Sample Petrographic Description
Sample Number | LAP 03721 |
Newsletter | 29,2 |
Location | LaPaz Ice Field |
Field Number | 16503 |
Dimensions (cm) | 4.5 x 3.5 x 3.0 |
Weight (g) | 87.50 |
Original Classification | Ureilite |
Pairing | LAP 03721; LAP 031109; LAP 03722; |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 9-25 | |
Weathering | |
B | |
Fracturing | |
B/C | |
Macroscopic Description - Kathleen McBride, Cecilia Satterwhite | |
The exteriors have dark brown fusion crust exhibiting polygonal fractures and a few iridescent halos. Areas lacking fusion crust reveal a weathered brown interior. The interiors are hard but friable and revealed a dark gray matrix. Shiny grains with no apparent cleavage planes and translucent minerals with a slight yellow tint and opaque white to light gray grains are visible. | |
Thin Section Description (,2) - Valerie Reynolds, Tim McCoy | |
These sections are similar and almost certainly paired with LAP 03587, which was described as follows: The section consists of an aggregate of large olivine and pyroxene grains up to 2 mm across. Individual olivine grains are rimmed by carbon-rich material containing traces of metal. Shock effects in olivine are minor; pyroxenes exhibit mosaicism. Olivine has cores of Fa25, and rims of Fa10. Pigeonite is Fs14-20,Wo8-10. The meteorite is a ureilite. |
References for Sample LAP03721 | |
Budde, G., Burkhardt, C., and Kleine,T., 2020, Molybdenum isotopic evidence for the late accretion of outer Solar System material to Earth. Nature Astronomy, 3, 736–741. | |
Budde, G., Kruijer, T. S, Fischer-Godde, M., Irving, A. J., Kleine, T., 2015, Planetesimal differentiation revealed by the Hf-W systematics of ureilites. Earth and Planetary Science Letters, 430, 15-Nov-15, 316-325, ISSN 0012-821X, http://dx.doi.org/10.1016/j.epsl.2015.08.034. |