Per Ben Fulford.

Posted by benjamin
April 20, 2016
In the April 18th Weekly Geopolitical News and Analysis I reported that seismographic evidence from the April 16th earthquake in Southern Japan showed it was a natural earthquake. That was wrong. Below is the seismographic evidence from the National Research Institute for Earth Science and Disaster Prevention.
[link to www.kyoshin.bosai.go.jp]
It shows very clearly the earthquake has the signature of an underground nuclear explosion and not a natural earthquake.
See here for a contrast between a natural earthquake and a nuclear explosion:
[link to pesn.com]
Source: [link to benjaminfulford.net]