摘要
对张北62级地震前京西北地区地震波速比的时空分布特征进行了分析,发现62级地震前,该地区波速比时空分布都出现了较明显的低值异常:下降—低值—恢复—下降—发震的过程。空间分布则为近似椭圆形的低值异常区,异常区外围地区地震平静。对计算结果进行了t检验,波速比的时空变化及t检验结果表明,62级地震前京西北地区地震波速比存在着比较明显的低值异常。
We analysis the time space change of wave velocity ratio in northwest of Beijing before Zhangbei 6 2 earthquake,and find that there is an obvious change,this process includes decline,low value,comeback,decline and happen.The abnormal area in space spread is a ellipse area,and there is a placidity outside the abnormal area.At the end,we check up the statistical result through t test,the result of the abnormal change of wave velocity ratio indicates that there is obvious abnormal low value of wave velocity ratio in northweat of Beijing.
出处
《地震地磁观测与研究》
2000年第1期6-11,共6页
Seismological and Geomagnetic Observation and Research
关键词
京西北地区
波速比
张北地震
地震波
地震
northwest of Beijing,wave velocity ratio,Zhangbei earthquake,low value abnormal
