Well... that was my point. HOWEVER, the real problem was that I listed the data from JAN 21, 2012, instead of JAN 21, 2013.
I goofed big time. PJ-COMIX responded to me and listed the correct data in another post, showing seismic activity on that DATE and in that LOCATION.
Bottom line, it appears that there was some kind of explosion.
(Well.... that's two mistakes, wonder what my next one will be?)