Allen wrote:
>All asteroid impacts creating impact craters are the same as un-contained
>underground blasts. These asteroids are so big that the air does not cause
>enough compression. It is only after entering the ground that critical
mass is
>reached. The blast of an un-contained underground blast is even less
>destructive than a surface blast. The bright flash is fully contained
>underground, so instant fires cannot happen. The shock wave is directed
almost
>entirely upward. A much diminished shock wave does follow along on the
ground.
>Most of the energy of the blast is absorbed into moving the earth outward
and
>upward.
Allen,
I will re-post what I posted before about all the different killing
mechanisms of a major impact crater. Even if most of the energy is directed
upward, enough goes around the earth to kill everything, or nearly
everything. Maybe you should try to answer this data, which you didn't last
time and apparently you still haven't incorporated it into your thinking.
Here is what I posted before. Please deal with each of these killing
mechanisms before you say that the flood was caused by such an event.
re-post:
"Computer models of explosions with energies of 1,000 megatons--about 20
times the energy of the largest nuclear bombs but only 1/100,000 the energy
of the KT impact--have shown that the fireball never reaches pressure
equilibrium with the surrounding atmosphere. Instead, as the fireball
expands to altitudes where the density of the atmosphere declines
significantly, its rise accelerates and the gas leaves the atmosphere at
velocities fast enough to escape the earth's gravitational field. The
fireball from an even greater asteroid impact would simply burst out the
top of the atmosphere, carrying any entrained ejecta with it, sending the
material into orbits that could carry it anywhere on the earth."
"The impact of a comet-size body on the earth, creating a crater 150
kilometers in diameter, would clearly kill everything within sight of the
fireball. Researchers are refining their understanding of the means by
which an impact would also trigger extinction worldwide. Mechanisms
proposed include darkness, cold, fire, acid rain and greenhouse heat.
"In our original paper, we proposed that impact-generated dust caused
global darkness that resulted in extinctions. According to computer
simulations made in 1980 by Richard P. Turco of R&D Associates, O. Brian
Toon, of the National Aeronautics and Space Administration and their
colleagues, dust lofted into the atmosphere by the impact of a 10-kilometer
object would block so much light that for months you would literally be
unable to see your hand in front of your face.
"Without sunlight, plant photosynthesis would stop. Food chains everywhere
would collapse. The darkness would also produce extremely cold
temperatures, a condition termed impact winter. (After considering the
effects of the impact, Turco, Toon and their colleagues went on to study
nuclear winter, a related phenomenon as capable of producing mass
extinctions today as impact winter was 65 million years ago.)
"In 1981 Cesare Emilliani of the University of Miami, Eric Krause of the
University of Colorado and Eugene M. Shoemaker of the USGS pointed out that
an oceanic impact would loft not only rock dust but also water vapor into
the atmosphere. The vapor, trapping the earth's heat, would stay aloft much
longer than the dust, and so the impact winter would be followed by
greenhouse warming. More recently John D. O'Keefe and Thomas J. Ahrens of
the California Institute of Technology have suggested that the impact might
have occurred in a limestone area, releasing large volumes of carbon
dioxide, another greenhouse gas. Many plants and animals that survived the
extreme cold of impact winter could well have been killed by a subsequent
period of extreme heat.
"Meanwhile John S. Lewis, G. Hampton Watkins, Hyman Hartman and Ronald G.
Prinn of the Massachusetts Institute of Technology have calculated that
shock heating of the atmosphere during impact would raise temperatures high
enough for the oxygen and nitrogen to combine. The resulting nitrous oxide
would eventually rain out of the air as nitric acid--an acid rain with a
vengeance. This mechanism may well explain the widespread extinction of
marine invertebrate plants and animals, whose calcium carbonate shells are
soluble in acidic water.
"Another killing mechanism came to light when Wendy Wolbach, Ian Gilmore
and Edward Anders of the University of Chicago discovered large amounts of
soot in the KT boundary clay. If the clay had been laid down in a few years
or less, the amount of soot in the boundary would indicate a sudden burning
of vegetation equivalent to half of the world's current forests. Jay Meos
of the University of Arizona and his colleagues have calculated that
infrared radiation from ejecta heated to incandescence while reentering the
atmosphere could have ignited fires around the globe." Walter Alvarez and
Frank Asaro, "An Extraterrestrial Impact," Scientific American, Oct. 1990,
p. 80-82
Then Allen asked:
>Is this all accounted for in your program?
My program calculated flightpath the megatonnage yield and crater or
airblast size (although right now it underestimates the airblast size).
glenn
Foundation, Fall and Flood
Adam, Apes and Anthropology
http://www.flash.net/~mortongr/dmd.htm
Lots of information on creation/evolution
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