Hola Sterling, and thank you for the gracious email. Hopefully this gas
cooled down; I won't go for another round on this one now, I promise. I pray
the
tektite debate won't continue until after we are dust, but in some places,
probably you are dead right there.
I've always thought that one
: Mike Fowler [EMAIL PROTECTED]
Sent: Saturday, March 04, 2006 11:11 AM
Subject: [meteorite-list] Largest Crater in the Sahara Desert and LDG
This is actually a more general point: there are lots and lots of
impact
craters but very few tektite producing ones; why?
Sterling K. Webb
Why not very
Sterling W. writes:
Doug, the actual language Kroeberl uses
is that the F/B ratio of tektites should tend
toward 1.0. This is Professional Science
Speak for too complex to model exactly,
but most of the cows ought to stampede
in this direction...
Hola Sterling, I asked you where you got the
] Largest Crater in the Sahara Desert and LDG
Sterling W. writes:
Doug, the actual language Kroeberl uses
is that the F/B ratio of tektites should tend
toward 1.0. This is Professional Science
Speak for too complex to model exactly,
but most of the cows ought to stampede
in this direction...
Hola
Sterling W. writes:
I don't know the values for the Nubia Sandstone,
but the range of sandstones is fluorine 180 to 450
ppm and boron about 10 to 85 ppm. The figures
for LDG is fluorine 7 ppm and boron 7 ppm, so
you see how the ratios shift as the content drops.
As the temperature rises
@meteoritecentral.com
Sent: Sunday, March 05, 2006 2:34 AM
Subject: Re: [meteorite-list] Largest Crater in the Sahara Desert and LDG
Sterling W. writes:
I don't know the values for the Nubia Sandstone,
but the range of sandstones is fluorine 180 to 450
ppm and boron about 10 to 85 ppm. The figures
for LDG
Sterling:
Sounds good to me (though I study big rocks that you can see with a
telescope). It sounds like it is time for me to start reading up on tektites
too!
As a novice, would you basically say that tektites come from volatilized
material that has recondensed while an impactite derives
-
From: Norm Lehrman [EMAIL PROTECTED]
To: Larry Lebofsky [EMAIL PROTECTED]; Sterling K. Webb
[EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED];
Meteorite-list@meteoritecentral.com
Sent: Sunday, March 05, 2006 9:13 AM
Subject: Re: [meteorite-list] Largest Crater
PROTECTED];
Meteorite-list@meteoritecentral.com
Sent: Sunday, March 05, 2006 9:13 AM
Subject: Re: [meteorite-list] Largest Crater in the Sahara Desert and LDG
All,
Thanks for the fabulous discussion. I had to take
time out from the discourse to wash, size-sort, cull,
and count 10,000 tektites
-list] Largest Crater in the Sahara Desert and LDG
Hola Norm, so it seems we actually agree on most of the points, including
the
most important one: the subjectivity of the definition. You are just
wanting
to be more liberal...and me more stoodgy...I wasn't dodging the layered
tektite issue when
This is actually a more general point: there are lots and lots of
impact
craters but very few tektite producing ones; why?
Sterling K. Webb
Why not very high velocity comet impacts, at a near vertical angle.
Maximum cometary velocities would be about 10 times more than average
Sterling W. writes:
Crustal rocks have 5 or 10 times
more fluorine than boron. Tektites should have a ratio of 1.0,
indicating that they were heated to temperatures high enough
to drive off most of the fluorine and leave the two halogens
at identical levels (however low the absolute amount),
-
- Original Message -
From: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]; [EMAIL PROTECTED];
[EMAIL PROTECTED]; Meteorite-list@meteoritecentral.com
Sent: Saturday, March 04, 2006 4:05 PM
Subject: Re: [meteorite-list] Largest Crater in the Sahara Desert and LDG
Sterling W
Hi Ron and List,
Like so many others, I was eagerly flying over the lines in search of
a hint to LDG (Libyan Desert Glass),and, there it is (of course ;-):
since its shape points to an origin of extraterrestrial impact, it will likely
prove to
be the event responsible for the extensive field
Bernd list,
This is indeed exciting, and may finally justify LDG
being recognized as a true tektite rather than a
simple impactite.
Although the article doesn't give us much for location
beyond at the northern tip of the Gilf Kebir region,
that's close enough, as the LDG strewn field is
Hi List,
My two cents worth: Tektites are blasted into space and then
return. Horizontal flow, blast , ejection or whatever, would not a
tektite make, at least in the classical sense.
Mike Fowler
Where is the dividing line between impactite and
tektite? I'd like to hear what others
Norm L. writes:
Where is the dividing line between impactite and
tektite? I'd like to hear what others may understand,
but my impression is that it fundamentally hinges on
distance the glassy material is ejected from the
crater. Material found only in and immediately around
the source
Doug,
Good points all, but if you want to raise the
water/purity issue, you can't dodge the Muong Nong
issue. (The best answer is that they shouldn't be
called tektites, BUT, they ARE so called by all
authorities).
With LDG, it can be reasonably argued that
flight-related morphology has been
Hola Norm, so it seems we actually agree on most of the points, including the
most important one: the subjectivity of the definition. You are just wanting
to be more liberal...and me more stoodgy...I wasn't dodging the layered
tektite issue when I said not to bring it up (which you
Doug,
I do enjoy your contributions. Always stimulating.
I have no fundamental disagreements. Just a few
hair-splitting points.
Re: the partial pressures in Australasian bubbles. It
has been argued that our numbers are bogus. As
atmospheric water is absorbed into the hydrating
tektite
From: Norm Lehrman [EMAIL PROTECTED]
To: [EMAIL PROTECTED],
[EMAIL PROTECTED],Meteorite-list@meteoritecentral.com
Subject: Re: [meteorite-list] Largest Crater in the Sahara Desert and LDG
Date: Fri, 3 Mar 2006 18:23:29 -0800 (PST)
Doug,
I do enjoy your contributions. Always stimulating.
I have
Perhaps, rather than falling like a dead rat into the division between
tektites and impactites, LDG is an indicator of more of a continuous
spectrum. We already admit that there are anomalies where Muong Nong
tektites and some aspects of australites don't fit comfortably within
tektite
22 matches
Mail list logo
