破裂事件的展布趋向与最大水平主压应力方向一致;在中高渗透层段,震动事件更多地沿主渗流通道展布.更多还原

【Abstract】 From December 3, 2005 to May 18, 2006, a water injection-induced seismicity test was conducted on DuPont test well 1 for about six months by China Earthquake Administration. To the vertical injected well, 11 water injection processes were conducted on four depth intervals, including middle Shahejie3, the top of the upper Shahejie3, the bottom of the upper Shahejie3 and Shahejie2, with the vertical span from 1 464 m to 3 034 m. Monitoring stations has been run throughout the procedure. From the recorded data, there were 5 090 events being picked out manually, 274 events located. It indicates that the energy of seismic signal is very small, and the largest magnitude is no more than ML0.5. And also, the major energy is centered on the vertical component, while amplitude of the other horizontal components is very small. From the start of water injection, the number of seismic events varied with time. And the event was most frequent in the period of upper Shahejie3 injection. The distribution of events extended from the injected well to the outside with time, and the direction of events distribution rotated in different injected interval. Of which, in the low permeability interval, events trend close to the direction of principal compressive stress direction; while in higher permeability interval, they trend close to the predominant seepage direction.更多还原