Sample Petrographic Description
Sample Number | RKP 80258 |
Newsletter | 5,1 |
Location | Reckling Peak |
Field Number | 1071 |
Dimensions (cm) | 1.5 x 1.5 x 1.0 |
Weight (g) | 4.28 |
Original Classification | Mesosiderite |
Pairing | RKP 79015; RKP 80229; RKP 80246; RKP 80258; RKP 80263; |
Mineral Composition (%Fa & %Fs) | |
Ferrosilite (mol%): 17-21 | |
Weathering | |
B/C | |
Fracturing | |
B | |
Macroscopic Description - Roberta Score | |
Fusion crust covers one surface of this meteorite. Visible on it are two large clasts, probably pyroxene, measuring 1.0 x 0.5 cm and 0.5 x 0.4 cm in dimension. both show cleavage faces. The specimen is highly weathered, although metal was detected in chipping. Sample is paired with RKPA 80229, RKPA 80246, and RKPA 80263. | |
Thin Section Description - Brian Mason | |
The section shows angular clasts of orthopyroxene up to 2 mm across in a nickel-iron matrix, closely resembling RKPA 79015, RKPA 80229, and RKPA 80246. A thick rind of red-brown limonite rims part of the section. Microprobe analyses show some variability in pyroxene composition: Wo2.3-2.9, En77-80, Fs17-21, in contrast to RKPA 79015, RKPA 80229, and RKPA 80246, in which the pyroxene has essentially uniform composition of Wo2En74Fs24. Rare grains of calcium-rich plagioclase of somewhat variable composition (An86 An94) were noted. The unique nature of these specimens and their otherwise close similarity indicates that they are probably pieces of a single meteorite, a metal-rich mesosiderite. |
Antarctic Meteorite Images for Sample RKP 80258 | ||||
Lab Photo(s) : | ||||
Antarctic Meteorite Images for Sample RKP 80258 | ||||
Thin Section Photo(s) : | ||||
References for Sample RKP80258 | |
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. | |
Hewins, R. H., 1988, Petrology and Pairing of Mesosiderites from Victoria Land, Antarctica. Meteoritics, 23, 123-129. | |
Scott, E. R. D., 1984, Pairing of meteorites found in Victoria Land, Antarctica. Memoirs of National Institute of Polar Research., Special issue 35, 102-125, http://ci.nii.ac.jp/naid/110000009967/en/. | |
Hewins, R. H., 1984, The case for a melt matrix in plagioclase-POIK mesosiderites. Journal of Geophysical Research: Solid Earth, 89, C289-C297, http://dx.doi.org/10.1029/JB089iS01p0C289. | |
Clarke Jr., R. S., Mason, B., 1982, Characterization of the 1980-81 Victoria Land meteorite collections. Memoirs of National Institute of Polar Research., Special Issue 25, 17-33, http://ci.nii.ac.jp/naid/110000009667/en/. | |
Clarke Jr., R. S., Mason, B., 1982, A new metal-rich mesosiderite from Antarctica, RKPA79015. Memoirs of National Institute of Polar Research., Special Issue 25, 78-85, http://ci.nii.ac.jp/naid/110000009670/en/. |