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位于印度洋由5个小声纳台阵构成的台网无先例地记录到了与2004年12月26日苏门答腊特大逆断层地震相关的声纳信号,这些声纳台阵距离震中约2800~7000km。每个台阵都记录到由这次地震产生的声波(也称为T波)。通过在T波尾波持续时间内用短时间窗分析后表明,作为时间函数的源方位角接收器变化缓慢。这一分析也表明了视T波波源并不是静止的。视T波波源以2km/s的平均速度沿着巽他海沟向北移动,与这次地震的破裂轨迹很相似。声纳数据说明了地震破裂过程明显地分为2个阶段,刚开始是以大约2·4km/s沿着巽他海沟朝西北方向破裂。到了距离震中600km附近破裂速度下降至大约1·5km/s,但仍朝着西北继续扩展。
A network of 5 small sonar arrays in the Indian Ocean recorded without precedent the sonar signals associated with the Great Sumatra Fault of the Sumatra earthquake on December 26, 2004, which ranged from about 2,800 to 7,000 km. Each array records sound waves (also called T waves) generated by this earthquake. The analysis of the short-time window over the duration of the T-wave coda shows that the source azimuth receiver as a function of time changes slowly. This analysis also shows that the T wave source is not stationary. Depending on the T-wave source moving northward along the 巽tai trench at an average velocity of 2km / s, the rupture trajectory of this earthquake is very similar. Sonar data show that the earthquake rupture process is clearly divided into two phases, beginning with a northwesterly rupture along the Thaeta trench at about 2.4 km / s. At a distance of 600 km from the epicenter, the rupture rate dropped to about 1.5 km / s but continued to expand in the northwest.