基于三分量节点仪监测的微地震定位精度提升方法研究
Research on the Enhancement of Microseismic Localization Accuracy Based on Three-Component Nodal Array Monitoring

微地震定位方法一般可分为S波和P波旅行时差法、震源空间扫描法、相对旅行时法、逆时偏移成像法等。S波和P波旅行时差法一般用于S波和P波初至都比较清晰的情况，比如天然微地震监测和井中微地震监测；震源空间扫描法一般用于地震信号非常微弱的情况。三分量节点仪同时采集XYZ三个方向的数据信号，用于分析定位微地震事件。根据不同的目的层岩性及埋深优选最佳观测系统，从而提高微地震事件定位的准确性，并为储层改造评价提供依据。
The methodologies for microseismic localization can generally be categorized into the S-wave and P-wave travel-time difference method, the source-scanning algorithm, the relative travel-time method, and the reverse-time migration imaging method, among others. The S-wave and P-wave travel-time difference method is typically employed in scenarios where the first arrivals of both S-waves and P-waves are distinctly identifiable, such as in the monitoring of natural microseisms and downhole microseismic events. The source-scanning algorithm is usually applied when the seismic signals are exceedingly weak. A three-component nodal array captures data signals in the X, Y, and Z directions simultaneously, which are then utilized to analyze and locate microseismic events. By optimizing the observation system according to the lithology and depth of the target formation, the accuracy of microseismic event localization can be enhanced, thereby providing a foundation for the evaluation of reservoir stimulation.