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Lunar Meteorites: Dhofar 303, 305, 306, 307, 309, 310, 311, 489, 730, 731, 908, 909, 911, 950, & 1085 (paired stones)Oman |
Slabs of Dhofar stones 303, 305, 306, 309, 911 (2x), and 1085, with millimeter ticks for scale. The gray areas are veins of impact-melt glass that has the same composition as the pink clasts. The clasts are pink from hematite staining (terrestrial weathering). (Photo by Randy Korotev. Click on image for enlargement.)
(Photos by Randy Korotev. Click on image for enlargement.)
Note how the rounded vesicles are restricted to the glassy veins of impact melt (gray). (Photos by Randy Korotev. Click on image for enlargement.) |
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Dhofar 1085 in the field. (Photo courtesy of Siegfried Beutel and Haberer-Meteorites.)  A sawn slab of Dhofar 1085 in the lab. (Photo by Randy Korotev) |
from The
Meteoritical Bulletin, No. 86, Meteoritics & Planetary Science
37, A157-A184 (2002)
Dhofar 30319°19.8' N, 54°47.0' EOman Found 2001 June 28 Lunar meteorite (anorthositic impact melt conglomerate) A light grey stone weighting 4.15 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad; L. Taylor, UTenn): fusion crust is absent; meteorite has a typical conglomerate texture; rounded lithic clasts are cemented by a very fine-grained impact melt matrix; clasts of impact melt breccias are most abundant and show commonly breccia-in-breccia textures; primary igneous rocks and granulites are rare and have mainly anorthositic and troctolitic compositions; feldspar, An94-99; orthopyroxene, Wo1-5En19-89; clinopyroxene, Wo6-46En29-70; olivine, Fo48-88 (Fe/Mn ~87 atom%); accessory minerals are Ti-rich chromite, ilmenite (3-6 wt% MgO), Al-Cr-Zr-rich armalcolite, rutile, troilite, and FeNi metal (1-37 wt% Ni; 0.2-2.3 wt% Co); composition of the impact melt matrix is SiO2 = 44.0, TiO2 = 0.15, Al2O3 = 29.8, Cr2O3 = 0.06, FeO = 3.17, MnO = 0.06, MgO = 4.91, CaO = 17.0, Na2O = 0.34, K2O = 0.01, P2O5 = 0.03 (wt%); the stone is moderately weathered; celestite, barite, gypsum, calcite and Fe hydroxides are present. The conglomerate texture and degree of weathering distinguish Dhofar 303 from Dhofar 302 and Dhofar 081/280, which were found nearby. However the meteorites may be paired. Specimens: type specimen, 0.85 g plus a thin section, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 30519°19.8'N, 54°47.0'EOman Found 2001 June 28 Lunar meteorite (anorthositic impact melt breccia) Lunar meteorite (anorthositic impact melt breccia) A light-grey stone weighing 34.11 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad, L. Taylor, UTenn): fusion crust is absent; the meteorite is an impact melt breccia consisting of mineral fragments and lithic clasts set within fine-grained, well-crystallized impact-melt matrix; clasts of impact melt breccias are most common; granulites and possible igneous rocks are rare and have mainly anorthositic and troctolitic compositions; orthopyroxenite clasts are present; feldspar, An87-98; orthopyroxene, Wo1-5En40-88; clinopyroxene; Wo6-48En30-70; olivine, Fo44-90 (Fe/Mn = 94 at); accessory minerals are Ti-rich chromite, Cr-pleonaste, ilmenite (1-8 wt % MgO), armalcolite, troilite, and FeNi metal (17-32 wt% Ni; 1.3-2.3 wt% Co); composition of the impact-melt matrix is (wt%) SiO2 = 43.9, TiO2 = 0.16, Al2O3 = 28.5, Cr2O3 = 0.10, FeO = 3.69, MnO = 0.07, MgO = 6.08, CaO = 15.9, Na2O = 0.36, K2O = 0.02, P2O5 = 0.04 (wt%); the stone is moderately weathered; calcite, celestite, gypsum, and Fe hydroxides are present. Dhofar 305 is close to Dhofar 303, which was found nearby, in degree of weathering, mineral chemistry, and matrix composition. The meteorites may be paired but they are very different in texture. Pairing with Dhofar 081/280, 302, 306 and 307 is also possible. Specimens: type specimens of 7 g, and a thin section, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 30619°19.7'N, 54°47.1'EOman Found 2001 June 29 Lunar meteorite (anorthositic impact melt breccia) A light-grey stone weighing 12.86 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad, L. Taylor, UTenn): fusion crust is absent; the meteorite is an impact melt breccia consisting from mineral fragments and lithic clasts cemented by fine-grained impact-melt matrix; clast population is dominated by impact melt breccias; granulites and cataclastic igneous rocks of anorthositic, troctolitic and noritic compositions are present; devitrified glass fragments occur also; a characteristic feature of the lithic clast population is abundant high mg# lithologies; feldspar, An93-98; orthopyroxene, Wo1-5En50-90; clinopyroxene; Wo10- 48En30-75, olivine, Fo48-94 (Fe/Mn = 87 at); accessory minerals are Ti-rich chromite, Cr-pleonaste, ilmenite (3-8 wt% MgO), armalcolite, silica, Ca-phosphate, troilite, and FeNi metal (7-68 wt% Ni, 0.3-3.4 wt% Co); composition of the impact-melt matrix is SiO2 = 44.0, TiO2 = 0.15, Al2O3 = 27.2, Cr2O3 = 0.12, FeO = 4.00, MnO = 0.05, MgO = 7.55, CaO = 15.5, Na2O = 0.33, K2O = 0.04, P2O5 = 0.07 (wt%); the stone is moderately weathered; celestite, calcite and Fe hydroxides are present. Dhofar 306 is different in texture and mineral chemistry from Dhofar 081/280, 302, 303, 305 and 307, which were found nearby. However the meteorites may be paired. Specimens: type specimen, 2.6 g and a thin section, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 30719°19.7'N, 54°46.9'EOman 2001 April 14 Lunar meteorite (anorthositic impact melt breccia) A light-grey stone weighing 50 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad, L. Taylor, UTenn): fusion crust is absent; the meteorite is an impact melt breccia; fine-grained impact melt is most abundant; mineral fragments and rare lithic clasts of anorthositic, troctolitic, and gabbro- noritic compositions occur in the impact-melt matrix; the presence of rare dunite fragments is a characteristic feature of the meteorite; glass veins are common; feldspar, An89-98; orthopyroxene, Wo1-5En50- 90; clinopyroxene; Wo6-48En40-75;, olivine, Fo38-94 (Fe/Mn = 92 at); accessory minerals are Ti-rich chromite, Cr-pleonaste, ilmenite (2-6 wt % MgO), troilite, and FeNi metal (8-49 wt% Ni, 0.3-2.0 wt% Co); composition of the glass veins is SiO2 = 43.8, TiO2 = 0.09, Al2O3 = 30.8, Cr2O3 = 0.09, FeO = 2.58, MnO = 0.05, MgO = 4.06, CaO = 17.3, Na2O = 0.36, K2O = 0.01, P2O5 = 0.02 (wt%); the stone is moderately weathered; calcite, gypsum, celestite, barite, and Fe hydroxides are present. Dhofar 307 is most similar in texture and mineral chemistry to Dhofar 305, found nearby. The meteorites are likely to be paired. Pairing with Dhofar 081/280, 302, 303, and 306 is also possible. Specimens: type specimen, 10 g and a thin section, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 30919°19.6' N, 54°47.3' EOman 2002 January 14 Lunar meteorite (anorthositic impact melt breccia) A grey, partly fusion-crusted 81.3 g stone was found in the Dhofar region of Oman. Classification and mineralogy (S. Demidova, Vernad; G. Kurat, NHMV): the meteorite is a clast-poor impact melt breccia; mineral fragments and lithic clasts are embedded in a matrix of devitrified glass. The clast population is dominated by granulite clasts of mainly anorthositic and troctolitic composition; fragments of possible pristine rocks and single mineral fragments are less common. Mineral compositions: plagioclase An93-98Or0.1-0.4; olivine Fo75-89 (atomic Fe/Mn ~79); orthopyroxene En80-86Wo2-5; clinopyroxene En46-82Wo5-46; accessory minerals are Ti-poor chromite and Cr-pleonaste, ilmenite (4-9 wt% MgO), troilite, and FeNi metal. The composition (wt%) of the impact melt matrix is MgO 6.2, CaO 16.1, Al2O3 29.1, SiO2 44.3, FeO 3.1; terrestrial weathering is not significant, although celestite and calcite are present in cracks. Dhofar 309 is different in texture and mineral chemistry from Dhofar 081/280, 302, 303, 305, 306, 310 found nearby. However, the meteorites may be paired. Specimens: 16.5 g plus two thin sections, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 31019°19.7' N, 54°47.1' EOman 2002 January 15 Lunar meteorite (anorthositic impact melt breccia) A grey 10.8 g stone was found in the Dhofar region of Oman. Classification and mineralogy mineralogy (S. Demidova, Vernad; G. Kurat, NHMV): fusion crust is almost absent; the meteorite is a fragmental regolith breccia containing numerous mineral fragments and clasts of feldspathic rocks embedded in a devitrified glassy matrix; clasts of granulites and possible igneous rocks are abundant and have mainly anorthositic and troctolitic-noritic compositions, impact melt breccias and pyroxenitic clasts are also present; plagioclase An96-99Or0.1-0.2; olivine Fo44-86 (atomic Fe/Mn ~79); orthopyroxene En59-88Wo1-5; clinopyroxene En33-77Wo5-47; accessory minerals are Ti-rich chromite, ulvöspinel, pleonaste, ilmenite (2-7 wt% MgO), armalcolite, silica, troilite, FeNi metal; composition of the impact melt matrix is MgO 4.8, CaO 18.5, Al2O3 29.1, SiO2 43.5, FeO 3.0 (wt%); the stone is moderately weathered: calcite and gypsum veins and celestite inclusions are present. Dhofar 310 was found closely to Dhofar 302, 303, 305, 306, 307, 081/280 and may be paired with some of these meteorites. Specimens: 2.5g plus a thin section, Vernad; main mass with anonymous finder. finder. |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 31119°19.6' N, 54°47.0' EOman 2001 April 14 Lunar meteorite (anorthositic impact melt breccia) A small light-grey stone weighing 4 g was found in the Dhofar region of Oman. Mineralogy and classification (S. Demidova, Vernad; L. Taylor, UTenn): fusion crust is absent; mineral fragments and rounded lithic clasts occur within a fine-grained to cryptocrystalline impact-melt matrix; the lithic clast population comprises impactmelt breccias, as well as cataclastic granulitic and igneous rocks of anorthositic and troctolitic compositions; clasts of impact-melt breccias are most abundant and typically show breccia-in-breccia textures; feldspar, An95-98; orthopyroxene, Wo2-5En45-85; clinopyroxene; Wo6-45En40-74, olivine, Fo57-88 (Fe/Mn ~91 at); accessory minerals include: Cr-pleonaste, Al-chromite, troilite, and FeNi metal (3-27 wt% Ni; 0.2-1.9 wt% Co); the stone is moderately weathered; calcite, gypsum, celestite, barite, and Fe hydroxides are present. Dho 311 was found 25m from Dho 280, but the meteorites are very different in weathering grade and lithology. Dho 311 is most similar in texture and mineral chemistry to Dho 303 found nearby. The meteorites may be paired. Pairing with Dho 302, 305, 306, 307, 309, 310, 730 and 731 is also possible. Specimens: type specimen of 1.7 g plus a thin section, Vernad; main mass with anonymous finder. |
from The
Meteoritical Bulletin, No. 86, Meteoritics & Planetary Science
37, A157-A184 (2002)
Dhofar 48919°25' N, 54°35' EOman Found 2001 August 11 Lunar meteorite (feldspathic crystalline matrix breccia) One 34.4 g stone was found in the Dhofar region of Oman. Mineralogy and classification (H. Takeda, Chiba, T. Ishii and M. Ohtsuki UTok): A feldspathic fragmental breccia consisting of clasts of various lithologies embedded into a fine-grained crystalline matrix (crystals up to 0.04 mm in length). Clasts include cataclastic feldspars up to 1.8 x 0.6 mm in size, plus dark fine-grained impact melt breccia 3.3 x 2.3 mm in size with feldspar fragments. Plagioclase compositions of An95-97 are within the range of lunar anorthites. Pyroxene crystals in plagioclase and crystalline matrix range from En75Fs21Wo4 to En85Fs10Wo5 with FeO/MnO (wt%) =57. Olivine: Fa15 to Fa24 with FeO/MnO (wt%) == 78. Fine Ca carbonate veins penetrate into the specimen. Unlike known lunar meteorites, this lunar rock is a feldspathic crystalline matrix breccia. The most Mg-rich pyroxene is more Mg-rich than those of common lunar regolith breccias and similar to those of 60019, an Apollo 16 breccia containing poikilitic clasts. This lunar meteorite differs from other known lunar meteorites from the Dhofar region, which are either feldspathic regolith breccias or fragmental breccias. Specimens: type specimen: 6 g, NSMT; 0.42 g plus two polished thin sections, Chiba; main mass with anonymous finder. |
Author's note about Dhofar 489Dhofar 489 was found 24 km away from the other meteorites listed here but it looks similar to the others in slab view. The petrographic description is not significantly different from those of the others, considering that different petrographers described the stones and the thin sections used to classify the meteorites are too small with respect to the grain size of the clasts. I have analyzed samples of the stones pictured above by neutron activation analysis and obtain results very similar to those of Karouji et al. (2004) for Dhofar 489 (we haven't yet analyzed our sample of 489 pictured above). The composition of all of these stones is distinctly different* from those of any other lunar meteorite. On the basis of the similarities to each other and mutual dissimilarity to other lunar meteorites, it is highly unlikely that Dhofar 489 is from a different fall than Dhofar 303. 305, 306, etc. I assume here that they are all paired until definitive evidence to the contrary is available. * high Cr/Sc, low REE, low Th/REE, low siderophile
elements |
from The
Meteoritical Bulletin, No. 87, Meteoritics & Planetary Science
38, A189-A248(2003)
Dhofar 73019°19.5' N, 54°47.5' EOman 2002 November 9 Lunar meteorite (anorthositic impact-melt breccia) A light-grey stone weighing 108 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad; L. Taylor, UTenn): fusion crust is absent; lithic clasts and mineral fragments set within a fine-grained impact-melt matrix; the lithic clast population is dominated by impact-melt breccias and cataclastic granulitic and igneous rocks of anorthositic and troctolitic compositions; rare dunite fragments are present; feldspar, An86-98; orthopyroxene, Wo2-4En56-85; clinopyroxene; Wo6-46En14-71; olivine, Fo55-92 (Fe/Mn ~86 at). Accessory minerals include: chromite, Crpleonaste, armalcolite, ilmenite, silica, troilite, and FeNi metal (6-48 wt% Ni; 1-2.4 wt% Co); the stone is moderately weathered; calcite, gypsum, celestite, barite, and Fe hydroxides are present. The meteorite may be paired with Dho 302, 303, 305, 306, 307, 309, 310, 311 and 731 found nearby. Specimens: type specimens of 22 g, and a thin section, Vernad; main mass with anonymous finder. |
from
The Meteoritical
Bulletin, No. 87, Meteoritics & Planetary Science 38,
A189-A248(2003)
Dhofar 73119°20.0' N, 54°47.7' EOman Found 2001 June 28 Lunar meteorite (anorthositic impact melt breccia) A light-grey stone weighing 36 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad; L. Taylor, UTenn): fusion crust is absent; lithic clasts and mineral fragments occur within a fine-grained impact-melt matrix; the lithic clast population consists mainly of impact-melt breccias of anorthositic and troctolitic compositions; feldspar, An95-97; orthopyroxene, Wo2-5En53-85; clinopyroxene; Wo6-45En30-81, olivine, Fo52-87 (Fe/Mn ~84 at). Accessory minerals include: Cr-pleonaste, chromite, ilmenite, troilite and FeNi metal (0.5-66 wt% Ni; 0.2-2 wt% Co); Crpleonast is most common; the stone is moderately weathered; calcite, gypsum, celestite, barite, smectite, and Fe hydroxides are present. Dho 731 may be paired with Dho 302, 303, 305, 306, 307, 309, 310, 311, and 730. Specimens: type specimens of 7.5 g, and a thin section, Vernad; main mass with anonymous finder. |
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from The
Meteoritical Bulletin, no. 89, Meteoritics & Planetary Science
40, A201-A263 (2005)
Dhofar 95019°19.5' N, 54°46.9' EOman 2003 November 11 Lunar meteorite (feldspathic impact melt breccia) A grey stone weighing 21.7g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad., Th. Ntaflos, University of Vienna): fusion crust is absent. The meteorite is an impact melt breccia with mineral fragments and lithic clasts cemented by a glassy impact melt matrix. The lithic clast population includes mainly granulitic rocks of anorthositic, troctolitic, gabbro-noritic and gabbro-anorthositic compositions. The sample contains abundant veins of glass. Mineral compositions are as follows: feldspar, An92-98Or0-0.3; orthopyroxene, Wo0.4-5En55-91; clinopyroxene; Wo5-44En30-72; olivine, Fo52-92 (Fe/Mn ˜ 85 at); accessory phases are Al-rich enstatite, Mg,Al-rich spinel, pleonaste, Al-rich chromite, ilmenite (1.1-8.5 wt.% MgO), armalcolite, silica, troilite, and FeNi metal (0.6-8 wt.% Ni; 0.4-1.1 wt.% Co). Matrix glass composition (wt.%): SiO2 43.9, TiO2 0.05, Al2O3 33.1, FeO 1.08, MgO 1.77, CaO 18.6, Na2O 0.37. The stone contains moderately weathered gypsum, celestite, and Fe hydroxides. The meteorite may be paired with Dho 302, 303, 305, 306, 307, 309, 310, 311, 730, 731 found nearby. Specimens: type specimens of 4.8g and a thin section, Vernad. The main mass is held by an anonymous finder. |
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