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Dhofar 1671 | |||||||||||||||||||||||||||||||||||
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Basic information | Name: Dhofar 1671 This is an OFFICIAL meteorite name. Abbreviation: Dho 1671 Observed fall: No Year found: 2011 Country: Oman Mass: ![]() | ||||||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 31 approved meteorites classified as R3-6. [show all] Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3) | ||||||||||||||||||||||||||||||||||
Comments: |
Approved 21 Sep 2012 Revised 5 Dec 2016: Reclassified | ||||||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 101:
Dhofar 1671 (Dho 1671) 18°52’10.5"N, 54°13’46.4"E Zufar, Oman Found: Jan 2011 Classification: Carbonaceous chondrite (CV3) Petrography: (P. Strickland, UAb). Approximately 45 vol% chondrules, 40 vol% matrix, 8 vol% metals/opaques, 5 vol% subhedral-euhedral olivine grains, and 2 vol% CAIs + AOAs. Chondrules (~1 mm average diameter) are dominantly porphyritic but also display barred olivine, cryptocrystalline and radial pyroxene textures. Chondrule mineralogy consists of olivine, orthopyroxene, and Ca-pyroxene; glass appears to be absent or altered. Most chondrules consisting of compositionally zoned olivine grains are surrounded by fine-grained accretionary rims, however there are some that display a multi-layered rim consisting of a fine-grained accretionary rim and a Fe-Ni metal rim. A CAI, found within the forsterite core of a zoned euhedral olivine, is composed of fassaitic pyroxene and plagioclase. Irregular fractures, minor undulatory extinction, and very rare planar fractures indicate weak shock deformation. Very minor rusty staining and the lack of visible oxidation of metals indicates low weathering. Geochemistry: (C. Herd and P. Strickland, UAb) Olivine Fa20.6±14.9 (n=115); low-Ca pyroxene Fs9.4±6.9Wo2.8±2.6 (n=17); CAI Plagioclase Ab64 An34 Or2; fassaite (all wt%) SiO2=47.0, TiO2=1.07, Al2O3=13.5, FeO=0.22, MgO=15.0, CaO=22.0. Classification: Carbonaceous chondrite (CV), Type 3, reduced subgroup. Classified based on petrographic and geochemical data relative to other known CV chondrites. Specimens: 23.9 g type specimen, including polished thin section, are on deposit at UAb. Remainder at SQU. Writeup from MB 105: Dhofar 1671 (Dho 1671) 18° 52' 10"N, 54° 13' 46"E Zufar, Oman Find: 2011 Classification: Carbonaceous chondrite (R3-6) History: A comparison of Dhofar 1671 with the CV and R chondrites indicates that Dhofar 1671 is not a CV3 chondrite. Physical characteristics: (S. Nasir, SQU) Overall texture is brecciated, showing light and dark clasts within a fine-grained matrix. Petrography: (C. Herd and S. Kampel. UAb, S. Nasir, SQU) Re-examination of petrographic thin sections shows that the proportions of opaque minerals and CAIs + AOAs are lower than originally estimated (< 1 vol% opaques, consisting primarily of pyrrhotite and pentlandite; < 0.1 vol% CAIs + AOAs); the originally described CAI is plagioclase and fassaitic pyroxene within an aluminum-rich chondrule. Clasts include lithic fragments of variable petrologic type. Chondrule sizes range up to >1 mm in some cases; however, most are <1 mm (0.45±0.20 mm, n = 43). Geochemistry: (A. Ali and I. Jabeen, UWO) Analyses of four untreated bulk materials by laser-assisted fluorination provided, respectively, δ17O 4.740, 5.354, 5.245, 5.018; δ18O 4.283, 4.713, 4.291, 4.402; Δ17O 2.506, 2.895, 3.005, 2.722 per mil. (C. Herd, UAb and T. Theye, UStutt): Chondrule olivine Fa21.2±14.7, range Fa0.3-48.8 (n=112); low-Ca pyroxene Fs8.2±6.7Wo2.4±2.5 (n=21); high-Ca pyroxene Fs11.1±0.8Wo44.9±1.8 (n=4). Classification: Petrography (including texture and average chondrule size) and bulk oxygen isotopic composition indicate that Dhofar 1671 is an R3-6 chondrite. | ||||||||||||||||||||||||||||||||||
Data from: MB101 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||||||||
Institutions and collections |
UWO: University of Western Ontario, Department of Earth Sciences, BGS 1026, 1151 Richmond St. N, London, Ontario, Canada N6A 5B7, Canada (institutional address; updated 18 Jul 2015) UAb: 1-26 Earth Sciences Building, University of Alberta, Edmonton, AB, T6G 2E3, Canada, Canada; Website (institutional address; updated 17 Oct 2011) SQU: Sultan Qaboos University, College of Science, Earth Sciences Department, P.O. Box 36 Code 123 AlKhoud, Oman (institutional address; updated 5 Oct 2014) UStutt: Universität Stuttgart, Institut für Mineralogie und Kristallchemie, Azenbergstraße 18, D-70174 Stuttgart , Germany (institutional address; updated 3 Aug 2014) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 101, MAPS 50, 1661, September 2015 Published in Meteoritical Bulletin, no. 105, MAPS 52, 2411, September 2017. http://onlinelibrary.wiley.com/doi/10.1111/maps.12944/full
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Geography:![]() |
Statistics: This is 1 of 2168 approved meteorites from Zufar, Oman (plus 22 unapproved names) This is 1 of 4002 approved meteorites from Oman (plus 434 unapproved names) | ||||||||||||||||||||||||||||||||||
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