I’ve been getting annoyed with the grade school conception of “plate” tectonics where everyone is identifying plates and their relative motions and saying stuff like the Japan Earthquake of 2011 was caused by the Pacific Plate sliding under Japan. It is as if the plates had their own means of locomotion and it ignores the fundamental difference between oceanic and continental “plates”.
The plates are just so much china, if you can indulge me here, and what is really interesting is the spreading centers that push ocean floor and the subduction zones or trenches that may actually draw ocean floor down down.
I recently was sent thus utube of the Japan Earthquakes of 2011.
The earthquake pattern before the major event was what one might expect from a plate sliding under another plate: widely dispersed random events. Beginning with the major event virtually all activity was focused where the Japan Trench meets the Ryukyu Trench and all other activity on both trenches virtually ceased.
Unhappily for Japan, it sits astride this juncture.