Sample Petrographic Description
Sample Number | GRA 98030 |
Newsletter | 23,1 |
Location | Graves Nunataks |
Field Number | 11908 |
Dimensions (cm) | 3.5 x 2.5 x 2.0 |
Weight (g) | 32.62 |
Original Classification | Howardite |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 12;Ferrosilite (mol%): 21-52 | |
Weathering | |
A/B | |
Fracturing | |
A/B | |
Macroscopic Description - Kathleen McBride | |
Dark brown/black fusion crust covers approximately 40% of the surface of the meteorite. The interior reveals a tan weathering rind. The matrix is gray with black, white, and yellowish colored inclusions, angular to sub-angular in shape. The rock is soft and powdery. | |
Thin Section Description (,2) - Tim McCoy | |
The section shows a groundmass of comminuted pyroxene and plagioclase (up to 0.5 mm) with fine- to coarse-grained basaltic clasts ranging up to 5 mm. Most of the pyroxene is orthopyroxene with compositions ranging from Fs21-52 Wo1-4 (most Fs20-30), a single augite of Fs19Wo41 and an olivine of Fa12. The meteorite is a howardite. |
Antarctic Meteorite Images for Sample GRA 98030 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample GRA 98030 | ||||
Thin Section Photo(s) : | ||||
References for Sample GRA98030 | |
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. | |
Shearer, C. K., Burger, P., Papike, J. J., 2010, Petrogenetic relationships between diogenites and olivine diogenites: Implications for magmatism on the HED parent body. Geochimica et Cosmochimica Acta, 74 Issue 16, 15-Aug-10, 4865-4880, ISSN 0016-7037, http://dx.doi.org/10.1016/j.gca.2010.05.015. |