Volcanomagnetic signals associated with the 2001 flank eruption of Mt. Etna (Italy)
Volcanomagnetic signals associated with the 2001 flank eruption of Mt. Etna (Italy)
复制标题
与 2001 年埃特纳火山（意大利）侧翼喷发相关的火山磁信号
DOI：
10.1029/2002gl015481
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发表时间：
2003
影响因子：
5.2
通讯作者：
G. Currenti
中科院分区：
文献类型：
--
作者：
C. Del Negro;G. Currenti
2001年山侧喷发期间，观测到了地磁变化。埃特纳。在利用温度资料从季节热噪声中剔除差异磁场后，我们识别出与不同火山事件有关的总强度变化的三个阶段：(A)与7月12日山顶火山口下记录的震群相关的4nT的快速变化，(B)南翼裂缝快速扩展期间7nT的阶跃变化，随后在7月17日熔岩从裂缝中涌出之前的2nT的偏移，以及(C)3nT的快速变化与7月19日在莱昂谷喷发的裂缝打开相吻合。这些观测结果与火山地磁模型的计算结果一致，在火山地磁模型中，磁场变化是由于不同深度岩浆侵入引起的应力重分布和较浅深度的热退磁作用所产生的。
Geomagnetic changes were observed during the 2001 flank eruption at Mt. Etna. After differential magnetic fields were filtered from the seasonal thermic noise by using temperature data, we recognized three stages in the total intensity changes related to different volcanic events: (a) rapid variation of 4 nT associated with July 12 seismic swarm recorded beneath the summit craters, (b) step‐like variation of 7 nT occurring during the quick propagation of fractures in the south flank, which was followed by the off‐set of 2 nT before July 17 when the lava outpoured from fissures, and (c) quick variation of 3 nT coincident with July 19 eruptive fissures opening up in the Valle del Leone. These observations are consistent with those calculated from volcanomagnetic models, in which the magnetic changes are generated by stress redistribution due to magmatic intrusions at different depth and by the thermal demagnetization at a rather shallow depth.