Japan has more measurable earthquakes than any other country and has over 100 active volcanoes. These both result from Japan being wedged among four major tectonic plates.
The tectonics are complicated, but in this animation, IRIS attempted to look at the basic mechanics of the region as they focused on two famous earthquakes: the 1995 Kobe (Great Hanshin) earthquake and the 2011 Tohoku-Oki earthquake. It is necessarily simplified to depict basic processes.
Video courtesy IRIS
Although there are many published fault-displacement models derived from fitting different sets of observations (teleseismic waveforms, tsunami heights, GPS displacements, seafloor deformation, etc.), there is considerable disagreement between those fault-displacement models.
For a variety of reasons, the animation group decided to illustrate the fault-displacement model of Jiang and Simons, 2016, Journal of Geophysical research, 10.1002/2016JB013760.
Written & directed by Dr. Robert F. Butler, University of Portland
Animation & graphics by Jenda Johnson, Earth Sciences Animated
Narrated by Wendy Bohon, Informal Education Specialist, IRIS
Dr. Hiroyuki Tsutsumi, Doshisha University (堤 浩之, 同志社大)
Dr. Chris Goldfinger, Oregon State University
Dr. Lori Dengler, Humboldt State University
Featured image credit: Incorporated Research Institutions for Seismology (IRIS)