The main mass of 272.3 kilograms (600 lb) was found during a survey in June 1967 by geologist F. A. Mednikov. The mass was a triangular-shaped thumbprinted meteorite lying among the stones of the brook bed. A second specimen of 51 kilograms (112 lb) was found with a mine detector at a distance of 20 m from the first in October 1967 by I. H. Markov. The main mass was turned over to the Academy of Sciences of the USSR.
During a new expedition in 2004, Dmitri Kachalin recovered about 50 kilograms (110 lb) of new material. Remarkably, about 20% of the new specimens were found to contain olivine crystals,[2] and so revealed the silicated nature of the meteorite. The pallasitic structure was not previously discovered during studies on small metal-only sections of the original mass.
Composition and classificationedit
Seymchan, Pallasite, PMG.
Seymchan belongs to Main Group pallasites, but it is considered anomalous due to its high Iridium content.[3] Before the discovery of its pallasitic structure it had been classified as IIE anomalous coarse octahedrite. Seymchan is considered a stable and rust-resistant pallasite.
Specimensedit
Due to the heterogeneous structure of Seymchan, there are two types of specimens: with or without olivine crystals. It is worthy to note that the specimen pictured to the left shows an interesting, seldom seen feature of iron meteorites. The Widmanstätten pattern on the left hand side of the specimen is visibly bent. This is caused by the shearing of the meteorite as it broke up during atmospheric entry and serves as testimony of the violent experience a meteor is subject to as it falls through the atmosphere.
Media related to Seymchan meteorite at Wikimedia Commons
Meteoritical Bulletin Database
November 15, 2023
seymchan, meteorite, seymchan, pallasite, meteorite, found, river, hekandue, left, tributary, river, yasachnaya, magadan, district, russia, near, settlement, seymchan, june, 1967, seymchanan, olivine, free, portion, seymchantypestony, ironstructural, classific. Seymchan is a pallasite meteorite found in the dry bed of the river Hekandue a left tributary of river Yasachnaya in the Magadan district Russia near the settlement of Seymchan in June 1967 SeymchanAn olivine free portion of SeymchanTypeStony ironStructural classificationCoarse octahedriteClassPallasiteGroupMain Group PallasiteComposition9 15 Ni 24 6 ppm Ga 68 3 ppm Ge 0 55 ppm Ir CountryRussiaRegionMagadan OblastCoordinates62 54 N 152 26 E 62 900 N 152 433 E 62 900 152 433 1 Observed fallNoFound dateJune 1967TKWabout 380 kilogramRelated media on Wikimedia Commons Contents 1 History 2 Composition and classification 2 1 Specimens 3 See also 4 References 5 External linksHistory editThe main mass of 272 3 kilograms 600 lb was found during a survey in June 1967 by geologist F A Mednikov The mass was a triangular shaped thumbprinted meteorite lying among the stones of the brook bed A second specimen of 51 kilograms 112 lb was found with a mine detector at a distance of 20 m from the first in October 1967 by I H Markov The main mass was turned over to the Academy of Sciences of the USSR During a new expedition in 2004 Dmitri Kachalin recovered about 50 kilograms 110 lb of new material Remarkably about 20 of the new specimens were found to contain olivine crystals 2 and so revealed the silicated nature of the meteorite The pallasitic structure was not previously discovered during studies on small metal only sections of the original mass Composition and classification edit nbsp Seymchan Pallasite PMG Seymchan belongs to Main Group pallasites but it is considered anomalous due to its high Iridium content 3 Before the discovery of its pallasitic structure it had been classified as IIE anomalous coarse octahedrite Seymchan is considered a stable and rust resistant pallasite Specimens edit Due to the heterogeneous structure of Seymchan there are two types of specimens with or without olivine crystals It is worthy to note that the specimen pictured to the left shows an interesting seldom seen feature of iron meteorites The Widmanstatten pattern on the left hand side of the specimen is visibly bent This is caused by the shearing of the meteorite as it broke up during atmospheric entry and serves as testimony of the violent experience a meteor is subject to as it falls through the atmosphere See also editGlossary of meteoriticsReferences edit Meteoritical Bulletin Database Seymchan Meteorites Studies Seymchan van Niekerk 2007External links edit nbsp Media related to Seymchan meteorite at Wikimedia Commons Meteoritical Bulletin Database Retrieved from https en wikipedia org w index php title Seymchan meteorite amp oldid 1142870339, wikipedia, wiki, book, books, library,
