Sample Petrographic Description
Sample Number | MIL 07613 |
Newsletter | 32,1 |
Location | Miller Range |
Field Number | 18795 |
Dimensions (cm) | 2.0 x 2.0 x 1.0 |
Weight (g) | 4.56 |
Original Classification | Diogenite |
Pairing | MIL 07003; MIL 07613; MIL 090105; MIL 090106; MIL 090107; MIL 090112; MIL 090159; MIL 090220; MIL 090221; MIL 090291; MIL 11099; MIL 11197; MIL 11198; MIL 11199; MIL 11201; MIL 11202; MIL 11204; MIL 11205; |
Mineral Composition (%Fa & %Fs) | |
Ferrosilite (mol%): 14-36 | |
Weathering | |
B | |
Fracturing | |
A/B | |
Macroscopic Description - Kathleen McBride | |
The exterior has 40% brown/black fusion crust. The interior matrix is fine grained, tan in color and has black inclusions. | |
Thin Section Description (,3) - Tim McCoy, Linda Welzenbach | |
The section consists of an unbrecciated mass 2-5 mm orthopyroxene grains which interfinger at grain boundaries. Blebby diopside lamellae are common within the orthopyroxene. Large (several hundred microns) chromites are common at grain boundaries. Orthopyroxene has a composition of Fs36Wo2, diopside is Fs14Wo45 and plagioclase is An92. The Fe/Mn ratio of the pyroxene is ~30. The meteorite is likely a diogenite, although the texture is unlike typical diogenites and the pyroxene composition more FeO-rich than typical of diogenites. | |
Oxygen Isotopic Composition - Doug Rumble, Geophysical Laboratory, Carnegie Institution of Washington | |
δ17O = 1.62, δ18O =3.57, Δ17O = -0.260 |
|
Notes | |
MIL 07003, MIL 07613 (4 – 090105, 090106, 090107), MIL 090159 (3 – 090220, 090221), MIL 090112 (7 – 090291, 11099, 11201, 11202, 11204, 11205), MIL 11197, MIL 11198, and MIL 11199. Combination of these three diogenite pairing groups as well as four previously unpaired masses to form a new large 18 member pairing group of diogenites MIL 07003; based on terrestrial ages, compositions, find locations, and petrographic textures. Pairing updated in AMN 47,1. |
Antarctic Meteorite Images for Sample MIL 07613 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample MIL 07613 | ||||
Thin Section Photo(s) : | ||||
References for Sample MIL07613 | |
Mittlefehldt, D. W., 2015, Asteroid (4) Vesta: I. The howardite-eucrite-diogenite (HED) clan of meteorites. Chemie der Erde - Geochemistry, 75 Issue 2, Jun-15, 155-183, ISSN 0009-2819, http://dx.doi.org/10.1016/j.chemer.2014.08.002. |