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Lavras do Sul | |||||||||||||||||||||||||||||
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Basic information | Name: Lavras do Sul This is an OFFICIAL meteorite name. Abbreviation: There is no official abbreviation for this meteorite. Observed fall: No Year found: 1985 Country: Brazil Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 8604 approved meteorites (plus 4 unapproved names) classified as L5. [show all] Search for other: L chondrites, L chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||
Comments: | Approved 25 Aug 2010 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 99:
Lavras do Sul 30°48’S, 53°54’W Rio Grande do Sul, Brazil Found: 1985 Classification: Ordinary chondrite (L5) History: A single mass weighing ~1 kg was found in a pebbly streambed near the town of Lavras do Sul by Prof. Picada of the Geosciences Institute, UFRGS. He gave it to his colleague Dr. Ary Roisemberg. Geologist Heinrich Frank contacted Dr. Hardy Grunewaldt after seeing the specimen in one of Dr. Roisemberg’s lectures Physical characteristics: The 10 x 5 x 6 cm stone is completely fusion crust-covered . The interior shows brown spots due to weathering. The sample investigated in MNRJ is 67 g. Petrography: (M.E.Zucolotto, MNRJ; L.L. Antonello, CBPF) The meteorite shows a few well-defined chondrules and fragments dispersed in a recrystallized matrix. The best-preserved chondrules are RP and BO. The chondrule sizes vary, mostly between 0.5 to 2.0 mm. Opaque phases are kamacite, taenite, troilite and tetratenite. The latter is observed as a thin layer that borders taenite and plessite. Kamacite is mostly polycrystalline and in some cases the plessite shows pearlitic structure bordered by tetrataenite. Sulfides are abundant and are mainly present as single grains. In places small plagioclase grains (partially isotropic) are observed. Some oxide veins as well as iddingsite penetrate along olivine fractures. Minor oxide is present around some metal grains. Melt pockets are scarce and small. Olivine grains have rims with planar fractures but clean cores, in which weakly mosaic and/or undulatory extinction is observed. Geochemistry: (M.E.Varela, ICATE; R. Scorzelli, CBPF) Mean compositions are olivine (Fa25) and low-Ca pyroxene (Fs22.6). Classification: Ordinary chondrite (L5); S3-4; weathering W1 Specimens: 57 g plus three thin sections are on deposit in MNRJ. Main mass with Dr. A. Roisemberg, UFRGS. | ||||||||||||||||||||||||||||
Data from: MB99 Table 0 Line 0: |
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Institutions and collections |
MNRJ: Museu Nacional, Quinta da Boa Vista, Rio de Janeiro, CEP 20940-040, Brazil (institutional address; updated 26 Dec 2011) CBPF: Centro Brasiliero de Pesquisas Fisicas, Rua X. Sigaud 150, 22220-030 Rio de Janeiro, Brazil (institutional address) ICATE: Instituto de Ciencias Astronomicas de la Tierra y del Espacio Av. España Sur 1512 – San Juan , Argentina; Website (institutional address; updated 31 Oct 2021) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, No. 99, April 2012, MAPS 47, E1-E52 (2012) [published online only]
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Photos: |
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Geography:![]() |
Statistics: This is 1 of 12 approved meteorites from Rio Grande do Sul, Brazil (plus 1 unapproved name) This is 1 of 87 approved meteorites from Brazil (plus 6 unapproved names) (plus 7 impact craters) | ||||||||||||||||||||||||||||
Proximity search: |