*Taku Ueda¹, Aitaro Kato¹ (1.Earthquake Research Institute, the University of Tokyo)

*Aitaro Kato¹, Taku Ueda¹ (1.Earthquake Research Institute, the University of Tokyo)

*Kei Katsumata¹, Mako Ohzono¹, Hiroshi Aoyama¹, Ryo Tanaka¹, Masamitsu Takada¹, Masayoshi Ichiyanagi¹, Teruhiro Yamaguchi¹, Kazumi Okada¹, Hiroaki Takahashi¹, Shin'ichi Sakai², Satoshi Matsumoto³, Tomomi Okada⁴, Toru Matsuzawa⁴, Shuichiro Hirano⁵, Toshiko Terakawa⁶, Shinichiro Horikawa⁶, Masahiro Kosuga⁷, Hiroshi Katao⁸, Yoshihisa Iio⁸, Airi Nagaoka⁸, Noriko Tsumura⁹, Tomotake Ueno¹⁰, the Group for the Aftershock Observations of the 2018 Hokkaido Eastern Iburi Earthquake (1.Institute of Seismology and Volcanology, Faculty of Science, Hokkaido University, 2.Earthquake Research Institute, University of Tokyo, 3.Institute of Seismology and Volcanology, Faculty of Science, Kyushu University, 4.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 5.Nansei-Toko Observatory for Earthquakes and Volcanoes, Graduate School of Science and Engineering, Kagoshima University, 6.Earthquake and Volcano Research Center, Graduate School of Environmental Studies, Nagoya University, 7.Graduate School of Science and Technology, Hirosaki University, 8.Research Center for Earthquake Prediction, Disaster Prevention Research Institute, Kyoto University, 9.Graduate School of Science, Chiba University, 10.National Research Institute for Earth Science and Disaster Prevention)

*Takayuki Kawabe¹ (1.Faculty of Education, Arts and Sciences, Yamagata University)

*Kentaro Hattori¹, Ichiro Nakanishi¹ (1.Kyoto Univ.)

*Shinji Toda¹ (1.International Research Institute of Disaster Science, Tohoku University)