微地震震源定位方法综述

Summary of Microseismic Location Methods

微地震震源定位方法是微地震监测领域的一项核心技术,而考量微地震技术应用效果好坏的准则在于震源定位方法的精确程度。针对非常规油气开发过程中微地震震源定位方法的应用,本文对微地震震源定位方法进行阐述。其中:几何作图法具有稳健、效率高的优势,但震源位置较深时定位精度较低;线性定位法无需速度模型精度,但对初至拾取的精度有较大影响;非线性定位法对初至拾取较为敏感,对速度模型的精度要求较高,但计算量较小;混合优化定位法在一定程度上提高了定位的精度和效率,但在低信噪比、速度模型精度较低时优势不明显;基于波形偏移的定位方法无需考虑初至拾取的精度,但计算量较大;基于神经网络的定位方法采用训练网络进行训练,定位精度高,误差小。同时,本文还介绍了多方法多参数信息融合技术在油气藏微震震源定位中的应用。

Microseismic positioning method is a core technology in the field of microseismic monitoring,and the criterion to consider the application effect of microseismic technology lies in the accuracy of the source positioning method.Given the application of unconventional oil and gas development in microseismic positioning,the authors expound on the microseismic positioning methods.Among them,the geometric mapping method has the advantages of robustness and high efficiency,but its positioning accuracy is low when the source location is deep;the linear positioning method does not need the accuracy of the velocity model,but has a great impact on the accuracy of first break pick-up;the nonlinear positioning method is more sensitive to first break picking and requires higher accuracy of the velocity model,but the calculation is small;the hybrid positioning method improves the positioning accuracy and efficiency to a certain extent,but the advantages are not obvious when the signal-to-noise ratio is low,and the speed model precision is not high;the positioning method based on waveform migration does not need to consider the precision of first break pick-up,but the calculation is large;the positioning method based on neural network using training network training is highly accurate,and the error is small.The authors also discuss the application of multi-method and multi-parameter information fusion technology in microseismic location of oil and gas reservoir.