Sample Petrographic Description
Sample Number | LAP 10018 |
Newsletter | 36,2 |
Location | LaPaz Ice Field |
Field Number | 22976 |
Dimensions (cm) | 6.5 x 5.0 x 4.5 |
Weight (g) | 254.79 |
Original Classification | Howardite |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 29-45;Ferrosilite (mol%): 13-53 | |
Weathering | |
A | |
Fracturing | |
A/B | |
Macroscopic Description - Kathleen McBride | |
Shiny patches of brown/black fusion crust covers 60% of the exterior with some oxidation haloes and vugs. The interior is a gray matrix with no metal. Many angular multi-colored clasts of various sizes are visible. | |
Thin Section Description (,2) - Cari Corrigan, Linda Welzenbach | |
The section shows a groundmass of comminuted pyroxene and plagioclase (up to 0.5 mm) with a few fine- to coarse-grained basaltic clasts ranging up to 5 mm and one large diogenitic clast approaching 1 cm. Olivines are Fa29-45. Most of the pyroxene is orthopyroxene with compositions ranging from Fs22-53Wo2-11, a single augite of Fs13Wo39. Fe/Mn ratio is 21-36. The meteorite is a howardite. |
Antarctic Meteorite Images for Sample LAP 10018 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample LAP 10018 | ||||
Thin Section Photo(s) : | ||||
References for Sample LAP10018 | |
Tian, Z., Chen, H., Fegley Jr, B., Lodders, K., Barrat, J. A., Day, J. M., & Wang, K., 2019, Potassium isotopic compositions of howardite-eucrite-diogenite meteorites. Geochimica et Cosmochimica Acta, 266, 611-632, https://doi.org/10.1016/j.gca.2019.08.012. |