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Northwest Africa 13738 | |||||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 13738 This is an OFFICIAL meteorite name. Abbreviation: NWA 13738 Observed fall: No Year found: 2020 Country: Algeria Mass: ![]() | ||||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 452 approved meteorites classified as LL3. [show all] Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||||||
Comments: | Approved 13 Feb 2021 | ||||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 110:
Northwest Africa 13738 (NWA 13738) Adrar, Algeria Purchased: 2020 Classification: Ordinary chondrite (LL3) History: John Higgins purchased 9 pieces totaling 430.8 g, sourced from a market in Adrar in June 2020. Physical characteristics: Sample has a tabular shape, an orangish-brown weathered exterior showing abundant close-packed chondrules. A cut face shows the interior contains abundant chondrules set in a brown fine-grained matrix. Petrography: Description and classification (A. Love, App) Sample shows chondritic texture composed of numerous, well-defined, close-packed, unequilibrated chondrules with an avg. apparent diameter 640µm (n=106) set within a fine-grained opaque matrix. The sample contains a rounded clast with dispersed chondrules (~5 vol%, avg. diam. of 317 µm, n=15). Additional minerals are: chromite, troilite, diopside, and Na and Ca-glasses. Geochemistry: Host: Olivine (Fa16.8±10.8 (range Fa0.6-37.7), Cr2O3=0.12±0.06, Fe/Mn=32.7±16.5, n=21); low Ca pyroxene (Fs17.7±11.0Wo1.7±1.1, Fe/Mn=26.6±18.1, n=15); high Ca pyroxene (Fs27.2Wo30.1, Fe/Mn=14.3, n=1). Clast: Olivine (Fa7.6-8.7, Fe/Mn=106.2-34.0, n=2); low Ca Pyroxene (Fs5.0-5.3Wo0.6-0.3, Fe/Mn 10.3-16.4, n=2). Classification: Ordinary Chondrite (LL3, C-S2, W3). Based on chondrule size and magnetic susceptibility, sample is an LL chondrite. Poorly equilibrated mineral compositions, mean and standard deviation of Cr2O3 in Type II chondrules (~3.2) (Grossman and Brearley, 2005), presence of yellow mesostasis in chondrules (3.1/3.2), abundant chondrule glass (<3.3) suggest sample is LL3.2/3.3. Specimens: John Higgins holds the main mass. Three slices weighing a total of 23.09 g and a polished thin section are on deposit at App. | ||||||||||||||||||||||||||||||||
Bibliography: |
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Data from: MB110 Table 0 Line 0: |
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Institutions and collections |
App: Department of Geology, 572 Rivers St., Appalachian State University, Boone, NC 28608, United States (institutional address; updated 7 Mar 2013) |
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Catalogs: |
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References: | Published in Gattacceca J., McCubbin F.M., Grossman J., Bouvier A., Chabot N.L., D'Orazio M., Goodrich C., Greshake A., Gross J., Komatsu M., Miao B., and Schrader D. (2022) The Meteoritical Bulletin, No. 110. Meteorit. Planet. Sci. 1-4
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Geography:![]() |
Statistics: This is 1 of 190 approved meteorites from Adrar, Algeria (plus 1 unapproved name) This is 1 of 1277 approved meteorites from Algeria (plus 29 unapproved names) (plus 4 impact craters) |