Sample Petrographic Description
Sample Number | MIL 07003 |
Newsletter | 31,2 |
Location | Miller Range |
Field Number | 17561 |
Dimensions (cm) | 8.0 x 4.5 x 5.0 |
Weight (g) | 291.95 |
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%): 27-34 | |
Weathering | |
B | |
Fracturing | |
A/B | |
Macroscopic Description - Kathleen McBride | |
50% of the exterior is covered by dark brown black fusion crust with polygonal fractures. The exposed interior is tan and fractured. The tan interior with yellowish brown patches mars the surface. Black, glassy veins and inclusions and a few white clasts are present. | |
Thin Section Description (,4) - Tim McCoy, Linda Welzenbach | |
The section shows a groundmass of coarse (up to 2 mm) comminuted pyroxene with interstitial plagioclase and SiO2. Orthopyroxene has a composition of Fs27-34 Wo1-4 and plagioclase is An85-89Or1 . The Fe/Mn ratio of the pyroxene is ~30. The meteorite is a diogenite, although the pyroxene is on the FeO-rich end of diogenites towards cumulate eucrites. | |
Oxygen Isotopic Composition - Z. Sharp, University of New Mexico | |
Oxygen isotopic analyses of two splits yielded the following results which fall in the HED meteorite field. All samples were cleaned in a 10% HCl solution for 1 minute, followed by ultrasonication.
δ17O = 1.57,δ18O = 3.57, Δ17O = -0.29 |
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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 07003 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample MIL 07003 | ||||
Thin Section Photo(s) : | ||||
References for Sample MIL07003 | |
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. | |
Greenwood, R. C., Barrat, J. A., Yamaguchi, A., Franchi, I. A., Scott, E. R., Bottke, W. F., Gibson, J. M., 2014, The oxygen isotope composition of diogenites: Evidence for early global melting on a single, compositionally diverse, HED parent body. Earth and Planetary Science Letters, 390, 165-174. | |
Barrat, J. A., Yamaguchi, A., Zanda, B., Bollinger, C., Bohn, M., 2010, Relative chronology of crust formation on asteroid Vesta: Insights from the geochemistry of diogenites. Geochimica et Cosmochimica Acta, 74 Issue 21, 1-Nov-10, 6218-6231, ISSN 0016-7037, http://dx.doi.org/10.1016/j.gca.2010.07.028. |