Fig. 7
From: Earthquakes in Oita triggered by the 2016 M7.3 Kumamoto earthquake
Events possibly triggered by mainshocks. a The green circles show the events of all magnitudes during March 11–March 17, 2011, possibly triggered by the M9.0 Tohoku-oki earthquake. The red circles show the events of all magnitudes during the first week after the M7.2 West off Fukuoka prefecture earthquake of March 20, 2005. The purple circle shows the M4.1 event which occurred 1 day after the M6.4 central Oita earthquake of April 21, 1975. The gray circles denote the events which occurred on the same day of the M7.2 Hyuganada earthquake of November 19, 1941. The blue circles show epicenters of the 2016 M ≥ 3 aftershocks. b Depth distributions. Those of 1975 and 1941 events have large errors. The green diamonds in a, b denote the hypocenter of the M5.7 event relocated in this study