TY - JOUR
T1 - Tomography of the source zone of the great 2011 Tohoku earthquake
AU - Hua, Yuanyuan
AU - Zhao, Dapeng
AU - Toyokuni, Genti
AU - Xu, Yixian
N1 - Funding Information:
We thank the data centers of the S-net, Hi-net, JMA Unified Earthquake Catalog, and Research Center for Prediction of Earthquakes and Volcanic Eruptions of Tohoku University for providing the high-quality waveform and arrival-time data used in this study. We are very grateful to Dr. Zhiteng Yu for his help for collecting the S-net arrival-time data. We appreciate helpful discussions with Drs. Xin Liu, Jianke Fan, Zewei Wang, Tao Gou, and Yaqian Liu. Prof. C. Satriano, H. Yue, and K. Satake kindly provided their coseismic slip models. This work was supported by research grants to D. Zhao from Japan Society for the Promotion of Science (No. 19H01996), Ministry of Education, Culture, Sports, Science and Techology (MEXT) of Japan under it’s the Second Earthquake and Volcano Hazards Observation and Research Program, as well as the Core Research Cluster of Disaster Science in Tohoku University.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - The mechanism and rupture process of the giant 2011 Tohoku-oki earthquake (Mw 9.0) are still poorly understood due to lack of permanent near-field observations. Using seismic arrival times recorded by dense seismograph networks on land and at ocean floor, we determine a detailed seismic tomography model of the megathrust zone beneath the Tohoku forearc. Our results show that the coseismic slip of the 2011 Tohoku-oki earthquake initiated at a boundary between a down-dip high-velocity anomaly and an up-dip low-velocity anomaly. The slow anomaly at shallow depths near the Japan trench may reflect low-rigidity materials that are close to the free surface, resulting in large slip and weak high-frequency radiation. Our new tomographic model can account for not only large slip near the trench but also weak high-frequency radiation from the shallow rupture areas.
AB - The mechanism and rupture process of the giant 2011 Tohoku-oki earthquake (Mw 9.0) are still poorly understood due to lack of permanent near-field observations. Using seismic arrival times recorded by dense seismograph networks on land and at ocean floor, we determine a detailed seismic tomography model of the megathrust zone beneath the Tohoku forearc. Our results show that the coseismic slip of the 2011 Tohoku-oki earthquake initiated at a boundary between a down-dip high-velocity anomaly and an up-dip low-velocity anomaly. The slow anomaly at shallow depths near the Japan trench may reflect low-rigidity materials that are close to the free surface, resulting in large slip and weak high-frequency radiation. Our new tomographic model can account for not only large slip near the trench but also weak high-frequency radiation from the shallow rupture areas.
UR - http://www.scopus.com/inward/record.url?scp=85081039146&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85081039146&partnerID=8YFLogxK
U2 - 10.1038/s41467-020-14745-8
DO - 10.1038/s41467-020-14745-8
M3 - Article
C2 - 32127532
AN - SCOPUS:85081039146
SN - 2041-1723
VL - 11
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 1163
ER -