NWA 2977 Lunar Meteorite - Rare Gabbro Moon Specimen

• Northwest Africa 2977

• Found in Algeria or Morocco November 2005

• Achondrite (Lunar Gabbro)

History: A single minimally weathered, fusion encrusted stone of 233 g was purchased from a Moroccan dealer in Tagounite, Morocco by M. Farmer in November 2005. Petrography and Geochemistry: (J. Wittke and T. Bunch, NAU; A. Irving, UWS) The specimen consists of a single yellow-green, relatively coarse-grained rock traversed by thin, black glass-rich, thin veins.  It is an olivine-rich, two-pyroxene cumulate gabbro composed of olivine 51%, Fa_31.7, FeO/MnO = 96; pigeonite 23%, Fs_26.6Wo_6.7; augite 9%, Fs_16.2Wo₂₉; plagioclase 14%, An₅₆ with minor amounts of Ba-K-feldspar, chromite, ilmenite, and merrillite. Larger pigeonite grains commonly enclose equant olivine grains, which contain abundant melt inclusions (0.025 to 0.125 mm).   Plagioclase is partially converted to maskelynite, and pyroxenes and olivine exhibit shock lamellae and undulatory extinction.  Noteworthy This specimen is identical in texture and mineral compositions to the gabbro clasts in NWA 773 and NWA 2700 and thus appears to be paired with those breccia specimens.  Classification: Achondrite (Lunar gabbro) with minor weathering.  Specimens: A 20.1 g specimen and one polished thin section are on deposit at NAU. A 0.5 g specimen is on deposit at WUSL. An anonymous owner holds the main mass.

Abstract submitted for presentation as poster at the LPSC in Houston in March, 2006.  PDF document. requires an Acrobat Reader (it is free):

LUNAR METEORITES NWA 2700, NWA 2727, AND NWA 2977: MARE BASALT/GABBRO BRECCIAS WITH AFFINITIES TO NWA 773.   T. E. Bunch, J. H. Wittke, R. L. Korotev, and A. J. Irving, Dept. of Geology, Northern Arizona University, Flagstaff, AZ 86011, Dept. of Earth & Planetary Sciences, Washington University, St. Louis, MO 63130, Dept. of Earth & Space Sciences, University of Washington, Seattle, WA  98195