Sample Petrographic Description
Sample Number | GRA 98005 |
Newsletter | 22,2 |
Location | Graves Nunataks |
Field Number | 11992 |
Dimensions (cm) | 8.0 x 5.5 x 2.5 |
Weight (g) | 202.85 |
Original Classification | C2 Chondrite |
Updated Classification | CM2 Chondrite |
Pairing | GRA 98005; GRA 98074; |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 0-4;Ferrosilite (mol%): 1-2 | |
Weathering | |
Ce | |
Fracturing | |
B/C | |
Macroscopic Description - Kathleen McBride | |
The exterior of this carbonaceous chondrite is dull and black with white evaporites along the edges. The top face has a large yellowish brown inclusion. The meteorite appears to have no fusion crust. The interior is brown, very weathered and crumbles easily. Evaporite deposits are present on the interior surface. | |
Thin Section Description (,6) - Tim McCoy | |
The section consists of a few small chondrules (up to 0.5 mm), mineral grains and CAIs set in a black matrix; rare metal and sulfide grains are present. Olivine compositions are Fa0-4, orthopyroxene is Fs1-2. The matrix consists dominantly of an Fe-rich serpentine. The meteorite is a C2 chondrite. | |
Reclassification Notes (AMN 33,1) | |
Many carbonaceous chondrites were initially classified as C2 in early newsletters. These are mostly CM2, based on matrix properties, chondrules abundance and sizes, and therefore all these samples have been reclassified more specifically here as CM2. |
Antarctic Meteorite Images for Sample GRA 98005 | ||||
Lab Photo(s) : | ||||
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Antarctic Meteorite Images for Sample GRA 98005 | ||||
Thin Section Photo(s) : | ||||
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References for Sample GRA98005 | |
Alexander, C.M.O'D., Wynn, J.G., and Bowden, R., 2022, Sulfur abundances and isotopic compositions in bulk carbonaceous chondrites and insoluble organic material: Clues to elemental and isotopic fractions of volatile chalcophiles, Meteoritics & Planetary Science, 57, 334-351, doi:10.1111/maps.13746. | |
Alexander, C.M.O'D., Wynn, J.G., and Bowden, R., 2022, Sulfur abundances and isotopic compositions in bulk carbonaceous chondrites and insoluble organic material: Clues to elemental and isotopic fractions of volatile chalcophiles, Meteoritics & Planetary Science, 57, 334-351, doi:10.1111/maps.13746. | |
Krietsch, D., Busemann, H., Riebe, M.E.I., King, A.J., Alexander, C.M.O’D., Maden, C., 2021, Noble gases in CM carbonaceous chondrites: Effect of parent body aqueous and thermal alteration and cosmic ray exposure ages. Geochimica et Cosmochimica Acta, 310, 240–280, https://doi.org/10.1016/j.gca.2021.05.050. | |
Alexander, C. M. O'D., Bowden, R., Fogel, M. L., Howard, K. T., 2015, Carbonate abundances and isotopic compositions in chondrites. Meteoritics & Planetary Science, 50, 810-833, http://dx.doi.org/10.1111/maps.12410. | |
Alexander, C.O'D. M. O, Bowden,. R., Fogel, M. L., Howard, K. T., Herd, C. D. K., Nittler, L. R., 2012, The provenances of asteroids, and their contributions to the volatile inventories of the terrestrial planets. Science, 337(6095), 2012, 721-723. | |
Rochette, P., Kohout, T., Pesonen, L., Quirico, E., Sagnotti, L., Skripnik, A., Gattacceca, J., Bonal, L., Bourot-Denise, M., Chevrier, V., Clerc, J. P., Consolmagno, G., Folco, L., Gounelle, M., 2008, Magnetic classification of stony meteorites: 2. Non-ordinary chondrites. Meteoritics & Planetary Science, 43, 959-980, http://dx.doi.org/10.1111/j.1945-5100.2008.tb01092.x. |