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DIVNOE A BRACHINITE?

Hello, everybody out there,

A) In the February 1998 issue of Joel's METEORITE! magazine (page 4),
Jim Phillips from Charleston, South Carolina, lists  D i v n o e  as a
brachinite. Can someone support this view?

The authors of the following papers in Meteoritics are reluctant to
include  Divnoe with the brachinites:

1) Yu.A.Shukolyukov et al. (1995) Noble gases and strontium isotopes in
the unique meteorite Divnoe (Meteoritics 30-6, 1995, 654-660,
Introduction):

In its Fe/Si ratio the Divnoe meteorite is analogous to H and L
chondrites but its Mg/Si and Al/Si ratios are more typical of
olivine-rich, primitive achondrites such as brachinites. However, Divnoe
differs from the latter in having higher troilite and metal contents. In
other words, the Divnoe meteorite is evidently anomalous in its
major-element abundances. The REE pattern and abundances in Divnoe are
also essentially distinct from those of most chondrites and achondrites.
However, there are some resemblances to unbrecciated diogenites and
lunar dunites (i.e. the Divnoe meteorite may be related to the
differentiated meteorites of restite and cumulate genesis rather than to
the 'primitive achondrites', Petaev et al., 1994). The isotopic
composition of O in Divnoe is close to that of the HED-meteorites,
winonaites and brachinites (Petaev et al., 1994).

2) O. Bogdanovski et al. (1997) MANGANESE-53/CHROMIUM-53 ISOTOPE SYSTEM
IN THE DIVNOE METEORITE (Meteoritics 32-4, 1997, A016):

The mineral composition of Divnoe is similar to that of ordinary
chondrites, but it has an achondritic texture and belongs to the
specific meteorite group of primitive achondrites ...
The composition of Divnoe could be derived from a chondritic source by
partial melting, followed by crystallization of the partial melt, and
removal of the still-liquid portion of the partial melt. The
coarse-grained lithology represents the residue of partial melting, and
the poikilitic patches are a portion of partial melt that crystallized
in situ ...


B) In the same issue, Jim Phillips writes that Reid 013 is synonymous
with Window Butte, Nova 003 and Kent.

1) How can Window Butte, "a new 187-g find (1991) from Utah" be
synonymous with Window Butte? - (or am I having a language barrier
problem?)

2) There is no  K E N T  in my database. Does anyone know more about
that?


C) There is also an article in the same issue about D.S. Futrell's visit
to the Old Woman meteorite. This reminded me of an article that appeared
in S&T in 1977: Sky & Telescope, Vol. 54-3, Sep 1977, p. 192: OLD WOMAN
METEORITE

A three-ton meteorite recently discovered in the Old Woman Mountains of
California is the second largest ever found in the United States,
outranked only by the 16-ton Willamette, Oregon, meteorite known since
1902.
The Old Woman fall is a mass of nickel-iron weighing 6,080 pounds (2,758
kilograms) and measuring 4-by-3-by-2 1/2 feet (1.2-by-0.9-by-0.8
meters),according to newspaper accounts. It fell, presumably several
centuries ago, in an inaccessible desert area 170 miles east of Los
Angeles.There it was spotted in March, 1976, by three gold prospectors.
They sent chips to the Griffith Observatory and the University of
California at Los Angeles, where the meteoritic nature of the object was
confirmed.
Word of the discovery reached Roy S. Clarke, curator of meteorites at
the Smithsonian Institution in Washington, D.C. The U.S. Bureau of Land
Management determined that the find had been made on federal land, and
gave possession of the meteorite to the Smithsonian.
The nickel-iron mass lay wedged among boulders up a dry wash between two
mountain slopes.  On June 17th, the meteorite was airlifted from this
spot by U.S. Marine Corps helicopter, which carried it seven miles to
the nearest road. Until the end of June, the Old Woman meteorite was on
public display at Riverside, California, and then it was sent to the
Smithsonian Institution for scientific study.

D) Here is some information from my database with regard to the Old
Woman:

Old Woman, Octahedrite, coarsest (10mm), IIB
U.S.A., California, Old Woman Mountain
34° 28' N / 115° 14' W / Find 1976, Total 2753 kg
2753kg, Washington, U.S. Nat. Mus. -  Specimen,  Los Angeles, Univ. of
California

A large single mass of 2753kg was found on the western slopes of the Old
Woman Mountains, Meteor. Bull., 1978, (55), Meteoritics, 1978, 13,
p.344. Brief report, J.T. Wasson and J. Willis, Meteoritics, 1976, 11,
p.386 Classification and analysis, 5.71 %Ni, 58.5 ppm Ga, 190 ppm Ge,
0.80 ppm Ir, A. Kracher et al., GCA, 1980, 44, p.773.

E) And here is a passage from Meteoritics about the 'Old Lady':

B. Lavielle et al. (1995) Depth-dependent concentrations of
berryllium-10, aluminum-26, chlorine-36, HEc, NEc and ARc in the Old
Woman iron meteorite (abs. Meteoritics 30-5, 1995, p.534):

Concentrations of 4He, 21Ne, and 38Ar in aliquots of the samples were
determined by conventional mass spectrometry using an isotopic dilution
method. The ratio 3He/4He appears to be almost constant with a value of
0.12 - 0.13. This is about half the value generally observed in iron
meteorites. Similar low ratios have been previously observed in some
irons and in chondritic metal, and reflect diffusion losses of 3H [2,3].
The ratios 4He 38Ar, 4He/21Ne, and 36Ar/38Ar are similar to those
observed in iron meteorites, indicating no significant losses of 4He.
The measured ratio S = 4He/21Ne, which represents one of the best
indicators of shielding depth in iron meteorites, varies from 310 to 375
in samples from the slice. By using this as a shielding parameter,
profiles were obtained for the different nuclides investigated in this
work. Systematic decreases from the surface to the center of the
meteorite are observed, and the center of the meteoroid can be
determined. As expected from nuclear systematics, the ratio 36Cl/36Ar is
almost constant. The ratio 36Cl/10Be is relatively constant with a mean
value of 4.7, indicating that the t e r r e s t r i a l  a g e  o f  Old
Woman is probably l e s s   t h a n  50,000 yr.

References:
[1] Nishiizumi K. et al.(1991) Meteoritics 26, 379-380
[2] Schultz L. (1967) EPSL-2, 87-89
[3] Graf T. et al. (1995) Chlorine-36/argon-36 exposure ages of
chondritic metals (Meteoritics 30-5, 1995, 512).

Regards, Bernd