**5. Acknowledgment**

The authors would like to thank DONET members, Takane Hori and Ryoko Nakata for giving beneficial comments. The authors also would like to thank Tohoku University researchers, Toru Matsuzawa, Ryota Hino and Akira Hasegawa for stimulating our study. J.-P. Ampuero helped us to improve our manuscript with thoughtful discussion. We appreciate publishing managers Igor Babic and Ivana Lorkovic for encouraging our publication, which was partly supported by Grant-in-Aid for Young Scientists (KAKENHI) 23710212.
