From: firstname.lastname@example.org(Nancy )
Subject: Re: TUNGUSKA
Date: 7 Mar 1997 16:00:14 GMT
In article <email@example.com> Jim
>>> And where is this "wet recently deposited volcanic ash"
>>> you mention? The Tunguska region is covered in
>>> swampy peat bogs and permafrost, not by volcanic ash.
>>> jscotti@LPL.Arizona.EDU (Jim Scotti)
>> (Begin ZetaTalk[TM])
>> You answered your own question. Check out the
>> permafrost, a permanently frozen layer of earth. Where the
>> few inches above the permafrost, perhaps a foot or two, melt
>> during the summer months due to warmed air and increased
>> sunlight, the permafrost layer, as the name implies, is
>> PERPETUALLY FROZEN.
>> (End ZetaTalk[TM])
>Just how much methane does it take to cause a blast with the
> explosive power of 15-20 megatons of TNT? And what are
> the dynamics of such an explosion? The nearest eyewitnesses
> were a few 10s of kilometers away and they saw a mushroom
> cloud rise into the sky and shortly afterwards, were hit by the
> shock wave from the blast.
> jscotti@LPL.Arizona.EDU (Jim Scotti)
What happens when natural gas leaks into rooms in a home, without venting sufficiently? Big, huge explosions! Homes are reduced to splinters! Methane is a component of natural gas. If methane gas is trapped under the permafrost in one place due to rotting vegetation, then this would be true of the whole area. And something causing the permafrost to fracture, such as an earthquake or earth movement, would affect MANY spots that would hiss gas. Everyone's making out like methane is not explosive, that this is an unbelievable scene. My Britannica lists methane as an "industrial hazard", and says:
Methane (CH4) a colorless, ordourless gas formed by decaying vegetable matter, may be a hazard in coal mines. It acts as a simple asphyxiant. Miners may be overcome if concentrations are high enough to cause oxygen deprivation; fortunately, in such circumstances the miners fall to the ground, where concentrations are lower because methane is lighter than air, and thus they may recover. Methane, also known as firedamp, produces an explosive mixture with air at relatively low concentrations. Such accidents are now rare, because dangerous concentrations of methane may be detected by flame safety lamps.
In other words, it doesn't take a large amount of methane, mixed with air, to create an explosion. If such a situation were spread out over a LARGE area of tundra, and extended upwards to form a LARGE THICK CLOUD then it would be a BIG explosion.