Sample Petrographic Description
Sample Number | LAP 031156 |
Newsletter | 29,1 |
Location | LaPaz Ice Field |
Field Number | 16357 |
Dimensions (cm) | 2.5 x 2.5 x 1.5 |
Weight (g) | 14.65 |
Original Classification | R Chondrite |
Updated Classification | R4 Chondrite |
Pairing | LAP 031135; LAP 031156; |
Mineral Composition (%Fa & %Fs) | |
Fayalite (mol%): 38;Ferrosilite (mol%): 31 | |
Weathering | |
B | |
Fracturing | |
B | |
Macroscopic Description - Kathleen McBride | |
Exteriors are covered with fractured black fusion crust. The interiors consist of fine grained gray matrix with dark gray inclusions. | |
Thin Section Description (,2) - Tim McCoy, Linda Welzenbach | |
The sections are so similar that single description suffices. The sections consist of ~50% of well-defined, small (up to 1 mm) chondrules set in a slightly recrystallized matrix of silicates and sulfides (both troilite and pentlandite). Olivine is homogeneous (Fa39-40) and pyroxene exhibits a small range (Fs21-31). The meteorites are R chondrites, probably of petrologic type 4. | |
Reclassification Notes (AMN 31,1) | |
Reclassified as R4 Chondrite in AMN 31,1. |
Antarctic Meteorite Images for Sample LAP 031156 | ||||
Lab Photo(s) : | ||||
References for Sample LAP031156 | |
Isa, J., Rubin, A. E., Wasson, J. T., 2014, R-chondrite bulk-chemical compositions and diverse oxides: Implications for parent-body processes. Geochimica et Cosmochimica Acta, 124, 1-Jan-14, 131-151, ISSN 0016-7037, http://dx.doi.org/10.1016/j.gca.2013.09.018. | |
Bischoff, A., Vogel, N., Roszjar, J., 2011, The Rumuruti chondrite group. Chemie der Erde - Geochemistry, 71 Issue 2, May-11, 101-133, ISSN 0009-2819, http://dx.doi.org/10.1016/j.chemer.2011.02.005. | |
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. |