Sample Petrographic Description
Sample Number | ALH 83015 |
Newsletter | 8,1 |
Location | Allan Hills |
Field Number | 2138 |
Dimensions (cm) | 1.5 x 1.5 x 1.0 |
Weight (g) | 3.13 |
Original Classification | Aubrite (?) |
Updated Classification | Aubrite |
Pairing | ALH 83009; ALH 83015; ALH 84007; ALH 84008; ALH 84009; ALH 84010; ALH 84011; ALH 84012; ALH 84013; ALH 84014; ALH 84015; ALH 84016; ALH 84017; ALH 84018; ALH 84019; ALH 84020; ALH 84021; ALH 84023; ALH 84024; |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 0;Ferrosilite (mol%): 0 | |
Weathering | |
A/B | |
Fracturing | |
A | |
Macroscopic Description - Roberta Score | |
This specimen is white in color and is identical in appearance to ALH83009. | |
Thin Section Description (,2) - Jeremy Delaney | |
ALH83015 is a pyroxenite breccia with clasts up to 1-5 mm. Matrix is very fine-grained with brown/green staining common. Pyroxene grains often contain submicron to 10 micron opaque (troilite?) inclusions on healed cracks. One heavily clouded pyroxene is also present. Areas of fine-grained breccia against coarse-grained breccia occur. Tiny olivine-troilite clasts are present, as are small matrix olivines. Large orthopyroxene clasts have mottled appearance and appear shocked. The pyroxene has no micron or larger scale exsolution and appears to be orthopyroxene. Brown staining caused by weathering of metal/troilite stains most grain boundaries and large troilite or metal clasts often have "rusty" halos. This specimen may be similar to the 83009 aubrite. Minor phases include daubreelite, alabandite, metal and Ti-bearing troilite. | |
Reclassification Notes (AMN 13,1) | |
Classification updated to Aubrite |
Antarctic Meteorite Images for Sample ALH 83015 | ||||
Thin Section Photo(s) : | ||||
References for Sample ALH83015 | |
Rubin, A. E., & Ma, C. , 2017, Meteoritic minerals and their origins. . Chemie der Erde-Geochemistry, 77, 325-385, http://dx.doi.org/10.1016/j.chemer.2017.01.005. | |
Rubin, A. E., 2015, Shock and annealing in aubrites: Implications for parent-body history. Meteoritics & Planetary Science, 50, 1217-1227, http://dx.doi.org/10.1111/maps.12464. | |
Keil, K., 2010, Enstatite achondrite meteorites (aubrites) and the histories of their asteroidal parent bodies. Chemie der Erde - Geochemistry, 70 Issue 4, 2010, 295-317, ISSN 0009-2819, http://dx.doi.org/10.1016/j.chemer.2010.02.002. | |
Benoit, P. H., Sears, D. W. G., Akridge, J. M. C., Bland, P. A., Berry, F. J., Pillinger, C. T., 2000, The non-trivial problem of meteorite pairing. Meteoritics & Planetary Science, 35, 393-417. | |
Marvin, U. B., MacPherson, G. J., 1989, Field and Laboratory Investigations of Meteorites from Victoria Land and the Thiel Mountains Region, Antarctica 1982-1983 and 1983-1984. Smithsonian Contributions to the Earth Sciences Number, 28, 146. |