干涉走时微地震震源定位方法

本文基于地震波场干涉原理,建立了干涉走时微地震震源定位方法.该方法将两个接收点相对于一个微地震事件的走时差(称为干涉走时)的扰动作为残差函数,通过迭代求解最小残差函数,最终获得震源的空间位置.干涉走时震源定位方法利用两个接收点的到时差消除发震时刻未知和速度模型误差的影响,简化了震源定位算法.数值计算表明,本文提出的干涉走时定位方法在速度模型有误差的情况下仍然可以获得准确的微地震震源定位.

Locating micro-seismic events based on interferometric traveltime inversion

To locate sources of micro-seismic events, a method based on seismic interferometric traveltime is proposed in this paper. This method builds on the concept of seismic wave-field interferometry. In this method, we define the interferometric traveltime as the difference of traveltimes from one seismic source to other two different receivers. The locations of micro-seismic events can be obtained by inverting seismic source's spatial position through iteration to obtain minimum interferometric traveltime residual. We set up a difference objective function to eliminate the seismic origin time in seismic arrival time. It can simplify the micro-seismic locating problem, because it reduces the velocity disturbance's influence on traveltime difference. The examples of the numerical calculation show that this method is stable under the velocity model disturbance, and has the advantage of interferometric locating in the multi-event problem with high accuracy.