Observation of earthquake ground motion due to aftershocks of the 2016 Kumamoto earthquake in damaged areas

The 2016 Kumamoto earthquake sequence

Beginning in April 2016, a series of shallow, moderate to large earthquakes with associated strong aftershocks struck the Kumamoto area of Kyushu, SW Japan. An Mj 7.3 mainshock occurred on 16 April 2016, close to the epicenter of an Mj 6.5 foreshock that occurred about 28 hours earlier. The intense seismicity released the accumulated elastic energy by right-lateral strike slip, mainly along two...

Earthquakes in Oita triggered by the 2016 M7.3 Kumamoto earthquake

During the passage of the seismic waves from the M7.3 Kumamoto, Kyushu, earthquake on April 16, 2016, a M5.7 [semiofficial value estimated by the Japan Meteorological Agency (JMA)] event occurred in the central part of Oita prefecture, approximately 80 km far away from the mainshock. Although there have been a number of reports that M < 5 earthquakes were remotely triggered during the passage o...

Source location and mechanism analysis of an earthquake triggered by the 2016 Kumamoto, southwestern Japan, earthquake

The 2016 Kumamoto earthquake (Mw 7.0) occurred in the central part of Kyushu Island, southwestern Japan, on April 16, 2016. The mainshock triggered an event of maximum acceleration 700 gal that caused severe damage to infrastructure and thousands of homes. We investigate the source location of the triggered event, and the timing of large energy release, by employing the back-projection method f...

Renormalization of earthquake aftershocks

Assume that each earthquake can produce a series of aftershock independently of its size according to its “local” Omori’s law with exponent 1+θ. Each aftershock can itself trigger other aftershocks and so on. The global observable Omori’s law is found to have two distinct power law regimes, the first one with exponent p− = 1− θ for time t < t ∗ ∼ κ−1/θ, where 0 < 1−κ < 1 measures the fraction o...

Earthquake Ground Motion