[meteorite-list] Canyon Diablo & nomenclature...

From: Greg Redfern <gredfern_at_meteoritecentral.com>
Date: Sun May 15 12:41:49 2005
Message-ID: <000b01c5596d$04146540$110110ac_at_homeqmkddyxspr>

Dear List,

  Jeff may have this volume in his literature but I thought it might be
worth mentioning. "Coon Mountain Controversies" by Hoyt & published by
University of Arizona is THE reference volume on Meteor Crater.

  I also think it is worth mentioning that Dr. Shoemaker's USGS paper on
"Impact Mechanics at Meteor Crater, Arizona" is the reference Mark spoke of.


All the best,

Greg

Greg Redfern
NASA JPL Solar System Ambassador
http://www2.jpl.nasa.gov/ambassador/index.html
What's Up: The Space Place
http://www.wtopnews.com/index.php?nid=421


-----Original Message-----
From: meteorite-list-bounces_at_meteoritecentral.com
[mailto:meteorite-list-bounces_at_meteoritecentral.com] On Behalf Of Jeff
Grossman
Sent: Friday, May 13, 2005 10:02 AM
To: meteorite-list_at_meteoritecentral.com
Subject: Re: [meteorite-list] Canyon Diablo & nomenclature...

Here's what I could learn in a brief review of literature I have. Others
know much more about this than I do.

GK Gilbert published a paper in Science, "The Origin of Hypotheses,
Illustrated by the Discussion of a Topographic Problem", Science, Vol. 3,
No. 53. (Jan. 3, 1896), pp. 1-13. This was the text of his presidential
address to the Geological Society of Washington in 1895 (I hope my
presidential address to GSW last year better stands the test of time).

In this paper, he tests his own hypothesis that the crater formed by the
impact of a "star". After a two weeks of field work involving topographic
measurements and magnetic surveys, he could not find evidence to support
his hypothesis, which he thought predicted there would be a large, buried,
magnetic mass beneath the crater: there was no large magnetic anomaly, and
the volume of ejecta perfectly matched to volume of the hole, leaving no
room for a 1500-foot diameter buried spherical object. (He does leave open
the possibility that the crater could still have been formed by a
"plum-pudding" object with iron masses embedded in stone, which is really
interesting because that's now one of the prevailing ideas about how IAB
irons really did form!). Anyway, at this point, he abandoned his intuition
and went looking for alternative ideas, which turned out not to be very
good.

Although Gilbert couldn't find the evidence to support his hypothesis, the
impact idea was his. In 1905, Barringer and Tilghman published back to
back papers in the Proc. Acad. Nat. Sci. Phila., refuting Gilbert's
fall-back explanation that the crater was due to a steam explosion. They
made lots of good observations consistent with impact, but both of them
still accepted Gilbert's idea that there had to be a buried meteorite if it
was an impact crater. They just weren't willing to overlook all the other
evidence that pointed to impact, as Gilbert did.

It wasn't until 1907 that Herman Fairchild published (GSA Bull. 18,
493-504, a paper read before the Society on 12/29/1906) the idea that the
projectile might be travelling very fast and therefore only had to be a few
100 feet across. This made it less likely that a buried mass would be
found, and so took care of Gilbert's big objection.

Fairchild also talked about renaming the crater "Meteor
Crater." Interestingly, he notes that "for some time the U. S. Post Office
located near Mr Holsinger's camp [near the crater rim] with the name
Meteor, Arizona, gives an official standing to the word [meteor]." So
somebody was using this name before Fairchild.

jeff

At 07:37 AM 5/13/2005, MARK BOSTICK wrote:
>Hello Ron and list,
>
>Ron noted, "The name "Meteor Crater" was first formally proposed...on
>December 29, 1906...."
>
>Barringer was calling it Coon Mountain at this time, so the reference
>appears to be accurate. My question was however when was the crater
>officially scientifically recognized as a meteorite crater. But I guess
>there isn't a clear answer. The USGS was claiming the crater to be a
>steam blowout in 1906.
>
>For locals, it was pre-1901, when written reference of the crater starts.
>
>Does anyone know if the USGS wrote any crater origin papers on the
>structure before Shoemaker?
>
>Clear Skies,
>Mark
>
>
>______________________________________________
>Meteorite-list mailing list
>Meteorite-list_at_meteoritecentral.com
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Received on Sun 15 May 2005 12:42:00 PM PDT