Normally, when we experience a quake here in Kashima City it is fairly mild and the house just shakes a bit for ten or fifteen seconds. On the JMA scale (Japan's linear quake scale that measures local effects) we experience a 1 or a 2 out of a possible 7.
Last night was different. Just after 1 am we were awakened by a growing rumbling and then shaking of the house. It felt like a JMA "2" or "3". OK. No big deal. Reassure Momo that all is well and go back to sleep. Nope. Another quake started up then another and another every few minutes - some 12 in all - over the next 45 minutes. And the last two were strongest of all, feeling like a "4" on the JMA scale. Pictures in frames fell over as did wine glasses in a cabinet as the house shook from side to side for what seemed like a long time (sorry, I didn't time it).
The initial quake was 6.3 on the Richter scale and the epicenter was located under the seabed about 50 miles offshore from Kashima. The last quake was a magnitude 6.7 emanating from the same location.
Happily, there was no tsunami generated and there have been no reports of damage.