L‐chondrite asteroid breakup tied to Ordovician meteorite shower by multiple isochron 40Ar‐39 Ar dating

  title={L‐chondrite asteroid breakup tied to Ordovician meteorite shower by multiple isochron 40Ar‐39 Ar dating},
  author={Ekaterina V. Korochantseva and Mario Trieloff and Cyril A. Lorenz and Alexey I. Buykin and Marina A. Ivanova and Winfried H. Schwarz and Jens Hopp and Elmar K. Jessberger},
  journal={Meteoritics \& Planetary Science},
Abstract— Radiochronometry of L chondritic meteorites yields a rough age estimate for a major collision in the asteroid belt about 500 Myr ago. Fossil meteorites from Sweden indicate a highly increased influx of extraterrestrial matter in the Middle Ordovician ∼480 Myr ago. An association with the L‐chondrite parent body event was suggested, but a definite link is precluded by the lack of more precise radiometric ages. Suggested ages range between 450 ± 30 Myr and 520 ± 60 Myr, and can neither… 

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