August 8, 2024 Earthquake: Miyazaki, Japan

Reference #13456:

Tectonic Summary

The August 8, 2024, M7.1 earthquake northeast of Nichinan, Japan, occurred due to thrust faulting at shallow depth on or near the subduction zone interface between the Philippine Sea plate and the Eurasian plate. Moment tensor solutions for the event indicate rupture on either a shallowing dipping fault striking toward the southwest or a steeply dipping fault striking toward the northeast. The location, depth, and shallow dipping thrust faulting are consistent with slip on the plate interface. At the location of this earthquake, the Philippine Sea plate is moving towards the northwest with respect to the Eurasian plate at approximately 6 cm/yr.

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Thrust faulting events of the size of the August 8, 2024, earthquake are typically about 50 x 20 km in size (length x width).

Large earthquakes are common in Japan. Eight earthquakes M7 and larger have occurred within 250 km of the August 8, 2024, event in the past century. The largest was an M8 that occurred on November 18, 1941, 60 km northeast of this August 8, 2024, earthquake. On February 26, 1961, an M7.5 occurred in nearly the exact location of this August 8, 2024 event. Recently, an April 15, 2016, intraplate earthquake 140 km to the north-northwest of the August 8, 2024, event resulted in 40 fatalities.

Reference #13814:

14 injured, 1 house destroyed, 2 houses damaged