[meteorite-list] R Chondrites and Magnetism

From: Tom Knudson <peregrineflier_at_meteoritecentral.com>
Date: Tue May 31 15:01:02 2005
Message-ID: <00d001c56613$16086d70$2d107918_at_Michelle>

"extensive aqueous alteration on the R parent body"

Water in space? That sounds like a whole new subject! : )

Thanks, Tom
peregrineflier <><

----- Original Message -----
From: <bernd.pauli_at_paulinet.de>
To: <Meteorite-list_at_meteoritecentral.com>
Sent: Tuesday, May 31, 2005 11:48 AM
Subject: [meteorite-list] R Chondrites and Magnetism


> Tom concluded:
>
> > So, most R's have enough metal to be
> > attracted to a powerful enough magnet
>
> Careful, please. I'd like to add the little word "just",
> leave out the word "most" and replace it by "some":
>
> > Some R's have j u s t enough metal to be
> > attracted to a powerful enough magnet ...
>
> This sounds better because almost all the iron is oxidized and
> also FeNi (nickel-iron) is extremely rare (only some tens of parts
> per million!)
>
> In his Cambridge Encyclopedia, O.R. Norton writes on p. 116:
>
> "There is almost no free iron metal (a few grains here and there) ..."
>
> > ... if I can find out why R's have so little metal.
>
> Oxidation (water was the oxidizing agent):
>
> Step 1: extensive aqueous alteration on the R parent body
> Step 2: dehydration (removal of water) + thermal metamorphism
>
>
> Best wishes,
>
> Bernd
>
> ______________________________________________
> Meteorite-list mailing list
> Meteorite-list_at_meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Anti-Virus.
> Version: 7.0.322 / Virus Database: 267.3.2 - Release Date: 5/31/2005
>
>
Received on Tue 31 May 2005 03:01:00 PM PDT