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Northwest Africa 2775 | |||||||||||||||||||
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Basic information | Name: Northwest Africa 2775 This is an OFFICIAL meteorite name. Abbreviation: NWA 2775 Observed fall: No Year found: 2005 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||
Classification history: |
This is 1 of 88 approved meteorites classified as Acapulcoite. [show all] Search for other: Acapulcoite-lodranite family, Acapulcoites, and Primitive achondrites | ||||||||||||||||||
Comments: | Approved 1 Sep 2006 | ||||||||||||||||||
Writeup![]() |
Writeup from MB 91:
Northwest Africa 2775 Algeria Find: 2005 Achondrite (acapulcoite) History and physical characteristics: A dark brown, 222 g, partially crusted stone was purchased in Erfoud, Morocco, in November 2005. Petrography: (J. Wittke and T. Bunch, NAU; A. Irving, UWS) Recrystallized homogeneous, polygonal to subhedral grains <0.8 mm in size. Mineral compositions and geochemistry: Olivine (Fa14.5±0.2; FeO/MnO = 30.5, MnO > 0.02 wt%), orthopyroxene (Fs13.3±0.2Wo3.0; FeO/MnO = 17), diopside (Fs6.8Wo41.9; FeO/MnO = 12), plagioclase (An17.4), Fe,Ni rich metal (Ni = 22.5 wt%). FeS is also observed. Oxygen isotopes: (D. Rumble, CIW) Multiple analyses of different samples of the rock by laser fluorination are δ17O = + 0.78 and + 0.97, δ18O = +2.94 and +3.25, Δ17O = −0.764 and −0.743 (all ‰). Classification: Achondrite (acapulcoite). Type specimen: A 20.1 g sample is on deposit at NAU. Turecki and Reed hold the main mass. | ||||||||||||||||||
Data from: MB91 Table 2 Line 114: |
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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) UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012) CIW: Carnegie Insitution Washington, Geophysical Laboratory, 5251 Broad Branch Rd., NW, Washington DC 20015, United States (institutional address) Reed: Blaine Reed, P.O. Box 1141, Delta, CO 81416, United States; Website (private address) Turecki: Stan Turecki, 5618 Regis Ave., Port Richey, Florida, United States (private address; updated 28 Dec 2010) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 91, MAPS 42, 413-466 (2007)
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Geography: |
Statistics: This is 1 of 9116 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |