Eucrite : DaG 863
found 1999 on Dar al Gani plateau, Libya


eucrite polymict: Dar al Gani 863



Extract from Meteoritics And Planetary Science, Vol.36, N°9, A190

A Comparison of a New Polymict Eucrite DaG 863 to Other Eucrites Recovered from Dar al Gani, Libya. P.P. Sipiera, Schmitt Meteorite Research Group, Harper College, Palatine, IL 60067, USA, G.A. Jerman, Material Processing Laboratory, NASA Marshall Space Flight Center, Huntsville, Alabama 35812, Richard Pelisson and Roland Pelisson, SaharaMet, La Terrasse, France.

Results: A single blackened 361gram achondrite was found in Dar al Gani, Libya at Lat. 26 deg. 55.17' N and Long. 16 deg. 40.44' E. Petrographically, a cut and polished surface reveals an achondritic texture with a contact boundary defining two distinct lithologies. The first is a lighter colored gray brecciated basaltic texture that contrasts a second darker gray texture which features larger clasts. Metal is present throughout the meteorite but is most apparent along the boundary that separates the two lithologies. In probe section the two lithologies are easily distinguishable by the presence of the larger clasts consisting of cumulate xenoliths with triple point junctions. Mineralogically, DaG 863 is dominated by ortho-pyroxene (Fs61.4, Wo2.1), and as secondary phases clino-pyroxene (Fs30.6, Wo39.5) and plagioclase (An87.7). In addition, chromite and zircon were noted as accessory minerals.

Summary: In consideration of its mineralogy and petrology DaG 863 is best classified as a polymict eucrite and may be paired with one or more of the other Dar al Gani eucrites listed in Table 1. The obvious question is how many of these eucrites are actually from a single mass/fall, or do they truly each represent a separate fall? Since at least four of these eucrites are polymict breccias this suggests that the parent body certainly had a diverse lithology and that these individuals may represent random samplings of that object...


Science needs good documentation.

All the meteorites discovered during our expeditions have been documented in great detail, with photos of the principal mass, analysis results, and images of cuttings showing their internal structure. All this information is stored on CD-ROM.



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