Lunar Meteorite: Elephant Moraine 87521 and 96008

Listed in The Meteoritical Bulletin, No. 76

Original classification from
Antarctic Meteorite Newsletter, Vol. 11, No. 2, 1988 (p. 21)

Elephant Moraine 87521 (EET 87521)

Dimensions (cm): 3.7 x 2.5 x 2
Found: 1987 December 20
Mass: 30.7 g (1 piece)

Brecciated Eucrite

Physical Description: Carol Schwarz. About 30% of this smooth rounded specimen is covered with black to brown shiny fusion crust. The interior of this breccia is dark and fine-grained with white and yellowish inclusions. It is coherent and has several large 2-3 mm white inclusions located near the exterior of the specimen.

Petrographic Description: Brian Mason. The section shows a microbreccia of pale brown pyroxene and colorless plagioclase clasts, up to 1.2 mm across, in a comminuted groundmass of these minerals. Pyroxene compositions show a wide range: Wo_15-39, Fs_41-61, En_12-41, but cluster around Wo₂₀Fs₄₅ and Wo₃₇Fs₄₈ (one grain is Wo₂₂Fs₆₁). One grain of Fe-rich olivine, Fa₉₁, was analyzed. Plagioclase composition is An_68-89. An SiO₂ polymorph, probably tridymite, is present in accessory amounts. The meteorite is a brecciated eucrite, but the iron-rich nature of the pyroxenes and the presence of fayalitic olivine distinguishes it from most eucrites.

Reclassification from
Antarctic Meteorite Newsletter, Vol. 13, No. 2, 1990 (PDF p. 17)

Lunar Basaltic Breccia

Macroscopic Description: Carol Schwarz and Marilyn Lindstrom. About 30% of this smooth rounded specimen is covered with black to brown shiny fusion crust. The interior of this coherent breccia is dark and fine-grained and contains numerous small white and yellow inclusions. Two 2-3 mm clasts are visible on the surface: One is a white clast consisting of plagioclase with 10-15% yellow and black mafic minerals; the other is a buff-colored clast made up of plagioclase and 35-50% yellow and black mafic minerals.

Thin Section (EET87521,8 & ,9) and Bulk Composition (EET87521,6) Description: Jeremy Delaney and Paul Warren. EET87521 was originally classified as a eucrite. However, more detailed investigations indicate that it is a very-low-titanium (VLT) basaltic breccia of lunar derivation. The modal mineralogy is 5-10% olivine, 45-50% pyroxene, 35-40% plagioclase and 1-2% ilmenite, chromite, ulvospinel/magnetite, sulfide, silica minerals, and FeNi-metal. The matrix of the meteorite also contains several percent of glass similar in composition to the bulk meteorite. The olivine ranges in composition from Fo₆₅ to Fo₅, a range typical of VLT mare basalts, and shows a strong bimodality with clusters centered at Fo_57-65 and Fo_5-15. Intermediate olivine compositions are uncommon. Molar Fe/Mn ratios of the olivine are 90-100. The pyroxene is pigeonite/subcalcic augite/augite with a composition range of En₆₅Wo_5-10 to En₂₀Wo_15-40. Most pyroxene is iron-rich and comparable to eucritic pyroxene, but is generally more calcic than eucritic pyroxene. The pyroxene does not show the bimodal distribution of the olivine. Pyroxene Fe/Mn ratios are 50-75. These ratios are typical of mare basalts, and much higher than those of basaltic achondrites (30-40). The feldspar is mostly An_93-97 with a few more sodic grains present. Several clasts within the thin sections have survived with textures little altered by brecciation. These clasts tend to be relatively coarse-grained, by mare basalt standards. Thin section [,9] contains a small (1 mm) clast of what is probably a highlands impact melt breccia. This extremely fine-grained clast contains at least 70% plagioclase. It also contains the only observed grains of FeNi-metal, with compositions (average 94.1% Fe, 4.53% Ni, 0.37% Co) typical of metals derived as “contamination” from metal-rich meteorites. The bulk composition of EET87521 has been studied by INAA, using two adjacent chips, 278-290 mg in mass. The TiO₂ concentration is 0.8-1.1%, and results for ratios such as Fe/Mn, Ga/Al, Na/Ca, and Co/Cr indicate that this sample is lunar, and certainly not a eucrite. In general, the bulk composition shows a striking resemblance to VLT mare basalts from Luna 24. Perhaps the most significant difference is that EET87521 has higher concentrations of incompatible elements, especially light REE. This difference might be caused by the highlands component associated with the FeNi-bearing clast. However, the bulk-rock Ni content (29-43 µg/g) indicates that the total proportion of non-VLT “contaminant” is probably small.

References: J. Delaney (1989) Nature 342, 889-890. P. Warren and G. Kallemeyn (1989) Geochim. Cosmochim. Acta 53, 3323-3330.

Oxygen Isotopic Composition: Robert Clayton. The oxygen isotopic composition is δ¹⁸O = +5.39, δ¹⁷O = +2.79. These analyses are comparable to those of previously analyzed lunar meteorites and Apollo lunar samples and distinct from those of eucrites.

Listed in The Meteoritical Bulletin, No. 82

from Antarctic Meteorite Newsletter, Vol. 21, No. 1, 1998

Elephant Moraine 96008

Transantarctic Mountains, Antarctica

Dimensions (cm): 4.5×3.5×1.5
Found: 1996 December 14
Mass: 52.97 g (1 piece)

Lunar Basaltic Breccia

Macroscopic Description: Kathleen McBride. 50% of this meteorite is covered by a black glassy fusion crust. Areas that lack fusion crust appear virtually unweathered. The fusion crust is very thinly distributed over the surface of the rock. The matrix is fine grained, medium gray with numerous inclusions. These inclusions are white, light gray and tan and are angular and subangular in shape. Metal and rust are not visible. This is a brecciated basalt, possibly lunar in origin.

Thin Section (,4) Description: Brian Mason. The section shows a microbreccia of pyroxene and plagioclase clasts, up to 1.2 mm across; traces of nickel-iron and sulfide are present, as small scattered grains. Microprobe analyses show that most of the pyroxene ranges from Wo₁₁Fs₃₁ to Wo₄₀ Fs₁₈, with a few more iron-rich grains; plagioclase composition is An_93-96. A few olivine grains of variable composition, Fa_41-64, were analyzed. Fe/Mn in pyroxene is about 70. The meteorite is a lunar basaltic breccia.

Randy Says…

The paired stones were found 9 years apart.

There are some compositional reasons to suspect that EET 87/96 is launch-paired with DEW 12007, QUE 94281, Yamato 793274/981031, NWA 4884, the NWA 7611 clan. See discussion at the NWA 7611 clan.

More Information

Meteoritical Bulletin Database

EET 87521 | 96008

Map

ANSMET Location Map

References

Arai T., Takeda H., and Warren P. H. (1996) Four lunar meteorites: Crystallization trends of pyroxenes and spinels. Meteoritics & Planetary Science 31, 877-892.

Arai T., Shimoda H., Kita N., and Morishita Y. (2005) Petrogenesis of basaltic clasts with extreme compositional variations in a brecciated lunar meteorite EET 87521. Antarctic Meteorites XXIX, 1-2.

Arai T., Shimoda H., Kita N., Morishita Y., and Kojima H. (2005) Source magma compositions for basalt clasts of lunar meteorite EET 87521 in connection to KREEP. 68th Annual Meeting of the Meteoritical Society, abstract no. 5196.

Basilevsky A. T., Neukum G., and Nyquist L. (2010) Lunar meteorites: What they tell us about the spatial and temporal distribution of mare basalts. 41st Lunar and Planetary Science Conference, abstract no. 1214.

Boesenberg J. S. and Delaney J. S. (2006) Elephant Moraine 87521: Two pyroxenes, two chromites, and two ilmenites, but only one fractionation series. In Lunar and Planetary Science XXXVII, abstract no. 1680.

Delaney J. S. (1989) Lunar basalt breccia identified among Antarctic meteorites. Nature 342, 889-890.

Distel A. G., Davidson J., Wadhwa M., Hervig R. L., Sutton S. R., and Lanzirotti A. (2024) Correlated H₂O–δD systematics and iron and chromium valences of nominally anhydrous minerals in the lunar basaltic breccia meteorite Elephant Moraine (EET) 87521. 55th Lunar and Planetary Science Conference, abstract no. 1721.

Dreibus G., Spettel B., Wlotzka F., Jochum K. P., Schultz L., Weber H. W., and Wänke H. (1996) Chemistry, petrology, and noble gases of basaltic lunar meteorite QUE 94281. Meteoritics & Planetary Science 31, A38-A39.

Eugster O., Thalmann Ch., Albrecht A., Herzog G. F., Delaney J. S., Klein J., and Middleton R. (1996) Exposure history of glass and breccia phases of lunar meteorite EET87521. Meteoritics & Planetary Science 31, 299-304.

Eugster O., Polnau E., Salerno E., and Terribilini D. (2000) Lunar surface exposure models for meteorites Elephant Moraine 96008 and Dar al Gani 262 from the Moon. Meteoritics & Planetary Science 35, 1177-1181.

Fernandes V. A. and Burgess R. (2006) Ar-Ar studies of two lunar mare rocks: LAP02205 and EET96008. Lunar and Planetary Science XXXVII, abstract no. 1145.

Fernandes V. A., Burgess R., and Morris A. (2009) ⁴⁰Ar-³⁹Ar age determinations of lunar basalt meteorites Asuka 881757, Yamato 793169, Miller Range 05035, LaPaz Icefield 02205, Northwest Africa 479, and basaltic breccia Elephant Moraine 96008. Meteoritics & Planetary Science 44, 805-821.

Fernandes V. A. S. M., Fritz J. P., Wünnemann K., and Hornemann U. (2010) K-Ar ages and shock effects in lunar meteorites. EPSC Abstracts, Vol. 5, EPSC2010-237.

Fritz J. (2012) Impact ejection of lunar meteorites and the age of Giordano Bruno. Icarus 221, 1183-1186.

Hayden T. S., Barrett T. J., Zhao X., Degli-Alessandrini G., Anand M., Franchi I. A. (2021) Chlorine and hydrogen in brecciated lunar meteorites: Implications for lunar volatile history. 52nd Lunar and Planetary Science Conference, abstract no. 1550.

Isaacson P. J., Liu Y., Patchen A., Pieters C. M., and Taylor L. A. (2009) Integrated analyses of lunar meteorites: Expanded data for lunar ground truth. 40th Lunar and Planetary Science Conference, abstract no. 2119.

Isaacson P. J., Liu Y., Patchen A. D., Pieters C. M., and Taylor L. A. (2010) Spectroscopy of lunar meteorites as constraints for ground truth: Expanded sample collection diversity. 41st Lunar and Planetary Science Conference, abstract no. 1927.

Jull A. J. T. and Donahue, D. J. (1992) ¹⁴C Terrestrial ages of two lunar meteorites, ALHA 81005 and EET 87521. Lunar and Planetary Science XXIII, 637-638.

Karouji Y., Oura Y., and Ebihara M. (2002) Chemical composition of lunar meteorites including Yamato 981031. Antarctic Meteorites XXVII, 52–54.

Korotev R. L. (2005) Lunar geochemistry as told by lunar meteorites. Chemie der Erde 65, 297-346.

Korotev R. L. and Zeigler R. A. (2014) Chapter 6. ANSMET Meteorites from the Moon, Thirty-five Seasons of U.S. Antarctic Meteorites (1976–2010): A Pictorial Guide to the Collection (editors K. Righter, R. P. Harvey, C. M. Corrigan, and T. J. McCoy), 101–130, Special Publications 68, American Geophysical Union, Washington, D. C., 296 pages, ISBN: 978-1-118-79832-4.

Korotev R. L., Jolliff B. L., Zeigler R. A., and Haskin L. A. (2003) Compositional evidence for launch pairing of the YQ and Elephant Moraine lunar meteorites. Lunar and Planetary Science 34, abstract no. 1357.

Korotev R. L., Jolliff B. L., Zeigler R. A., and Haskin L. A. (2003) Compositional constraints on the launch pairing of three brecciated lunar meteorites of basaltic composition. Antarctic Meteorite Research 16, 152-175.

Korotev R. L., Irving A. J., and Bunch T. E. (2008) Keeping up with the lunar meteorites – 2008. Lunar and Planetary Science XXXIX, abstract no. 1209, 39th Lunar and Planetary Science Conference.

Korotev R. L, Zeigler R. A., Jolliff B. L., Irving A. J., and Bunch T. E. (2009) Compositional and lithological diversity among brecciated lunar meteorites of intermediate iron composition. Meteoritics & Planetary Science 44, 1287-1322.

Lindstrom M. M., Mittlefehldt D. W., and Martinez R. R. (1999) Basaltic lunar meteorite EET96008 and evidence for pairing with EET87521. Lunar and Planetary Science XXX, abstract no. 1921.

Miao B., Chen H., Xia Z., Xie L., and Yao J. (2013) The type, occurrence and origin of symplectites in lunar meteorites. 76th Annual Meeting of the Meteoritical Society, abstract no. 5234.

Mikouchi T. (1999) Mineralogy and petrology of a new lunar meteorite EET96008: Lunar basaltic breccia similar to Y-793274, QUE94281 and EET87521. Lunar and Planetary Science XXX, abstract no. 1558.

Morris A., Fernandes V., and Burgess R. (2008) Ar-Ar ages for lunar basalt meteorites: A 881757, Y 793169, MIL 05035, LAP 02205, NWA479 and EET 96008. Goldschmidt Conference Abstracts 2008, Geochimica et Cosmochimica Acta 72, 12S, A652.

Nishiizumi K. (2003) Exposure histories of lunar meteorites. Evolution of Solar System Materials: A New Perspective from Antarctic Meteorites,

Nishiizumi K., Masarik J., Caffee M. W., and Jull A. J. T. (1999) Exposure histories of pair lunar meteorites EET 96008 and EET 87521. Lunar and Planetary Science XXX, abstract no. 1980.

Snyder G. A., Taylor L. A., and Patchen A. (1999) Lunar meteorite EET 96008, Part I. Petrology & mineral chemistry: Evidence of large-scale, late-stage fractionation. Lunar and Planetary Science XXX, abstract no. 1499.

Snyder G. A., Neal C. R., Ruzicka A. M., and Taylor L. A. (1999) Lunar meteorite EET 96008, Part II. Whole-rock trace-element and PGE chemistry, and pairing with EET 87521. Lunar and Planetary Science 30, abstract no.1705.

Takeda H., Mori H., Saito J., and Miyamoto M. (1992) Mineralogical studies of lunar mare meteorites EET87521 and Y793274. Proceedings of Lunar and Planetary Science, Volume 22, 355-364.

Terada K. and Sano Y. (2005) In-situ U-Pb dating of phosphates in lunar basaltic breccia Elephant Moraine 87521. 68th Annual Meeting of the Meteoritical Society, abstract no. 5062.

Terada K. and Sano Y. (2005) In-situ U-Pb dating of phosphates in lunar basaltic breccia Elephant Moraine 87521 and EET96008, Antarctic Meteorites XXIX, 86-87.

Terada K., Saiki T., Oka Y., Hayasaka Y., and Sano Y. (2005) Ion microprobe U-Pb dating of phosphates in lunar basaltic breccia, Elephant Moraine 87521. Geophysical Research Letters 32(20), L20202. DOI 10.1029/2005GL023909

Terada K., Sasaki Y., and Sano Y. (2006) In-situ U-Pb dating of phosphates in lunar basaltic breccia Yamato 981031. Lunar and Planetary Science XXXVII, abstract no. 1665.

Vogt S., Herzog G. F., Eugster O., Michel Th., Nidermann S., Krähenbühl U., Middleton R., Dezfouly-Arjomandy B., and Klein J. (1993) Exposure history of the lunar meteorite, Elephant Moraine 87521. Geochimica et Cosmochimica Acta 57, 3793-3799.

Warren P. H. and Kallemeyn G. W. (1989) Elephant Moraine 87521: The first lunar meteorite composed of predominantly mare material. Geochimica et Cosmochimica Acta 53, 3323-3300.

Warren P. H. and Kallemeyn G. W. (1991) Geochemical investigations of five lunar meteorites: Implications for the composition, origin and evolution of the lunar crust. Proceedings of the NIPR Symposium on Antarctic Meteorites 4, 91-117.

Warren P. H. and Ulff-Møller F. (1999) Lunar meteorite EET96008: Paired with EET87521, but rich in diverse clasts. Lunar and Planetary Science XXXI, abstract no. 1450.

Wolf S. F., Wang M.S., and Lipschutz M. E. (2009) Labile trace elements in basaltic achondrites: Can they distinguish between meteorites from the Moon, Mars, and V-type asteroids? Meteoritics & Planetary Science 44, 891–903.

Yanai K. and Kojima H. (1991) Varieties of lunar meteorites recovered from Antarctica. Proceedings of the NIPR Symposium on Antarctic Meteorites 4, 70-90.