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Pecora Escarpment 91002 | |||||||||||||||||||||||||||||
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Basic information | Name: Pecora Escarpment 91002 This is an OFFICIAL meteorite name. Abbreviation: PCA 91002 Observed fall: No Year found: 1991 Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)] Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 4 approved meteorites classified as R3.8-6. [show all] Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3) | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from AMN 15(2):
Sample No.: PCA91002 Location: Pecora Escarpment Field Number: 5499 Dimensions (cm): 7.8 x 4.9 x 4.7 Weight (g): 210.2 Meteorite Type: Ungrouped chondrite (similar to ALH85151 and Carlisle Lake)
Macroscopic Description: Robbie Marlow One third of PCA91002 is covered with dull, dark brown fusion crust. Evaporite deposit is present on the interior and exterior surfaces. The interior matrix is fine-grained, dark gray, and contains numerous inclusions which have a wide range of sizes. Sulfides are present.
Thin Section (,8) Description: Brian Mason The section shows numerous polycrystalline silicate clasts (up to 1.2 mm in maximum dimension), some small chondrules (up to 0.5 mm across), and mineral grains in a finely-granular gray matrix. A moderate amount of sulfides is present, much of it as minute grains disseminated through the matrix. No nickel-iron was seen. The meteorite appears to be unweathered. Microprobe analyses show olivine and pyroxene of variable composition. Olivine compositions show a prominent peak at Fa39, with occasionally more magnesian grains (CV FeO is 44). The pyroxene is almost entirely low-Ca: Wo0.3-5, Fs1-28; one grain of diopside, Wo45Fs12, was analyzed. Maskelynite is present in a few clasts. The sulfides are mainly pentlandite, with minor troilite. This meteorite cannot readily be placed in any of the recognized chondrite classes, and hence is recorded as ungrouped. It is very similar to ALH85151 and Carlisle Lake (Geochim. Cosmochim. Acta, v. 53, p. 3035, 1989; v. 55, p. 2657, 1991).
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Data from: MB76 Table 2 Line 4864: |
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Catalogs: |
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References: | Published in Antarctic Meteorite Newsletter 15(2) (1992), JSC, Houston Published in Meteoritical Bulletin, no. 76, Meteoritics 29, 100-143 (1994)
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Geography:![]() |
Statistics: This is 1 of 40719 approved meteorites from Antarctica (plus 4494 unapproved names) | ||||||||||||||||||||||||||||
Proximity search: |