[meteorite-list] Olivine Diogenite Naming

From: Adam Hupe <adamhupe_at_meteoritecentral.com>
Date: Thu Apr 22 10:21:03 2004
Message-ID: <02e201c3481a$ef090080$b4dbe60c_at_attbi.com>

Dear John and List,

These are the very points scientists are working on. Fortunately all of the
current Olivine Diogenites are fairly rich in Olivine and differ noticeable
from the rest of the HEDO group. The FeO/MnO ratios differ from that of
Diogenites, as well. They are heterogeneous complicating the ratio count so
if a small type specimen is deposited there could be some variability so the
final definition will have to take this into account. Like all the other
HEDO classifications I am sure there will be ranges that have to be adhered
to or else we will end up with transitional types. We will keep you up to
date on this very dynamic situation. Expect to hear a lot more soon.

All the best,

Adam


----- Original Message -----
From: <j.divelbiss_at_att.net>
To: "Adam Hupe" <adamhupe_at_comcast.net>
Cc: <meteorite-list_at_meteoritecentral.com>
Sent: Friday, July 11, 2003 7:06 PM
Subject: Re: [meteorite-list] Olivine Diogenite Naming


> Adam and Greg,
>
> Thank you for the response and congratulations on being part of making
> meteorite history. Sorry if I seem to be trying "gum up the works". I do
that
> more than I should sometimes. I'll continue this discussion with one more
set
> of thoughts.
>
> My personal obsession (as a novice) with earth's gabbroic rocks has me
quite
> interested in this material and how it relates to similar earthly and
> meteorite (achondrite) materials. Harzburgite, as I understand it, is 40%
> olivine or greater until we call it a Dunite, while Olivine
Orthopyroxenite is
> less than 40 % olivine, down to about 10 % or so. And then there is plain
old
> Orthopyroxenite that is 10 % or less in olivine, and covers what we call
> Diogenites for meteorites.
>
> So, as far as meteorites go, we have the upper level of "lower crust" in
> Diogenites, and much deeper material in what we now call Olivine
Diogneites.
> My question now is, "I wonder how far down in % of olivine (ie. 10, 20,
30%)
> will the description go to be classified as an Olivine Diogenite...and
could
> there be a need for a classification between Diogenite and Olivine
> Diogenite?", if and when we find something in between the present examples
> that are classified.
>
>
> Regards,
>
> Crusty John
>
>
>
> > Dear John and List Members,
> >
> > There is not much to worry about as far as confusing a real "Olivine
> > Diogenite" with a standard Diogenite if this is what you are asking. A
real
> > Olivine Diogenite is a Harzburgitic Peridotite not an Orthopyroxenite so
any
> > scientists should be able to distinguish between the two. I only
mentioned
> > the real McCoy thing because somebody was trying to pass off a common
> > diogenite with an accessory amount of olivine for $500.00 a gram
wholesale
> > claiming it to be a peridotite. Here is a good link describing the real
> > McCoys which compares the four real "Olivine Diogenites" in existence at
> > that time, now there is five:
> >
> > http://www.lpi.usra.edu/meetings/lpsc2003/pdf/1502.pdf
> >
> > Note the ratio chart. This would serve to easily tell the difference.
In
> > my opinion the word "Diogenite" should not be used to describe this
rarest
> > of classes because it is not really a diogenite because it comes from
the
> > mantle. We believe at this point changing the name would add even more
> > confusion. Hey, this is a history making class, time to celebrate!
> >
> > All the best,
> >
> > Adam
> >
> >
> >
> > ----- Original Message -----
> > From: <j.divelbiss_at_att.net>
> > To: "Adam Hupe" <adamhupe_at_comcast.net>
> > Cc: <meteorite-list_at_meteoritecentral.com>
> > Sent: Friday, July 11, 2003 4:45 PM
> > Subject: Re: [meteorite-list] Olivine Diogenite Naming
> >
> >
> > > Adam,
> > >
> > > The naming logic seems reasonable.
> > >
> > > However, does this mean we could one day have an olivine-rich
Diogenite
> > that
> > > is not an Olivine Diogenite?
> > >
> > > Without getting into to much detail, what general criteria will it
take to
> > be
> > > called an Olivine Diogenite?
> > >
> > > Regards,
> > >
> > > John
> > > >
> >
> >
> > ______________________________________________
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> > Meteorite-list_at_meteoritecentral.com
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Received on Fri 11 Jul 2003 10:11:40 PM PDT