Precise source location of AE doublets by spectral matrix analysis of triaxial hodogram
Precise source location of AE doublets by spectral matrix analysis of triaxial hodogram
复制标题
通过三轴均线图谱矩阵分析精确定位 AE 双峰源
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
H. Niitsuma
中科院分区：
文献类型：
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作者：
H. Moriya;K. Nagano;H. Niitsuma
我们开发了一种精确的相对源定位技术，使用三轴均线图方法中的声发射双峰（AE 双峰）来评估地下扩展裂纹的方向和距离。 AE 双峰是一对在同一裂纹上具有相似波形和相邻位置但发生时间不同的声发射。通过频域分析来估计相对源位置。通过交叉频谱分析，根据 P-S 到达时间延迟的差异确定两个 AE 源之间的相对距离。使用光谱矩阵根据 P 波偏振方向的差异导出相对方向。我们还提出了一种通过使用一组 AE 双峰来优化估计相对位置的方法。通过现场实验证实了估计源位置的准确性。可以估计距离三轴探测器约150 m的人工波源的相对位置，距离误差小于1 m，方位角和倾角的方向误差小于3.8度。该分析在地热田中的 AE 双峰上的应用结果证明了其评估更深的地下裂缝的能力。
We have developed a precise relative source location technique using acoustic emission doublets (AE doublets) in the triaxial hodogram method to evaluate the direction and distance of subsurface extension cracks. An AE doublet is a pair of acoustic emissions with similar waveforms and adjacent locations on the same crack but which occur at different times. The relative source location is estimated by an analysis in the frequency domain. The relative distance between two AE sources is determined from the difference of P-S arrival time delays by cross-spectrum analysis. The relative direction is derived using a spectral matrix from the difference in P-wave polarization directions. We also propose a method to optimize the estimated relative location by using a group of AE doublets. The accuracy of the estimated source location was confirmed by performing field experiments. The relative locations of artificial wave sources about 150 m from a triaxial detector can be estimated with distance errors of less than 1 m, and direction errors of less than 3.8 degrees in both azimuth and inclination. Results of the application of this analysis on AE doublets in a geothermal field demonstrate its ability to evaluate deeper subsurface fractures.