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Northwest Africa 7514 | |||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 7514 This is an OFFICIAL meteorite name. Abbreviation: NWA 7514 Observed fall: No Year found: 2005 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||
Classification history: |
This is 1 of 40 approved meteorites classified as R5. [show all] Search for other: Rumuruti chondrites, Rumuruti chondrites (type 4-7) | ||||||||||||||||||||||||
Comments: |
Approved 18 Nov 2012 Revised 28 Nov 2012: corrected mass | ||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 101:
Northwest Africa 7514 (NWA 7514) (Northwest Africa) Found: Sept 2005 Classification: Rumuruti chondrite (R5) History: Originally thought not to be a meteorite, and was received by the main mass holder as a gift from a meteorite collector in September 2005. Samples were given to Cascadia in June 2012 and subsequently recognized to be a meteorite. Physical characteristics: The specimen contains large facets, regmaglypts, and is largely covered by a translucent fusion crust that appears olive gray. In places slight protrusions <1 mm high and ~1-4 mm across are present and covered by crust. A few small broken faces have a brownish weathering patina. A cut face shows a nearly featureless interior with an overall color more gray than that of the fusion crust. Petrography: (A. Ruzicka and M. Hutson, Cascadia) In thin section the rock shows chondritic texture with a transparent matrix and significant chondrule-matrix integration. Indistinct microporphyritic and barred olivine chondrules are visible; a clast of olivine microporphyry ~4.5 × 3.6 mm across is the largest feature. The rock consists primarily of olivine, with subequal plagioclase and Ca-pyroxene, and accessory chromite, Cl-apatite, pentlandite, and pyrrhotite. Feldspar grain size (length) = 37±18 μm, n=199. Olivine grains show diverse shock characteristics split roughly evenly between stages S2, S3, and S4. Geochemistry: Phases are generally equilibrated (all values atomic): olivine Fa38.2±0.5, n=32; plagioclase Ab84.4±2.0Or5.7±0.9An9.9±1.8, n = 20; Ca-pyroxene Wo40.1±2.5Fs15.4±1.9, n = 20; chromite [Fe/(Fe+Mg)] = 0.94±0.05, [Cr/(Cr+Al)] = 0.81±0.03, n=14; Ni-rich pentlandite (approximately Fe0.49Ni0.51S1.0) and S-rich pyrrhotite (approximately Fe0.81 Ni0.01S1.0). Oxygen isotope composition: (R. Greenwood, OU) δ17O = 5.74, δ18O = 5.04, Δ17O = 3.12 (all per mil). Classification: Rumuruti chondrite (R5). Mineralogy, mineral chemistry, and O-isotopic composition consistent with R chondrite group. Specimens: 40.3 g, two thick slices, and one thin section at Cascadia. Main mass, TStout. | ||||||||||||||||||||||||
Data from: MB101 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||
Institutions and collections |
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011) OU: Planetary and Space Sciences Department of Physical Sciences The Open University Walton Hall Milton Keynes MK7 6AA United Kingdom, United Kingdom (institutional address; updated 8 Dec 2011) TStout: Tim Stout, P.O. Box 181, Hillsboro, Oregon 97123, United States (private address; updated 15 Apr 2013) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 101, MAPS 50, 1661, September 2015
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Photos: |
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |