Sample Petrographic Description
Sample Number | EET 87735 |
Newsletter | 12,3 |
Location | Elephant Moraine |
Field Number | 4322 |
Dimensions (cm) | 2.0 x 1.5 x 4.0 |
Weight (g) | 4.16 |
Original Classification | L3 Chondrite |
Updated Classification | L3.05 Chondrite |
Pairing | EET 87735; EET 90080; EET 90519; EET 90916; |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 1-25;Ferrosilite (mol%): 2-22 | |
Weathering | |
B | |
Fracturing | |
B | |
Macroscopic Description - Carol Schwarz | |
Fractured black fusion crust covers 90% of this unequilibrated chondrite. Numerous inclusions < 1mm in size are visible in the dark matrix. | |
Thin Section Description (,2) - Brian Mason | |
The section shows abundant chondrules and chondrule fragments, up to 1.8 mm across, in a black matrix containing some troilite and a little nickel-iron, which are concentrated as rims to the chondrules. A variety of chondrule types is present, including granular and porphyritic olivine and olivine-pyroxene, barred olivine, and fine-grained radiating pyroxene. Microprobe analyses show olivine and pyroxene of variable composition: olivine, Fa1-25, mean Fa12 (CV FeO is 60); pyroxene, Fs2-22. The small amount of nickel-iron suggests L group, and the variability of olivine and pyroxene compositions type 3; hence the meteorite is classified as an L3 chondrite (estimated L3.4). | |
Reclassification Notes (AMN 44,2) | |
Reclassified as an L3.05 Chondrite based on Cr contents of Type II chondrule olivine. Pairing groups adjusted based on olivine composition and recovery location. Righter, K., Schutt, J., Lunning, N., Harvey, R., & Karner, J. (2021a) Identification and pairing reassessment of unequilibrated ordinary chondrites from four Antarctic dense collection areas. Meteoritics & Planetary Science 56, 1556-1578. |
Antarctic Meteorite Images for Sample EET 87735 | ||||
Thin Section Photo(s) : | ||||
References for Sample EET87735 | |
Eschrig, J., Bonal, L., Mahlke, M., Carry,B., Beck, P., Gattacceca, J., 2022, Investigating S-type asteroid surfaces through reflectance spectra of ordinary chondrites, Icarus, 381. | |
Righter, K., Schutt, J., Lunning, N., Harvey, R, and Karner, J., 2021, Identification and pairing reassessment of unequilibrated ordinary chondrites from four Antarctic dense collection areas. Meteoritics & Planetary Science, 56, 1556-1573, doi: 10.1111/maps.13707. | |
Eschrig, J., Bonal, L., Beck, P., Prestgard, T.J., 2021, Spectral reflectance analysis of type 3 carbonaceous chondrites and search for their asteroidal parent bodies. Icarus, 354, 114034, https://doi.org/10.1016/j.icarus.2020.114034. | |
Telus, M., Huss, G. R., Ogliore, R. C., Nagashima, K., Howard, D. L., Newville, M. G., Tomkins, A. G., 2016, Mobility of iron and nickel at low temperatures: Implications for 60 Fe–60 Ni systematics of chondrules from unequilibrated ordinary chondrites. Geochimica et Cosmochimica Acta, 178, 87-105. | |
Bonal, L., Quirico, E., Flandinet, L., Montagnac, G., 2016, Thermal history of type 3 chondrites from the Antarctic meteorite collection determined by Raman spectroscopy of their polyaromatic carbonaceous matter. Geochimica et Cosmochimica Acta, 189, 312-337. | |
Krot, A. N., Zolensky, M. E., Wasson, J. T., Scott, E. R. D., Keil, K., Ohsumi, K., 1997, Carbide-magnetite assemblages in type-3 ordinary chondrites. Geochimica et Cosmochimica Acta, 61 Issue 1, Jan-97, 219-237, ISSN 0016-7037, http://dx.doi.org/10.1016/S0016-7037(96)00336-5. |