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"Verneshot": Earth
blast
cause of dinosaurs extinction?
By John von Radowitz,
Science Correspondent
21/05/04 (Source URL at end)
The dinosaurs might not
have been the victims of a giant asteroid after all. They
could have been blown out of existence by an almighty
underground explosion with the energy of seven million atom
bombs, according to a new theory. A team of scientists
claims the Earth-shaking blast, called a Verneshot, is the
best explanation for why the dinosaurs were wiped out 65
million years ago. Most experts believe the extinction was
caused by a huge asteroid or comet that smashed into the
Earth off the coast of Mexico.
Others have blamed a
mega-volcanic episode, called a continental blood basalt,
which resulted in numerous vents pouring poison gas into the
atmosphere from a region called the Deccan Traps in India.
But there’s a mystery
that neither theory has been able to solve. The death of the
dinosaurs was not the only mass extinction to have occurred
since complex life emerged on the Earth 400 million years
ago. In fact there have been four. And each one seems to
have coincided both with a continental flood basalt and a
meteorite impact, even though the chances of this happening
are remote.
 The
probability of all four extinctions occurring at the same
time as an impact and continental flood basalt is one in
3,500. But according to the new theory from a team of German
scientists, a Verneshot could answer the riddle and account
for impact evidence such as craters. The name Verneshot
comes from Jules Verne’s book “From the Earth to the Moon”
in which a huge cannon shoots astronauts into space.
The theory suggests what
might happen if a mantle plume, a stream of lava welling up
from deep within the Earth, builds up between a thick chunk
of immovable continent called a craton. If the craton
started splitting, or “rifting”, which could occur every 100
million years, the release of pressure would produce a
catastrophic gas explosion. Gases would surge up and burst
out at the surface, poisoning the atmosphere and causing
severe environmental stress around the world. The blast
would trigger a magnitude 11 earthquake, bigger than any
quake ever recorded.
But this would be just a
prelude to the main event. Immediately after the explosion,
pressure would plummet in the pipe that carried the gases,
causing it to cave in from the bottom upwards. The collapse
would travel up at hypersonic speed, erupting with
unimaginable force at the surface and hurling as much as 20
gigatonnes of rock into the stratosphere.
The energy released would
be equivalent to 120 billion tonnes of TNT, or seven million
of the atom bombs that destroyed Hiroshima at the end of the
Second World War. Debris would rain down from the sky, and
dust would blot out the sun to cause the same kind of
climate changing effects as an impact from space.
A large piece of rock
from a Verneshot blast landing on the Earth would produce a
crater in the same way as an asteroid or comet. An object
ejected from the Deccan Traps could explain why the
Chicxulub crater, linked to the extinction of the dinosaurs,
is so lopsided.
Modellers have concluded
that the impactor must have come in from the south-east at
an angle of about 20 degrees. That doesn’t rule out a
meteorite, but it also fits in with debris flying from the
direction of India.
 The
scientists, led by
Jason Phipps Morgan, at the Geomar Earth Science
Institute, Kiel University, believe all the impact
signatures associated with mass extinctions can be explained
by the Verneshot theory, Deep mantle volcanism, for
instance, would bring the rare element iridium to the
surface, while the explosion would produce quartz crystals
riddled with tiny fractures. Small blobs of melted rock and
carbon particles called fullerines – other hallmarks of a
meteorite impact – could also be formed.
Phipps Morgan, whose
claims were reported in New Scientist magazine, acknowledges
that the theory is very difficult to prove. The best
evidence would be to locate the remains of a Verneshot pipe
buried under kilometres of rock. These should show up on
seismic images and gravity surveys. A “circular gravity
anomaly” relating to disturbed areas of basaltic rock would
be one expected find, says Phipps Morgan.
Though no-one has yet
carried out such a survey in detail, large near-circular
gravity anomalies have been recorded under the Deccan Traps.
The best clue to a Verneshot event would be to find remains
of a projectile inside a crater. Usually the high-speed
approach of a meteorite ensures that it vaporises when it
hits the Earth. Verneshot debris, on the other hand, would
not travel so fast and should leave some remnants at the
crash site.
If rock fragments at the
Chicxulub crater were found to originate from the Deccan
area of India, it would be strong evidence that the
dinosaurs vanished because of a Verneshot.
http://www.meta-religion.com/Archaeology/Other/verneshot_cause_of_dinosuars.htm
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![Science fiction writer Jules Verne, depicted on a mural in Tampa, Florida. [From Wikipedia].](images/Jules_verne_mural.jpg)
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a writer of popular science and technology books and
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I'm
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