Re: [asa] meteorites in the geologic column

From: Randy Isaac <randyisaac@comcast.net>
Date: Mon Sep 22 2008 - 10:01:49 EDT

Very helpful, George. Thank you.
A summary of what I learned is:

1. Most meteors disintegrate in the atmosphere--the ones that survive to hit the ground are usually iron or iron-rich, though a few stony ones also survive.
2. The iron-rich meteorites quickly rust away, generally in a few dozen years, unless they land in a desert or in ice.
3. A few rare stony meteorites have been found that were "fossilized" in the sense of the minerals having been replaced by terrestrial minerals but the shell still intact and discernible. Two of them date to 450 and 480 million years. Very rare.
4. The oldest intact meteorite is the one you point out that was found in Oklahoma and is 110 million years
5. Looking for remnants of meteorites is indeed like the proverbial needle in a haystack: "every million short tons of coal should yield about 300 grams of recoverable magnetic macro-meteorites". Isn't that at or below the ppb range?

Net: not a very good way to determine the age of the earth.

Randy
  ----- Original Message -----
  From: George Cooper
  To: asa@calvin.edu
  Sent: Monday, September 22, 2008 8:44 AM
  Subject: RE: [asa] meteorites in the geologic column

  [I see my rushed response didn't answer your question. Sorry.]

   

  Here is a paper addressing meteorites found within the Ordovician strata in Sweeden:

  http://adsabs.harvard.edu/abs/1996E&PSL.145...31S

   

  This site gives further information:

  http://www.meteorite.fr/en/basics/charts.htm

   

  "The oldest intact meteorite [based on time on Earth] is the Lake Murray iron. A single mass with a thick iron-shale was found in a gully in Oklahoma, USA, in 1933. The meteorite was imbedded in some Antler Sandstone dating from the Lower Cretaceous, suggesting that Lake Murray landed in a near-shore, shallow sea, while these beds were being deposited about 110 million years ago."

   

  "Most meteorites weather away quite quickly in the oxidizing environment of the Earth, while some meteorites may literally be observed as they rust away. However, other meteorites fell at more fortuitous locations and were preserved until this day, e.g. in the ice fields of Antarctica and in the hot deserts of Africa. Some of them have been preserved for as long as 40,000 years or more. Indeed, there are some meteorites found to be much older still - those that have been preserved in sediments or in other geologic strata conducive to preservation, often referred to as "fossil meteorites"."

   

  [I respect John McArthur on other things.]

   

  "Coope"

   

   

   

  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On Behalf Of Randy Isaac
  Sent: Friday, September 19, 2008 2:47 PM
  To: asa@calvin.edu
  Subject: [asa] meteorites in the geologic column

   

  This morning as I was scanning radio stations in the car, I came across John MacArthur's "Grace to You" program.

  http://www.oneplace.com/ministries/Grace_to_You/

  Since Sept. 8 he has been doing a series on creation and today he was talking about Day 3. No, I haven't gone back to listen to all those segments. Reading the blurbs is enough of an indication of his message.

   

  Today he brought up a YEC claim that I hadn't investigated myself and I wondered if any of you had. His point was that if the meteor flux was essentially constant over the geologic periods, then meteorites should be found throughout the historical sedimentary rocks. Yet, he says, no meteorites have ever been found other than at the surface. Hence, there was no extended age of the universe prior to the flood when all the sedimentary rock was deposited.

   

  What is the actual distribution of meteorites with respect to location in the strata?

   

  Randy

   

   

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Received on Mon Sep 22 10:03:23 2008

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