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Post Info TOPIC: Ningqiang meteorite
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Title: The Ningqiang Carbonaceous Chondrite and the Origin of Aggregational and Granoblastic Chondrules
Authors: Rubin, A. E., Wang, D., & Kallemeyn, G. W.

Of the four major groups of carbonaceous chondrites, CV3 chondrites exhibit the greatest petrologic variation: the mean apparent diameter of chondrules varies by a factor of 1.8 and the modal abundances of olivine aggregates and refractory inclusions vary by factors of 7 and 3, respectively C1,23. Coarse-grained rims surround 59% of the chondrules in Allende but scarcely 1% of those in Leoville t33. However, CV-chondrite falls show negligible variations in bulk composition. One chip of Grasnaja has refractory lithophile elements at only "0.75~ CV except for very high ("3x CV) Ca C43. Additional CV3 chondrites need to be studied to determine the extent of petrologic and compositional variation.
Ningqiang fell on June 25, 1983 in Ningqiang County, Shaanxi Province, China. Four stones with a total mass of 4.6 kg were recovered. Mineralogic and petrographic features of Ningqiang indicate that it is related to CV chondrites; it is the first CV chondrite to fall since 1969.
Ningqiang contains well-defined chondrules and aggregates embedded in a dark, fine-grained matrix. Its high magnetite/metallic Fe-Ni ratio (6.6) arid the occurrence of awaruite as the principal metal phase imply that Ningqiang belongs to the oxidised CV3 subgroup.

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Blobrana


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Title: The Ningqiang meteorite - Classification and petrology of an anomalous CV chondrite
Authors: Rubin, A. E.; Wang, D.; Kallemeyn, G. W.; Wasson, J. T.

Ningqiang is an anomalous CV chondrite (oxidized subgroup) containing a high abundance of aggregational inclusions (13.7 vol pct) and low abundances of refractory inclusions (1.0 + 1.0 or - 0.5 vol pct) and bulk refractory lithophiles (about 0.82 x CV). Ningqiang may have agglomerated after most refractory inclusions at the nebular midplane had already been incorporated into other objects. Coarse-grained rims surround only about 5 percent of Ningqiang chondrules, compared to about 50 percent in normal CV chondrites. Aggregational inclusions appear to have formed by incipient melting of fine-grained aggregates at relatively low temperatures in the solar nebula, possibly by the mechanism responsible for chondrule formation.

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Blobrana


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The Ningqiang (Stone CV3 Carbonaceous chondrite) meteorite fell in Shaanxi, China, on the 25th June, 1983. 1900 hrs.
A total mass of 4.61 kg was recovered. The main part is now held in the Department of Geology, Nanjing University, China.

32°55'30'N., 105°54'24"E.



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