Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data.
Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data.
复制标题
DOI：
10.1038/srep05631
复制
发表时间：
2014-07-09
影响因子：
4.6
通讯作者：
Cocco M
中科院分区：
文献类型：
--
作者：
Romano F;Trasatti E;Lorito S;Piromallo C;Piatanesi A;Ito Y;Zhao D;Hirata K;Lanucara P;Cocco M
2011年东北地震(Mw=9.1)突出了以前未观察到的大型逆冲事件的特征，如相对有限区域的大滑动和浅层破裂传播。我们使用有限元模型，考虑了直到海沟带的三维几何和结构的复杂性，并进行了海啸和大地测量数据的联合反演，以求取地震滑移分布。我们得到了主深滑动与局部地震速度异常之间的密切空间相关性，以及与地震观测到的低频辐射相一致的向北延伸的大的浅层滑动。这些观察表明，摩擦控制了破裂，最初限制了更深的破裂，然后推动它向上传播到海沟，在那里它横向传播。这些发现与地震和海啸风险评估相关，因为它们可能有助于发现巨型断裂沿线容易破裂的区域，并限制海沟附近高度滑动的可能性。我们估计的日本海沟快钻钻井区周围约40 m的滑移值有助于将温度测量得到的断层的动剪切应力和摩擦系数分别限制在约0.68 Mpa和~0.10。
The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively.
登录
查看更多内容
日本海沟至日本海本州弧的地震非均质性和各向异性
影响因子：
2.8
作者：
Huang, Zhouchuan;Zhao, Dapeng;Wang, Liangshu
通讯作者：
Wang, Liangshu
重新定位 2011 年东北冲地震（震级 6.0 至 9.0）
影响因子：
2.9
作者：
Huang, Zhouchuan;Zhao, Dapeng
通讯作者：
Zhao, Dapeng
影响因子：
3
作者：
Kubo, Hisahiko;Kakehi, Yasumaro
通讯作者：
Kakehi, Yasumaro
影响因子：
3
作者：
Fujii, Yushiro;Satake, Kenji;Kanazawa, Toshihiko
通讯作者：
Kanazawa, Toshihiko
影响因子：
3.9
作者：
Lorito, S.;Piatanesi, A.;Melini, D.
通讯作者：
Melini, D.