Sample Petrographic Description
Sample Number | LAR 06870 |
Newsletter | 30,2 |
Location | Larkman Nunatak |
Field Number | 19944 |
Dimensions (cm) | 2.5 x 1.75 x 2.0 |
Weight (g) | 15.43 |
Original Classification | Eucrite (Brecciated) |
Mineral Composition (%Fa & %Fs) | |
Ferrosilite (mol%): 60 | |
Weathering | |
A/B | |
Fracturing | |
A/B | |
Macroscopic Description - Kathleen McBride | |
95% black fusion crust covers the exterior, which is dull on one surface and shiny on the other. The interior is a gray and white matrix with a powdery texture. | |
Thin Section Description - Tim McCoy, Linda Welzenbach | |
The meteorite is a breccia that has been metamorphosed and shocked. Basaltic clasts measuring from 0.5-4 mm vary widely in texture and grain size (0.1-1 mm), reflecting their variable cooling histories, and boundaries between clasts and matrix have been largely obscured by later metamorphism. Pyroxenes are exsolved and pervasive shock effects include mosaicism in pyroxene. Mineral compositions are nearly homogeneous with orthopyroxene (Fs60Wo2), augite (Fs30Wo39), and plagioclase (An78-86Or1). The Fe/Mn ratio of the pyroxene is ~30. The meteorite is a brecciated eucrite. |
Antarctic Meteorite Images for Sample LAR 06870 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample LAR 06870 | ||||
Thin Section Photo(s) : | ||||