"Shortly before the first tower came down, I remember feeling the ground shaking. I heard a terrible
noise, and then debris just started flying everywhere. ... By the time the debris settled from the first
collapse, we started to walk back east, toward West Street, and a few minutes later ... we basically had the
same thing: The ground shook again, and we heard another terrible noise and the next thing we knew the second
tower was coming down." [EMS
Lieutenant Bradley Mann] |
|
Seismographs at Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York, 21 miles
north of the WTC, recorded strange seismic activity on September 11 that has still not been explained. The
Palisades seismic record shows that — as the collapses began — a huge seismic "spike" marked the moment the
greatest energy went into the ground. The strongest jolts were all registered at the beginning of the
collapses, well before the falling debris struck the earth. These unexplained "spikes" in the seismic data
lend credence to the theory that massive explosions at the base of the towers caused the collapses. [AFP] |
 Click for full sized seismic
record |