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Northwest Africa 1982 | |||||||||||||
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Basic information | Name: Northwest Africa 1982 This is an OFFICIAL meteorite name. Abbreviation: NWA 1982 Observed fall: No Year found: 2000 Country: (Northwest Africa) Mass: ![]() | ||||||||||||
Classification history: |
This is 1 of 9 approved meteorites classified as Mesosiderite-C. [show all] Search for other: Class C mesosiderites, Mesosiderites, and Metal-rich meteorites | ||||||||||||
Writeup![]() |
Writeup from MB 88:
Northwest Africa 1982 Morocco Found 2000 Achondrite (ungrouped) A 368 g partially crusted stone was purchased in Rissani in 2001. Classification and mineralogy (T. Bunch and J. Wittke, NAU): cataclastic pyroxenite with randomly dispersed metal grains; partial recrystallization of matrix and along fractures of large (up to 5 mm) orthopyroxene grains. Mineral modes: orthopyroxene, 68 vol.%; metal, 12%; plagioclase. 8%; troilite, 3%; ilmenite, 3%; phosphate, 2% spinels, 2%, and augite, 2%. Opx = Fs28Wo3; kamacite, Ni = 4.8 to 5.4 wt %; taenite, Ni = 31.4 to 36.7%; plagioclase = An90; spinel #1, Al2O3 = 61 wt%, MgO = 21.4%, FeO = 13.2%; spinel #2, Cr2O3 = 35.9%, Al2O3 = 33.0%, MgO = 17.9%, FeO = 13.1%; augite = Fs13Wo43. Oxygen isotope composition is somewhat outside the range of HED and closest to brachinites and IAB-IIICD irons (R. N. Clayton, UChi) : δ18O = +3.78‰, δ17O = +1.47‰, δ 17O = -0.50 ‰. Cosmic ray exposure age (O. Eugster, UBE): of 18.6+-2.0 Ma falls on the major CRE cluster of the HED meteorites. Not paired with NWA 1827 or 1879 mesosiderite C. Shock level, S1. Weathering grade. W1. Specimens: Type specimens 13.8 g, NAU, 11.5 g with O. Eugster, UBE; main mass. Fectay. | ||||||||||||
Data from: MB88 Table 4 Line 111: |
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Plots: | O isotopes: | ||||||||||||
Institutions and collections |
NAU: Geology, Bldg 12
Knoles Dr
Northern Arizona University, Flagstaff, AZ 86011, United States; Website (institutional address; updated 12 Apr 2012) Fectay: Bruno Fectay and Carine Bidaut, La Memoire de la Terre SARL, 39800 Aumont, France; Website (private address) UBE: University of Bern, University of Bern, Hochschulstrasse 4, CH-3012 Bern, Switzerland (institutional address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 88, MAPS 39, A215-A272 (2004)
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |