[meteorite-list] tunguska explosion data

From: Sterling K. Webb <kelly_at_meteoritecentral.com>
Date: Thu Apr 22 09:52:18 2004
Message-ID: <3D608613.3854CFE1_at_bhil.com>

Hi,

    The tests you are referring to were done on topographic
models to duplicate the pattern of the fallen trees at Tunguska.
There are NO geological features whatsoever at the Tunguska
site. Originally, Kulik (1927) thought the numerous small pits
in the blast valley were small impact craters but they proved to
be just ordinary slumping of the permafrost in an arctic bog,
something that occurs every spring.

    The "butterfly" pattern in the fallen trees has two lobes
that extend to either side of the final flight path of the
Tunguska object. It has been interpreted as resulting from the
compression and deformation of the object by the atmosphere just
before it explosively disintegrated. At any rate, that modeling
of the Tunguska impact has nothing to do with the shape of
craters.

    The form of a crater reveals very little about the incoming
flight of the object that created it since the crater is formed
by a purely explosive event and all really big explosion are
pretty much alike. Craters are circular at almost all flight
angles. Only the very shallowest of impact angles create oval
craters. The very smallest craters are the only ones likely to
show any irregularities.

    Above a few score meters in diameter, craters will be regular
and circular (or regular and oval) when formed. Of course,
erosion, depositation, and all the other forces of earth's
geology will go right to work on that fresh new crater and begin
to modify it...


Sterling K. Webb
--------------------------------------------------------------------------------

alvie roach wrote:

> I am trying to prove a dry lake is in fact a meteorite
> crater.A meteorite was found in the area, the bed rock
> is shattered for miles in every direction and the
> shape of the dry lake seemes to have a ballistic
> signature.I am hopeful someone can help me access the
> experiment data that determined the hight and angle of
> the explosive event at tunguska.the discovery channel
> had a program about tunguska.In this show was a
> section on how the scientists determined the hight and
> angle. They flew a series of charges over a forest of
> pins on a test board and recorded the shapes left by
> the explosions.They continued this until they came up
> with the butterfly pattern of tunguska.I am confidante
> the shape of my dry lake will be in this data.I hope
> you can help me.Contact me at
> jiujitsu11_at_yahoo.com.Thank you,Alvie Roach
>
Received on Mon 19 Aug 2002 01:45:56 AM PDT