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Lunar Meteorite: Dhofar 1436 & 1443 (paired stones)Oman |
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from The Meteoritical Bulletin, No. 93, Meteoritics & Planetary
Science 43, 571-632 (2007) Dhofar 1436Dhofar, Sultanate of OmanFind: 8 December 2004 Lunar meteorite (feldspathic impact melt breccia) History: This meteorite was discovered by an anonymous finder on a limestone plateau in the Dhofar region of Sultanate of Oman, far from other known lunar meteorites. Physical characteristics: A single brownish-green stone of 24.2 g total weight. Fusion crust is absent. Petrography: (Lorenz C. and Nazarov M., Vernad) The meteorite is an impact melt breccia, consisting of lithic and mineral clasts embedded in a partly devitrified glassy matrix with abundant bubbles. The lithic clasts are mainly impact melt breccias and rocks of anorthositic, gabbro-anorthositic, and gabbro-noritic compositions. Granular breccia clasts are also present. Lithic fragments range from 0.01 to 7 mm in size. Major minerals are pyroxene and feldspar, with minor olivine. Accessories are silica, chromite, ilmenite, Ca-phosphate, troilite and FeNi metal. Mineral composition and geochemistry: (Lorenz C., Kononkova N., Vernad, EMP): feldspar (An92.5-98.7Ab1.1-7.2); orthopyroxene (En68.2-84.1Wo0.2-5.0; Fe/Mn 62); clinopyroxene (En13.4-63.7Wo12.8-40.5; Fe/Mn 63); olivine (Fo42.6-72.7; Fe/Mn 96); spinel is Al-Ti-chromite. Average glassy matrix composition: SiO2 = 45.1, TiO2 = 0.26, Al2O3 = 30.8, FeO = 4.49, MgO = 3.94, CaO = 16.7, Na2O = 0.48, K2O = 0.04 [all wt%]. Oxygen Isotopes: (I. A. Franchi, OU) δ17O=3.286; δ18O=6.244 (both ‰) Classification: Lunar meteorite (feldspathic impact melt breccia): minor weathering. Specimens: A type specimen of 5.2 g and one thin section are on deposit at Vernad. An anonymous collector holds the main mass. |
from The
Meteoritical Bulletin, no. 95, Meteoritics & Planetary Science 44,
429-462 (2009).Dhofar 1443OmanFind: 12 April 2001 Lunar (anorthositic breccia) History: On April 12, 2001, one stone was found by an anonymous finder in the Dhofar region, Oman. Some years later three further tiny fragments were found within a few feet. The total mass of all stones is 36.7 g. Physical characteristics: The rock is slightly weathered and relatively dark in hand specimen. Petrography and mineralogy (A. Bischoff, IfP and E. H. Haiderer, Vienna): typical anorthositic breccia with light anorthositic clasts and abundant impact melt clasts embedded within a tough, partially molten matrix. This mostly devitrified matrix contains abundant vesicles and schlieren. Based on the optical appearance the rock has some similarities with Dhofar 081, however, the coordinates do not favor pairing. Mineral compositions: feldspar ranges from An83–98 with a mean of An94.8 ± 3.5; pyroxene is Fs12–49; mean: Fs30 ± 9; and olivine is Fa19–52; mean: Fa35.5 ± 9. Classification: Lunar (anorthositic breccia). Type specimens: 7.4 g and one polished thin section (IfP, Mün); an anonymous collector holds the main mass. |
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