Performance of a Rotational Sensor to Decipher Volcano Seismic Signals on Etna, Italy
Performance of a Rotational Sensor to Decipher Volcano Seismic Signals on Etna, Italy
复制标题
用于破译意大利埃特纳火山地震信号的旋转传感器的性能
DOI：
10.1029/2021jb023617
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
M. Weber
中科院分区：
文献类型：
--
作者：
E. Eibl;Martina Rosskopf;M. Sciotto;G. Currenti;G. Di Grazia;P. Jousset;F. Krüger;M. Weber
火山地震信号，如长周期事件和震颤，是火山活动和不稳定的重要指标。然而，它们的波场很复杂，使用传统的地震仪器进行表征和定位往往很困难。在2019年，我们使用新开发的3C旋转传感器与意大利埃特纳的3C传统地震仪共同定位，记录了完整的地震波场。在复杂火山地震信号分析方面，我们比较了旋转传感器、地震仪和意大利国家火山地质研究所（INGV‐OE）地震台网的性能。我们结合STA/LTA算法和相互关联，为火山构造（VT）和长周期（LP）事件创建了事件目录。基于旋转传感器的事件检测与基于地震仪的事件检测一样可靠。LP事件以SH型波为主。得到的SH相速度范围为LP事件500 ~ 1000m /s，火山震颤事件300 ~ 400m /s。在弱火山活动期间，SH -波构成震颤；在持续的火山活动期间，SH -波和SV -波构成震颤。我们使用(a)水平旋转分量和(b)垂直旋转速率和横向加速度推导出反向方位角。对于(a)震中距离大于3 km的VT事件和一些更近的事件，(b) LP事件和主要火山口区域的震颤，估计的反向方位角与INGV‐OE事件位置一致。通过测量完整的波场，我们可以可靠地分析出在火山等难以到达的地区，VT、LP事件和震颤的后方位角、相速度和波场组成。
Volcano‐seismic signals such as long‐period events and tremor are important indicators for volcanic activity and unrest. However, their wavefield is complex and characterization and location using traditional seismological instrumentation is often difficult. In 2019 we recorded the full seismic wavefield using a newly developed 3C rotational sensor co‐located with a 3C traditional seismometer on Etna, Italy. We compare the performance of the rotational sensor, the seismometer and the Istituto Nazionale di Geofisica e Vulcanologia‐Osservatorio Etneo (INGV‐OE) seismic network with respect to the analysis of complex volcano‐seismic signals. We create event catalogs for volcano‐tectonic (VT) and long‐period (LP) events combining a STA/LTA algorithm and cross‐correlations. The event detection based on the rotational sensor is as reliable as the seismometer‐based detection. The LP events are dominated by SH‐type waves. Derived SH phase velocities range from 500 to 1,000 m/s for LP events and 300–400 m/s for volcanic tremor. SH‐waves compose the tremor during weak volcanic activity and SH‐ and SV‐waves during sustained strombolian activity. We derive back azimuths using (a) horizontal rotational components and (b) vertical rotation rate and transverse acceleration. The estimated back azimuths are consistent with the INGV‐OE event location for (a) VT events with an epicentral distance larger than 3 km and some closer events, (b) LP events and tremor in the main crater area. Measuring the full wavefield we can reliably analyze the back azimuths, phase velocities and wavefield composition for VT, LP events and tremor in regions that are difficult to access such as volcanoes.
影响因子：
1.6
作者：
Hadziioannou, Celine;Gaebler, Peter;Igel, Heiner
通讯作者：
Igel, Heiner