当今世界上对油气田增产以及非常规油气田开发时,应用最广泛最有效的石油工程技术方法是水力压裂。评价水力压裂效果的最成功的方法是微地震监测。国内目前在这方面仍处于起步阶段。通过数值模拟方法,研究不同位置的压裂导致微地震源产生的弹性波场特征,采用相邻井中二分量接收信号进行微地震源反演模拟研究。结合纵波横波的传播时间以及偏振特性等信息,追踪微地震波传播路径,计算声源位置,确定压裂裂缝的前沿,从而达到评估压裂效果的目的。数值模拟结果表明,该方法在微地震监测的声源定位方面有较高的精确度,在微地震监测的反演中有一定的借鉴意义。
Nowadays, the hydraulic fracturing is the most widely applied and most effective way to develop and promote the productivity of oil and gas fields in the world. Micro-seismic monitoring is considered to be the most successful method to evaluate the hydraulic fracturing. However, in China, the application and research on this aspect are still at the initial stage. Numerical simulation is done in this paper to study on the acoustic field characteristics of fractures at different locations and to simulate the two-component micro-seismic monitoring in neighboring wells. The time-arrival properties of P-wave and S-wave, as well as their polarization properties are studied together to improve the veracity and reliability in micro-seismic monitoring. The numerical simulation shows a good accuracy in source localization provided by this approach, which is expected to be a reliable method in improving the performance of micro-seismic monitoring.