A new type of solar-system material recovered from Ordovician marine limestone.
From mid-Ordovician ∼470 Myr-old limestone >100 fossil L-chondritic meteorites have been recovered, representing the markedly enhanced flux of meteorites to Earth following the breakup of the L-chondrite parent body. Recently one anomalous meteorite, Österplana 065 (Öst 65), was found in the same beds that yield L chondrites. The cosmic-ray exposure age of Öst 65 shows that it may be a fragment of the impactor that broke up the L-chondrite parent body. Here we show that in a chromium versus oxygen-isotope plot Öst 65 falls outside all fields encompassing the known meteorite types. This may be the first documented example of an 'extinct' meteorite, that is, a meteorite type that does not fall on Earth today because its parent body has been consumed by collisions. The meteorites found on Earth today apparently do not give a full representation of the kind of bodies in the asteroid belt ∼500 Myr ago.
Astrogeobiology Laboratory, Department of Physics, Lund University, 221 00 Lund, Sweden.|Hawai'i Institute of Geophysics and Planetology, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
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Schmitz
Department of Earth and Planetary Sciences, University of California at Davis, Davis, California 95616, USA.
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Yin
Department of Earth and Planetary Sciences, University of California at Davis, Davis, California 95616, USA.
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Sanborn
Astrogeobiology Laboratory, Department of Physics, Lund University, 221 00 Lund, Sweden.
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Tassinari
Hawai'i Institute of Geophysics and Planetology, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
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Caplan
Hawai'i Institute of Geophysics and Planetology, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
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