reply to post by TrickoftheShade
I have read part of Quirant's paper criticizing the work of Andre Rosseau, the seismologist who links the seismic readings from 9/11 to explosive
detonations rather than falling debris. Both of these guys are Phd's in their respective disciplines, so it is not going to be easy dissecting their
arguments. In fact I have decided to defer responding to Quirant's paper until I have had a chance to go over Rosseau's paper (also in French)
With one exception. I think Quirant has made a big mistake in one of his appendices to the paper. In the section called Post Scriptum 2, he refers to
the work of a student who has compared the seismic wave spectrums of ten avalanches (real world avalanches for which there are seismic records) with
the seismic wave spectrums of the two large WTC towers.
Quirant relays the findings of this student, which are that the spectrums of the collapses of the towers are uncannily like the spectrums of the ten
avalanches (which themselves are strikingly similar).
I think this is a fatal error because the mechanics of an avalanche, as explained in Quirant's paper are different from the mechanics of the
collapses of the two towers. The fact that the wave spectrums of the two types of incidents are so similar raises a red flag for me.
Quirant sees it as confimation of a simple building collapse on the analogy of a mountain avalanche. But to me, a simple building collapse, at least
in the case of the twin towers should be much different from a simple avalanche and therefore it's seismic spectrum
should be different, not
the same or highly similar.
In the classic avalanche, according to Quirant and his student correspondent, a section of a mountain will (1) break off, (2) free fall to an impact
point (3) tumble down the mountain and finally (4) accumulate in a deposit at some lower level.
Applying this paradigm to the WTC (which Quirant does not do) we have:
(1) structural failure of the tower at the aircraft impact point.
(2) the first collapse to the floor below the impact point.
(3) the ensuing cascading collapses.
(4) the accumulation of the debris at the end of step 3.
The simple fact is that the failure of each floor in the building (in a classical pancake collapse) is analogous to a repetition of steps 1 and 2
over and over again
until step 4. There is no step 3, or tumbling of loose debris in the tower collapses, if they are considered to be simple
Therefore, the seismic profile should not be the same as in the typical avalanche.
And very importantly, if it is
similar to an avalanche, another explanation must be determined for this.
Suppose the towers did not simply collapse but were brought down with explosives. Suppose the detonation of shaped charges, dissipating their forces
was not detected by seismographs but was lost in the seismic clutter of falling debris.
Then, having the supports of the building cut by explosives that left no discernable seismic signature, the seismic signature that was
in fact give an appearance of a typical avalanche because, what was happening to the cut and tumbling steel beams is
to the missing step 3 of the typical avalanche, i.e., the tumbling down a slope of loose debris.
To my mind the similarity of the seismic profiles of the WTC tower collapses to those of an avalanche, suggests that explosives/shaped charges are a
necessary component to any explanation of the collapses.
I think this is fairly cogent reasoning and I'm neither a civil engineer nor a seismologist.
[edit on 15-6-2010 by ipsedixit]