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Lunar Meteorite: Queen Alexandra Range (QUE) 93069 & 94269 (paired stones)Antarctica |
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| QUE
93069 (left) and QUE 94269 (right) are two different pieces of a single
meteorite. They were found 1 year apart. Like QUE
94281, the fusion crust on QUE93069/94269 is strikingly vesicular (it
has bubbles) because both meteorites are regolith
breccias (from NASA photos S94-033320 and S96-00385). The cube
is 1 cm square. |
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| QUE
93069 in the field (photo by Ralph Harvey). |
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| On the left we
see the same side of QUE 93069 in the lab as in the field; on the left is
QUE 94269. On these broken surfaces many light-colored clasts are
visible. In this regard, the meteorite resembles many kinds of terrestrial
sedimentary rocks. Notice, however, that there is no preferred orientation
of the clasts and no hint of layering or linear features, as in many terrestrial
sedimentary rocks. There is no mechanism for making layered rocks
on the Moon (no water, no wind). Note also that the clasts vary in
size. In many terrestrial sedimentary rocks, the clasts are all about
the same size because they have been size-sorted when they were deposited
in a sea or ocean (coarser grained suspended material carried to the sea
by rivers gets deposited closer to shore than fine-grained material).
Finally, notice that many of the clasts are angular, although a few are
rounded. Meteorioid impacts tend to make angular rock fragments. Rounded
fragments are typical of terrestrial clastic materials that are abraded
by grinding against each other in an aqueous environment like a seashore
or river. (from NASA photos S94-033316 and S95-14250) |
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| Listed in The
Meteoritical Bulletin, No. 79, Meteoritics & Planetary Science
31, A161-A174 (1996) from Antarctic Meteorite Newsletter, vol. 17, No. 2, 1994 (PDF p. 3) QUE 93069Location: Queen Alexandra RangeDimensions (cm): 5.0 x 2.2 x 2.3 Weight (g): 21.4 Weathering: A/B Fracturing: B Meteorite Type: Lunar-anorth. breccia Macroscopic Description: Cecilia Satterwhite and Marilyn LindstromThe overall shape of this lunar meteorite is approximately one third of a flat ovoid. Thick gray-green frothy fusion crust covers the top while thin granular medium olive green-brown fusion crust covers the bottom. The north face is a fractured surface with exposed interior matrix and abundant fractures. This surface consists of black matrix with abundant millimeter sized white/ gray clasts. Some clasts have weathered to a yellowish color. One gray clast is visible in a fracture. Cleaving this meteorite revealed a lighter gray matrix with small clasts of various sizes. One white, friable clast (3 x 2 mm) is directly below the fusion crust. An area 2 x 2 mm near this clast has a uniform, dusty-gray appearance with an indistinguish-able border. All of the clasts present are small and friable and unfortunately may not be extractable.Thin Section (,5) Description: Brian MasonThe section shows a microbreccia of small plagioclase grains and granular clasts, up to 0.6 mm across, in a translucent to semi-opaque brown glassy matrix; colorless vesicular fusion crust is present on one edge. There is one large clast, 2.4 x 3.6 mm, of pale brown partly devitrified glass. Traces of metallic iron, as irregular grains up to 40 microns, are present. Microprobe analyses show that the plagioclase is almost pure anorthite (Na2O 0.3-0.4%, K2O less than 0.1%). The composition of the fusion crust, probably a reasonable approximation for the bulk meteorite, is (weight percent): SiO2 44, Al2O3 27, FeO 4.4, MgO 4.5, CaO 16, Na2O 0.32, K2O less than 0.1 %, TiO2 0.24, MnO 0.10. The FeO : MnO ratio is high, 44-75, characteristic of lunar material. The meteorite is an anorthositic microbreccia, presumably of lunar origin. In thin section, it is very similar to MAC 88105 (Antarctic Meteorite Newsletter 12(2), 1989). |
| Listed in The
Meteoritical Bulletin, No. 79, Meteoritics & Planetary Science
31, A161-A174 (1996) from Antarctic Meteorite Newsletter, vol. 18, No. 2, 1995 QUE 94269Location: Queen Alexandra RangeDimensions (cm): 1.9 x 1.4 x 1.3 Weight (g): 3.2 Meteorite Type: Lunar-Anorthositic Breccia Macroscopic Description: Roberta ScoreThis lunar meteorite is identical to QUE93069 and would probably fit together if QUE93069 was still in one piece. One side of this flat stone has thick gray-green, frothy fusion crust. The other side has thin, weathered, dull green-brown fusion crust. A fractured surface reveals the interior matrix which is dark gray to black with abundant inclusions. The largest inclusion is white and measures 1.0 x 0.2 cm. The newly exposed interior surface has a lighter gray-colored matrix and abundant white and gray clasts. One white clast measures 0.4 x 0.2 cm. Other inclusions present include fine-grained, buff-colored clasts, several brecciated gray clasts, and smaller white clasts. Many clasts have weathered to a yellowish color. As in QUE93069, most of the clasts are small and friable and, unfortunately, are not extractable.Thin Section (,5 and ,7) Description: Brian MasonThe sections show a microbreccia of granular clasts, up to 1.5 mm across, and small plagioclase grains, in a translucent to semi-opaque brown glassy matrix; one grain of metallic iron, 0.3 mm across, was noted. Most of the plagioclase is almost pure anorthite (Na2O 0.3-0.5%, K2O less than 0.1%), with a few grains with higher Na2O, up to 3.2%. QUE94269,7 has a 3 mm clast of subequal amounts of plagioclase and pyroxene; the plagioclase is anorthite (Na2O 0.3-0.5%), the pyroxene ranges from Wo5Fs39 to Wo34Fs22 with fairly uniform En content. This specimen is a lunar meteorite, very similar to QUE93069 (Antarctic Meteorite Newsletter 17(2), 1994), with which it is certainly paired. |
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