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Hi Doug and List,
I also wonder about another point on meteorite
falls... Since I started hunting them, I thought that they can fall anywhere,
the location of their landing place depending on their orbit around the sun and
the angle they meet the Earth with. Is that right or are there any areas on our
planet where they get more "attracted" ?
There have been more finds in Antarctic than
anywhere else, but I guess that it's simply because people have been searching
for them there for a longer time, but can it be for another reason ? Has the
magnetic field linking the poles any effect (like for boreal auroras) ?
...
I'm not a scientist and maybe my question sounds
strange, but should anybody have a clear and easy to understand explanation,
thanks in advance for sending it, just for my knowledge.
Kind regards
----- Original Message -----
Sent: Tuesday, December 16, 2003 5:49
AM
Subject: Re: [meteorite-list] Dry Lake
Stewnfields??
Hi John, I think if we get back to basic
definitions, a strewn field is an ellipsoid shape caused by a mid air
explosion raining down material, as far as I understand. What happens
afterwards to the material is irrelevant. And the strewn field is a
geometric representation fitted to the fall in practice, not the actual
individual stones. If some gets moved, picked clean, the boundaries of
the strewn field can't change, from their original definition.
Perhaps
some of the hunters among us will not see it that way...as strewn tends to
bring a connotation of waltzing in and cleaning up. And an empty strewn
field sounds odd...
So I would think that the technical "set one
straight answer" you want is that: Mathematically it takes at least four
border points to make an ellipse, but to actually be able to fit one with any
confidence in an area, you need plenty more, to fill in the area. A neat
statistical definition seems impractical, so it will come down top the field
researcher's opinion. If the one who did the research wants to call it a
strewn field and their is evidence for a mid air explosion...then we should
have one. And if there are a few rocks...in the desert, or in Chicago,
and the principal investigator(s) don't feel there is enough for an ellipse,
then its not, because they say so. An it is a good assumption if we
happen upon an old scattered field, we can say...this might be a strewn field,
but lacking a good cause-effect ellipse explanation there can't be a right
answer for lack of data. In the end one can probably collect opinions on
this until blue in the face...and who calls what a what...but for
what?
Strewn fields are simply human categories so we can make sense
out of natural events that don't have to conform to our neat, ways of
nomenclature. Just like the concept of a species or a race in
biology. You know an obvious one when you see it...but when you start
taking it as gospel and look at the limits of the definition, the whole think
breaks down, and mass consensus isn't reached...plus air resistance already
distorts a strewn field to a researcher. So there has got to be a little
eyeballing going on since tiny particles don't fall nicely. If it looks
like a strewn field, (tastes like one), ...
Sipping my hot
chocolate...Saludos
Doug Dawn
Mexico
En un mensaje con fecha
12/15/2003 10:17:15 PM Mexico Standard Time, [EMAIL PROTECTED]
escribe:
To Rob, Bob, Adam, and others:
Recent finds from
the Nevada dry lakes were grouped in a small area within a
dry lake. The
finding of three apparent pieces from same fall created a
description by
Adam that these finds might constitute a new strewnfield.
Questions/observations in regards to desert strewnfields.
1.
Obvious groupings of fallen masses would make the likelihood of the area
being a meteorite stewnfield. Do multiple finds in desert locale usually
get
described as a stewnfield?
2. Does the fact that many rocks
get moved around in these environments take
the strewnfield idea down a
notch with rocks being scattered?...or does their
proximity within the
bounds of normal surface movements qualify them to be
still within the
original strewnfield?
3. Is the idea of stating a location has a new
strewnfield more about this
location being a new place to find more than
one meteorite of the same
apparent fall?...and not so much about the
actual fall characteristics?
I guess I'm just curious about the use
of word strewnfield in this case?
Yearning to be set
straight,
John
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