William here.There was a question regarding the history of seismic activity in Kumamoto. The link below is a handy chart to earthquake location and estimated magnitude over the last 150 years or so. As you can see, this was the largest quake in the region since the 1890s. http://www.jishin.go.jp/main/yosokuchizu/kyushu-okinawa/p43_kumamoto.jpg