Analysis and modelling of tsunami-induced tilt for the 2007, M = 7.6, Tocopilla and the 2010, M = 8.8 Maule earthquakes, Chile, from long-base tiltmeter and broadband seismometer records
Analysis and modelling of tsunami-induced tilt for the 2007, M = 7.6, Tocopilla and the 2010, M = 8.8 Maule earthquakes, Chile, from long-base tiltmeter and broadband seismometer records
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根据长基座倾斜仪和宽带地震仪记录，对 2007 年托科皮亚 (Tocopilla) 海啸引发的倾斜和 2010 年 M = 8·8 智利莫莱地震进行分析和建模
DOI：
10.1093/gji/ggt123
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发表时间：
2010
影响因子：
2.8
通讯作者：
Kammenthaler
中科院分区：
文献类型：
--
作者：
Boudin;Allgeyer;Bernard;Hébert;Madariaga;El-Madani;Vilotte;Peyrat;Nercessian;Schurr;Esnoult;Kammenthaler
我们提出了海啸引起的倾斜在内陆站点的详细研究，以测试这种分析对海啸探测和建模的兴趣和可行性。我们研究了智利北部的倾斜仪和宽带地震仪记录，发现了2007年Tocopilla （M= 7.6）和2010年Maule （M= 8.8）地震引发的海啸的明显特征。我们发现这些记录以海底弹性载荷引起的倾斜为主，水平重力吸引的影响很小。我们利用Delouiset等人提出的震源模型和一张水深图，正确地拟合了该地区（安托法加斯塔、伊基克和阿利卡）的三个潮汐计记录，对Maule海啸进行了建模。在所有最近的站点（7个STS2, 2个长基倾斜仪），我们正确地模拟了Maule海啸前几个小时的倾斜仪信号。唯一的相位不匹配是在离海洋更近的地方。在距离海岸线7 km处，海平面振幅变化10 cm时，倾斜响应为0.005-0.01 μm。对于Maule地震，我们观察到在海啸到达前20分钟在最近的海岸线上有一个明显的倾斜信号。这种倾斜或地震传感器在海啸到来之前探测到远处海啸的能力已经在秘鲁南部-智利北部地震间隙的一个大型逆冲情景中得到了成功的测试。然而，对于台站附近的大事件，这种分析可能不再可行，因为预计长周期地震信号的大振幅会模糊加载信号。海啸的内陆倾斜测量平滑了海平面扰动的短波长，通常是未建模的波长，从而提供了可靠的大规模海啸图像。此外，即使是最大的上升，倾斜测量也不会达到饱和，也不会受到近海海啸的破坏。因此，倾斜仪和宽频地震仪是监测海啸的重要仪器，可与潮汐计阵列配合使用。
We present a detailed study of tsunami-induced tilt at in-land sites, to test the interest and feasibility of such analysis for tsunami detection and modelling. We studied tiltmeter and broadband seismometer records of northern Chile, detecting a clear signature of the tsunamis generated by the 2007 Tocopilla (M= 7.6) and the 2010 Maule (M= 8.8) earthquakes. We find that these records are dominated by the tilt due to the elastic loading of the oceanic floor, with a small effect of the horizontal gravitational attraction. We modelled the Maule tsunami using the seismic source model proposed by Delouiset al.and a bathymetric map, correctly fitting three tide gauge records of the area (Antofagasta, Iquique and Arica). At all the closest stations (7 STS2, 2 long-base tiltmeters), we correctly modelled the first few hours of the tilt signal for the Maule tsunami. The only phase mismatch is for the site that is closer to the ocean. We find a tilt response of 0.005–0.01 μm at 7 km away from the coastline in response to a sea level amplitude change of 10 cm. For the Maule earthquake, we observe a clear tilt signal starting 20 min before the arrival time of the tsunami at the nearest point on the coastline. This capability of tilt or seismic sensors to detect distant tsunamis before they arrive has been successfully tested with a scenario megathrust in the southern Peru-northern Chile seismic gap. However, for large events near the stations, this analysis may no longer be feasible, due to the large amplitude of the long-period seismic signals expected to obscure the loading signal. Inland tilt measurements of tsunamis smooth out short, often unmodelled wavelengths of the sea level perturbation, thus providing robust, large-scale images of the tsunami. Furthermore, tilt measurements are not expected to saturate even for the largest run-ups, nor to suffer from near-coast tsunami damages. Tiltmeters and broadband seismometers are thus valuable instruments for monitoring tsunamis in complement with tide gauge arrays.
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DOI：
10.1785/0120050625
发表时间：
2009
期刊：
The School science review
影响因子：
--
作者：
Johan A. Linthorst
通讯作者：
Johan A. Linthorst
超高分辨率长基线水管倾斜计，用于记录从地球自由振荡到长期倾斜的小信号
影响因子：
1.6
作者：
N. d'Oreye;W. Zürn
通讯作者：
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对希腊科林斯裂谷 Trizonia 岛进行连续应变和倾斜监测
DOI：
--
发表时间：
2004
期刊：
影响因子：
--
作者：
P. Bernard;F. Boudin;S. Sacks;A. Linde;P. Blum;C. Courteille;M. Esnoult;H. Castarède;S. Felekis;H. Billiris
通讯作者：
H. Billiris
地球上的潮汐
DOI：
10.1029/tr031i003p00357
发表时间：
1950
期刊：
Eos, Transactions American Geophysical Union
影响因子：
--
作者：
E. Nishimura
通讯作者：
E. Nishimura
影响因子：
2.8
作者：
S. Peyrat;R. Madariaga;E. Buforn;J. Campos;G. Asch;J. Vilotte
通讯作者：
S. Peyrat;R. Madariaga;E. Buforn;J. Campos;G. Asch;J. Vilotte