International Scientific Meeting“Frontiers of Source Studies
for the 2011 Tohoku Earthquake”

April 4~6, 2012
Koshiba Hall, Faculty of Science,
University of Tokyo, Japan

Supported by Japan Society for the Promotion of Science;
Earthquake Research Institute, University of Tokyo; andAgence Nationale de la RechercheScopeThe 2011 off the Pacific Coast of Tohoku earthquake (hereafter we call it the 2011Tohoku earthquake) is a megathrust event (magnitude 9.0 to 9.1) in the zone along theJapan Trench, where the Pacific plate is subducting beneath the Tohoku district. Since
this earthquake caused severe damage to Japan resulting in the Great East Japan
Earthquake Disaster, it is one of missions for seismologists to investigate what really
happened and contribute to the mitigation of future earthquake disaster.
The 2011 Tohoku earthquake is the first megathrust event that was observed by dense
networks of geophysical instruments. Accordingly, this earthquake has been a researchtarget for the global community of seismologists. We invite seismologists not only fromUSA but also from France, Italy, and Singapore, where there are research centers forrecent megathrust events, in order to establish international collaboration of sourcestudies on the 2011 Tohoku earthquake. We also discuss the mitigation of disaster by
future megathrust events in various subduction zones, considering problems such thatJapanese seismologists failed to foresee this earthquake.

Kazuki Koketsu
Earthquake Research Institute
University of Tokyoi

Invited Speakers
Thorne Lay
Kunihiko Shimazaki
Toru Matsuzawa
Miaki Ishii
Hisashi Nakahara
Kojiro Irikura
Kerry Sieh
Kenji Satake
Takane Hori
Stefano Lorito(University of California, Santa Cruz, USA)
(University of Tokyo, Japan)(Tohoku University, Japan)(Harvard University, USA)
(Tohoku University, Japan)(Aichi Institute of Technology, Japan)(Nanyang Technological University, Singapore)(University of Tokyo, Japan)(JAMSTEC, Japan)

Takeshi Sagiya
Yuichiro Tanioka
Raul Madariaga
Satoshi Ide
Hiroo Kanamori(Nagoya University, Japan)(Hokkaido University, Japan)(Ecole Normale Superieure, France)(University of Tokyo, Japan)(California Institute of Technology, USA)

(Istituto Nazionale di Geofisica et Vulcanologia, Italy)iiCooperative Members
Kazuki Koketsu
Kenji Satake
Shin’ichi Sakai
Tomomi Okada
Yuji Yagi
Shin’ichi Miyazaki
Yoshiko Yamanaka
Yushiro Fujii
Satoshi Ide
Takeshi Sagiya
Naoki Nishimura
Yusuke Yokota
James MoriKojiro Iirkura
Hisashi Nakahara
Ryou Honda(University of Tokyo)(P.I.)(University of Tokyo)(University of Tokyo)(Tohoku University)(University of Tsukuba)(Kyoto University)(Nagoya University)(Building Research Institute)(University of Tokyo)(Nagoya University)(University of Tsukuba)(University of Tokyo)(Kyoto University)(Aichi Institute of Technology)(Tohoku University)

Kimiyuki Asano
Hiroe Miyake(Kyoto University)(University of Tokyo)(Hot Springs Research Institute of Kanagawa Prefecture)

Local Organizing Committee
Kazuki Koketsu
Hiromi Yokoyama
Hiroe Miyake
Yusuke Yokota(ERI, University of Tokyo)(Faculty of Science, University of Tokyo)(ERI, University of Tokyo)(ERI, University of Tokyo)iii

Program
April 4 (Wednesday)
12:30 - 13:00

13:00 - 13:15

13:15 - 13:45

Registration
Introductory Session
Takehiro Koyaguchi (Director, Earthquake Research Institute,
University of Tokyo, Japan)
Opening address
Kazuki Koketsu (University of Tokyo, Japan)
Discussion points of this meeting and our contributions
Session I

13:45 - 14:30

Thorne Lay (University of California, Santa Cruz, USA)
What do we learn by comparing the 2011 Tohoku earthquake withother recent great earthquakes?

14:30 - 15:00

Kunihiko Shimazaki (University of Tokyo, Japan)
The giant tsunami had been foreseen, but not been included in disaster
design

15:00 - 15:30

Toru Matsuzawa (Tohoku University, Japan) and Yoshihisa Iio
Reasons why we failed to anticipate the 2011 M9.0 Tohoku
earthquake

15:30 - 15:45

Coffee Break

15:45 - 16:30

Session II
Miaki Ishii (Harvard University, USA)
Cascading failure of the plate interface and hidden earthquakes

16:30 - 17:00

Hisashi Nakahara (Tohoku University, Japan)
High-frequency seismic energy radiation from the 2011 Tohoku
earthquake (Mw 9.0)

iv

17:00 - 17:30

Kojiro Irikura (Aichi Institute of Technology, Japan) andSusumu KurahashiSource model of generating strong ground motions during the 2011
Tohoku earthquake and a recipe of predicting ground motions formega-thrust earthquake

18:00 - 20:00

Reception
April 5 (Thursday)

10:00 - 10:45

Session III
Kerry Sieh (Nanyang Technological University, Singapore)
Patterns of large megathrust earthquakes in Sumatra over the pastmillennium

10:45 - 11:15

Kenji Satake (University of Tokyo, Japan)
Past and 2011 tsunamis along the Japan trench and the tsunami hazard
assessments for nuclear power plants

11:15 - 11:45

Takane Hori (JAMSTEC, Japan)
Earthquake generation cycle models for the 2011 Tohoku earthquake
and future megathrust earthquakes in the Nankai subduction zone

11:45 - 13:00

Lunch

13:00 - 13:45

Session IV
Stefano Lorito (INGV, Italy)
Hints (and open issues) for tsunami hazard assessment from recent
mega-thrust earthquakes

13:45 - 14:15

Takeshi Sagiya (Nagoya University, Japan)
Earthquake deformation cycle along the Japan Trench: What we havelearned from the 2011 Tohoku earthquake and unresolved issues

14:15 - 14:45

Yuichiro Tanioka (Hokkaido University, Japan) and Aditya R. Gusman
Possibility of tsunami early warning using W-phase inversion andtsunami inundation modeling as a case study for the 2011 Tohokuv

earthquake
14:45 - 15:00

15:00 - 15:45

15:45 - 16:15

Coffee BreakSession VRaul Madariaga (Ecole Normale Superieure, France) and Sergio Ruiz
High and low frequency radiation by the 2010 Maule
mega-earthquake in Central Chile from cGPS and accelerograms:
Comparison with the 2011 Tohoku earthquake
Satoshi Ide (University of Tokyo, Japan)
Rupture dynamics of the 2011 Tohoku earthquake
Concluding Session

16:15 - 17:00

Hiroo Kanamori (California Institute of Technology, USA)
Looking toward the future

17:00 - 17:10

Closing
April 6 (Friday)

10:00 - 12:00

10:00 - 15:00

Group Discussions
Ground Motion Group
Discussion on strong motion generation areas of megathrustearthquakes
Earthquake Source Physics Group
Discussion on the source physics of megathrust earthquakes

vi