Cyborg's right. Seismologists can tell the difference between an earthquake and a nuclear boom-boom.
I wonder how they can tell. Hmmm... hold on. Let me get my tinfoil and I'll let you know.
Remember the N. Korea explosion that showed up on the meter-thingy. Nobody seemed to know what was up then, as there was no news coming out in regard to the disaster.
How do scientists distinguish between 'boom booms' and earthquakes if there is no communication or access allowed?