Lunar Meteorite: Dhofar 925 clan

from The Meteoritical Bulletin, No. 88

Dhofar 925

Oman
Found: 2003 February 6
Mass: 49 g (1 piece)

Lunar meteorite (VLT basalt-bearing feldspathic impact melt breccia)

History: A grey stone weighing 49 g was found in the Dhofar region of Oman.

Mineralogy and classification (S. Demidova, M. Nazarov, Vernad., G. Kurat, NHMV): fusion crust is absent. The meteorite is an impact melt breccia; abundant mineral fragments and lithic clasts are set within a fine-grained impact melt matrix; the lithic clast population is dominated by impact melt breccias and granulitic rocks of anorthositic, troctolitic, noritic, and gabbronoritic compositions; the presence of VLT mare basalt clasts and rare KREEPy and granitic fragments is a characteristic feature of this meteorite; glass veins and fragments are common; feldspar, An_2-98Or_0-85; orthopyroxene, Wo_2-5En_49-90; clinopyroxene; Wo_5-47En_0.1-79, olivine, Fo_0.5-93 (Fe/Mn ~ 87 at); accessory minerals are ulvöspinel, Ti-rich chromite, pleonaste, ilmenite (0.4-7.4 wt % MgO), silica, troilite, and abundant FeNi metal (0.6-24 wt% Ni; 0.1-1.5 wt% Co); K-Ba feldspar, whitlockite, Cl-apatite, baddeleyite, zircon, Zr-armalcolite, monazite, tranquillityite, and zirconolite occur in granitic clasts. One fragment of tschermakitic amphibole was found. The stone is moderately weathered; calcite, gypsum, celestite, barite, smectite and Fe hydroxides are present. The meteorite was found close to Dho 489 but the stones are very different in composition. Dho 489 does not contain any mare basalt material.

Specimens: type specimens of 10.1 g, and 2 thin sections, Vernad.; main mass with anonymous finder.

from The Meteoritical Bulletin, No. 89

Dhofar 960

Oman
Found: 2003 November 16
Mass: 35.4 g (1 piece)

Lunar meteorite (feldspathic impact melt breccia)

History: A grey stone weighing 35.4 g was found in the Dhofar region of Oman.

Mineralogy and classification (S. Demidova, Vernad., F. Brandstätter, NHMV): Fusion crust is absent. The meteorite is an impact melt breccia with abundant mineral fragments and lithic clasts set within a fine-grained impact melt matrix. The lithic clasts are impact melt breccias and granulitic rocks of anorthositic, gabbro-noritic, troctolitic, and noritic compositions. A presence of VLT mare basalt clasts, KREEPy and rare granitic fragments is a characteristic feature of the meteorite. Glass veins and fragments are common. Mineral compositions are as follows; plagioclase, An_57-98Or_0-6; orthopyroxene, Wo₃–₅En_66-78; clinopyroxene; Wo_5-43En_0.4-73; olivine, Fo_4-90 (Fe/Mn ~= 92 at); accessory minerals are ulvöspinel, Cr-rich ulvöspinel, Ti-rich chromite, Al-rich chromite, pleonaste, ilmenite (0.7-7.4 wt.% MgO), silica, troilite, FeNi metal (5-21 wt.% Ni; 0.3-0.7 wt.% Co); K-Ba feldspar, pyroxferroite, whitlockite, apatite, baddeleyite, Zr-armalcolite and Zr-rich phases. The stone is moderately weathered; calcite, gypsum, celestite, smectite and Fe hydroxides are present. The meteorite was found close to Dho 925 and they are similar in texture, petrography and mineral chemistry. The stones may be paired.

Specimens: type specimens of 7.4 g and 2 thin sections deposited at Vernad. The main mass is held by an anonymous finder.

from The Meteoritical Bulletin, No. 89

Dhofar 961

Oman
Found: 2003 November 12
Mass: 21.6 g (1 piece)

Lunar meteorite (feldspathic impact melt breccia)

History: A grey stone weighing 21.6 g was found nearby to the Dho 925 and 960 lunar meteorites in the Dhofar region of Oman.

Mineralogy and classification (S. Demidova, Vernad, F. Brandstätter, NHMV): the meteorite is similar to Dho 925 and 960 in texture, mineralogy and mineral chemistry and the stones may be paired.

Specimens: type specimens of 4.8 g and a thin section on deposit at Vernad. The main mass is held by an anonymous finder.

Randy Says…

Compositionally, the Dhofar 925 clan is moderately mafic and moderately rich in KREEP elements and FeNi metal. Despite the textural similarity among Dhofar 925, Dhofar 960, and Dhofar 961, Dhofar 961 is more mafic and much richer in incompatible elements than the other two. Although compositionally distinct, Dhofar 1527 (10 km distant) may be another stone of the Dhofar 925 clan, as may Dhofar 2122 (3-4 km distant).

Compositionally and texturally, our samples of Dhofar 925 and Dhofar 960 are similar to Dhofar 1629, reportedly found 117 km to the southwest, and SaU 449, reportedly collected ~340 km to the northeast. Those distances are too far apart for the stones to be terrestrially paired, but they are candidate launch pairs.

The Dhofar 925 pair group and SaU 449 are compositionally indistinguishable from the Northwest Africa 8673. The textures are different, however.

More Information

Meteoritical Bulletin Database

Dhofar 925 | 960 | 961

Map

Schematic Map of  Find Locations of  Lunar Meteorite from Oman

References

Calzada-Diaz A., Joy K. H., Crawford I. A., and Nordheim T. A. (2015) Constraining the source regions of lunar meteorites using orbital geochemical data. Meteoritics & Planetary Science 50, 214-228.

Cohen B. A., Frasl B., Jolliff B. L., Korotev R. L., and Zeigler R. A. (2016) ⁴⁰Ar-³⁹Ar age of an impact-melt lithology in Dhofar 961. 47th Lunar and Planetary Science Conference, abstract no. 2007.

Demidova S. I., Nazarov M. A., Kurat G., Brandstätter F., and Ntaflos T. (2005) New lunar meteorites from Oman: Dhofar 925, 960 and 961. Lunar and Planetary Science 36, abstract no. 1607.

Demidova S. I., Nazarov M. A., Lorenz C. A., Kurat G., Brandstätter F., and Ntaflos Th. (2007) Chemical composition of lunar meteorites and the lunar crust. Petrology 15 (4), 386-407.

Demidova S. I., Nazarov M. A., Brandstätter F., and Ntaflos Th. (2014) Mineralogical evidence for the activity of lunar water. 45th Lunar and Planetary Science Conference, abstract no. 1087.

Jolliff B. L., Zeigler R. A., Korotev R. L., and Carpenter P. K. (2007) Lunar meteorite Dhofar 961, mafic impact-melt breccia: Petrographic components and possible provenance. 70th Annual Meeting of the Meteoritical Society, abstract no. 5311.

Jolliff B. L., Zeigler R. A., Korotev R. L., Carpenter P. K., Vicenzi E. P., and Davis J. M. (2008) Mafic impact-melt components in lunar meteorite Dhofar 961. Lunar and Planetary Science XXXIX, abstract no. 2519.

Jolliff B. L., Korotev R. L., Zeigler R. A., and Prettyman T. H. (2009) Connecting lunar meteorite Dhofar 961 to the South Pole-Aitken Basin through Lunar Prospector gamma-ray data. 40th Lunar and Planetary Science Conference, abstract no. 2555.

Joy K. H., Kring D. A., and Zolensky M. E. (2011) Petrography of lunar meteorites Dhofar 925 and 961. 74th Annual Meeting of the Meteoritical Society, abstract no. 5100.

Joy K. H., Nemchin A., Grange M., Lapen T. J., Peslier A. H., Ross D. K., Zolensky M. E., and Kring D. A. (2014) Petrography, geochronology and source terrain characteristics of lunar meteorites Dhofar 925, 961 and Sayh al Uhaymir 449. Geochimica et Cosmochimica Acta 144, 299-325.

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

Korotev R. L. (2006) New geochemical data for a some poorly characterized lunar meteorites. Lunar and Planetary Science XXVII, abstract no. 1404.

Korotev R. L. (2011) Lunar meteorites from Antarctica and Oman. 74th Annual Meeting of the Meteoritical Society, abstract no. 5073.

Korotev R. L. (2012) Lunar meteorites from Oman. Meteoritics & Planetary Science 47, 1365-1402.

Korotev R. L. (2017) Update (2012–2017) on lunar meteorites from Oman. Meteoritics & Planetary Science 52, 1251-1256.

All Korotev data on Omani lunar meteorites.

Korotev R. L. and Zeigler R. A. (2007) Keeping up with the lunar meteorites. Lunar and Planetary Science XXXVIII, abstract no. 1340.

Korotev R. L., Zeigler R. A., and Jolliff B. L. (2007) Do we have a meteorite from the South Pole-Aitken basin of the Moon? 70th Annual Meeting of the Meteoritical Society, abstract no. 5257.

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.

Korotev R. L., Zeigler R. A., and Jolliff B. L. (2010) New geochemical constraints on pairing of the Dhofar 961 clan of lunar meteorites. 41st Lunar and Planetary Science Conference, abstract no. 2126.

Rochette P., Gattacceca J., Ivanov A. V., Nazarov M. A., and Bezaeva N. S. (2010) Magnetic properties of lunar materials: Meteorites, Luna and Apollo returned samples. Earth and Planetary Science Letters 292, 383-391.

Zeigler R. A., Jolliff B. L., and Korotev R. L. (2010) Petrography and pairing relationships of lunar meteorites Sayh al Uhaymir 449 and Dhofar 925, 960, and 961. 41st Lunar and Planetary Science Conference, abstract no. 1985.

Zeigler R. A., Korotev R. L., and Jolliff B. L. (2010) The Dhofar 961 meteorite group: A view into the interior of South Pole Aitken basin? 33rd Symposium on Antarctic Meteorites.

Zeigler R. A., Jolliff B. L., and Korotev R. L. (2013) Lunar meteorites Sayh al Uhaymir 449 and Dhofar 925, 960, and 961: Windows into South Pole Aitken Basin?. 44th Lunar and Planetary Science Conference, abstract no. 2437.