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Northwest Africa 7030 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 7030 This is an OFFICIAL meteorite name. Abbreviation: NWA 7030 Observed fall: No Year found: 2011 Country: (Northwest Africa) Mass: 224 g | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 102 approved meteorites classified as LL7. [show all] Search for other: LL chondrites, LL chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||||
Comments: | Approved 21 Jun 2014 | ||||||||||||||||||||||||||||||
Writeup |
Writeup from MB 103:
Northwest Africa 7030 (NWA 7030) (Northwest Africa) Purchased: 2011 Oct Classification: Ordinary chondrite (LL7) History: Purchased by GHupé in October 2011 from a dealer in Zagora, Morocco. Physical characteristics: A fresh stone (224 g) covered by black, glossy fusion crust, except at one end where the slightly stained, greenish-gray interior is visible. There are two distinct lithologies present and the minor lithology is distinctly green in color. Petrography: (A. Irving and S. Kuehner, UWS) The major lithology consists of an aggregate of olivine, clinopyroxene, sodic plagioclase, chromite, troilite and taenite. A subordinate lithology is a very fresh, medium-grained, igneous-textured achondrite composed mostly of olivine and orthopyroxene with ~8 vol.% intercumulus potassium feldspar, albitic plagioclase (some with exsolved K-feldspar lamellae), clinopyroxene, and accessory taenite, troilite, chromite and kamacite. The latter lithology contains much less troilite than the major lithology. Geochemistry: Olivine (Fa29.1-29.3, N = 4), orthopyroxene (Fs23.4-23.7Wo3.7-2.8), clinopyroxene (Fs11.6-12.6Wo39.8-39.2), plagioclase (An12.6-13.9Or2.2-2.3). Oxygen isotopes (R. Tanaka, OkaU): analyses of acid-washed subsamples by laser fluorination gave (all in per mil) δ17O = 4.414, 4.357, δ18O = 6.235, 6.059, Δ17O = 1.129, 1.164 (for a TFL slope of 0.527). Bulk composition (R. Conrey, WSU): analysis of clean wire-saw cutting dust representative of the entire specimen by X-ray fuorescence spectrometry gave (in wt.%) SiO2 = 39.7, TiO2 = 0.11, Al2O3 = 2.6, Cr2O3 = 0.56, FeO = 23.11, MnO = 0.35, MgO = 25.9, CaO = 1.92, Na2O = 1.0, K2O = 0.23, P2O5 = 0.18. Classification: Ordinary chondrite (LL7, potassic). There are no chondrules evident in either lithology of this unusual specimen; however, its oxygen isotopic composition and bulk major element composition establish an affinity with LL chondrites. The relatively high abundance of K-feldspar in the green pyroxene-rich lithology is an anomalous feature. Specimens: 20.1 g and one large polished thin section are at UWB. The remaining material is held by GHupé. | ||||||||||||||||||||||||||||||
Data from: MB103 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||||
Institutions and collections |
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012) UWB: University of Washington, Burke Museum of Natural History and Culture, Box 353010 Seattle, WA 98195, United States (institutional address; updated 9 Oct 2023) GHupé: Gregory M. Hupé, 9003 Placid Lakes Blvd., Lake Placid, FL 33852, United States; Website (private address) OkaU: Institute for Study of the Earth's Interior, Okayama University, Misasa Tottori 682-0193, Japan (institutional address) WSU: Washington State University Pullman, WA 99164-2812, United States (institutional address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 103, MAPS 52, 1014, May 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12888/full
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Geography: |
Statistics: This is 1 of 9933 approved meteorites from (Northwest Africa) (plus 1837 unapproved names) |