OK I'll check the videos later. You seem right about the aftershocks. I wouldn't say to take wikipedia at face value, but for the moment here's what is said;
http://en.wikipedia.org/wiki/Earthquake ... arthquakes
Earthquakes can be recorded by seismometers up to great distances, because seismic waves travel through the whole Earth's interior. The absolute magnitude of a quake is conventionally reported by numbers on the Moment magnitude scale (formerly Richter scale, magnitude 7 causing serious damage over large areas), whereas the felt magnitude is reported using the modified Mercalli intensity scale (intensity II–XII).
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http://en.wikipedia.org/wiki/Moment_mag ... arthquakes
As far as we can tell, the value obtained from the logarithmic scale is the one used to obtain the energetic value.
Anyway, I complicated matters because the relevant wave is the greatest one. Anything else, being weaker, won't make a difference if the most powerful one didn't threaten the target.
Since the focus = epicenter, it's most logical to look for very shallow focus earthquakes as a reference, or better, anything related to nukes, as you know.
http://en.wikipedia.org/wiki/Seismic_sc ... _intensity
http://en.wikipedia.org/wiki/Depth_of_f ... ctonics%29
http://en.wikipedia.org/wiki/Moment_mag ... explosions :
Such comparison figures are not very meaningful. As with earthquakes, during an underground explosion of a nuclear weapon, only a small fraction of the total amount of energy transformed ends up being radiated as seismic waves. Therefore, a seismic efficiency has to be chosen for a bomb that is quoted as a comparison. Using the conventional specific energy of TNT (4.184 MJ/kg), the above formula implies the assumption that about 0.5% of the bomb's energy is converted into radiated seismic energy Es. For real underground nuclear tests, the actual seismic efficiency achieved varies significantly and depends on the site and design parameters of the test.
0.5% means that you'd have to multiply the energy value by 200 to know what a nukes does.
There are two caveats with that though.
Firstly, depending on your conception of a TL bolt, either you believe it's a beam, thus more or less entirely directed into the ground with (although the blast crater it's still exposed to the sky) or it's more like some kind of bottled particle system, either where it's already some kind of superheated plasma that is self-contained and just needs to hit something, basically, to have its membrane pop, or it's more like a simile bomb which will react on impact.
The latest model potentially leading to the most explosive reaction, and thus the more blast and shockwave.
To me, from visual evidence and else, turbolaser bolts would
not have anywhere the
power of a nuke, especially according to the first model. From movies to shows, explosions induced by TL bolts don't look particularly violent.
The delivery of energy into the ground is solely based on the timeframe the bolt requires to deposit its energy. In the particle beam model, it is precisely the speed of the beam and its length which define how many particles get dumped into a given spot over a given time.
Secondly, this directly impacts on the efficiency of the weapon as the explosion will not happen underground, contrary to what is quoted above.
This is where it gets tricky because although a more violently explosive reaction would, in my opinion, produce more blast, there's the problem that unless it was focused by magitech, the explosion would largely be omnidirectional.
I don't remember the factor between an enclosed bomb and one exposed to air, but I think I read it was about four or something. What I mean is that once you'd have the value for your "underground" nuke, in order to get an adequate yield for your "surface" nuke, you may need to multiply the "underground" result by four.
