利用克里金技术标定新疆及附近地区P/S震相幅值比及其在地震事件识别中的应用

针对中国的乌鲁木齐台（WMQ）和哈萨克斯坦的马坎奇台（MAK），采用贝叶斯克里金技术建立了新疆及附近地区地震事件的震相幅值比的校正曲面，并分析了校正曲面与地震波传播路径的关系，以及校正曲面对于改善震相幅值比判据识别效果的有效性.分析结果表明，建立的校正曲面基本合理，结合传播路径差异和地震波传播规律，能够较好地解释校正曲面的起伏特征. 而且，在传播路径差异较大，使得震相幅值比经震中距校正后离散度仍然较高的情况下，利用校正曲面修正震相幅值比，可以进一步降低其离散度，从而改善判据的识别效果.经校正曲面修正后，对天然地震的误识率由16.3%下降为5.2％. 

CALIBRATION OF P/S AMPLITUDE RATIOS FOR SEISMIC EVENTS IN XINJIANG AND ADJACENT AREAS BASED ON A BAYESIAN KRIGING METHOD

Correction maps of P/S amplitude ratios for seismic events distributed in Xinjiang, China and adjacent areas were established using a Bayesian kriging method for the two seismic stations WMQ and MAK. The relationship between correction maps and variations of along-path features was analyzed and the validity of applying the correction maps to improve performances of P/S discriminants for seismic discrimination was investigated. Results obtained show that obtained correction maps in general may reflect event-station path effects upon corresponding P/S discriminants; and the correction of these effects could further reduce scatters of distance corrected P/S measurements within earthquake and explosion populations as well as improve their discriminating performances if path effects are a significant factor of such scatters. For example, as corresponding kriging correction map was applied, the misidentification rate of earthquakes by lgPn(2~4 Hz)/Lg(2~4 Hz)] at MAK was reduced from 16.3% to 5.2%.