Array analysis using circular-wave-front geometry: an application to locate the nearby seismo-volcanic source
Array analysis using circular-wave-front geometry: an application to locate the nearby seismo-volcanic source
复制标题
使用圆形波前几何结构的阵列分析：定位附近地震火山源的应用
DOI：
10.1046/j.1365-246x.1999.00699.x
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发表时间：
1999
影响因子：
2.8
通讯作者：
E. Pezzo
中科院分区：
文献类型：
--
作者：
J. Almendros;J. Ibáñez;G. Alguacil;E. Pezzo
摘要 用于平面波假设中的阵列分析的零滞后互相关技术已被修改为允许波前为圆形。已经进行了综合测试来检查该方法的能力，当源阵列距离不大于阵列孔径的两倍或三倍时，该方法返回输入测试数据。对于这个距离范围，该方法提供了震源的视速度和震中坐标的估计。对于更远的源，该方法等效于基于平面波近似的方法，平面波近似给出源的后方位角和视速度的估计。该方法已应用于南极洲欺骗岛活火山记录的地震数据。选择了35个小群发生的火山长周期事件。结果表明，震中距离阵列较近（0.4至2公里），并沿西南方向排列，与迪塞普申火山断裂系统的主要方向之一一致。
SUMMARY The zero-lag cross-correlation technique, used for array analysis in the hypothesis of plane waves, has been modified to allow the wave front to be circular. Synthetic tests have been performed to check the capability of the method, which returns the input test data when the source‐array distances are not greater than two or three times the array aperture. For this distance range the method furnishes an estimate of the apparent velocity and the epicentral coordinates of the source. For more distant sources the method becomes equivalent to that based on the planar-wave approximation, which gives an estimate of the backazimuth to the source and the apparent velocity. The method has been applied to seismic data recorded at the active volcano located at Deception Island, Antarctica. 35 volcanic long-period events occurring in a small swarm were selected. Results show that the epicentres are close to the array (between 0.4 and 2 km) and aligned in a SW direction, in agreement with one of the main directions of the fracture system of Deception volcano.