40Ar-39Ar analyses of Yamato-75097 (L6) chondrite from Antarctica

• Main Authors: Kaneoka, Ichiro, Takaoka, Nobuo, Yanai, Keizo
• Language: English
• Published: National Institute of Polar Research 1988
• Subjects: Yamato; Antarc*; Antarctica
• Online Access: https://nipr.repo.nii.ac.jp/record/4457/files/KJ00000036263.pdf; https://doi.org/10.15094/00004457; https://nipr.repo.nii.ac.jp/records/4457

P(論文) ^<40>Ar-^<39>Ar analyses were performed on the host phase of an H-clast bearing chondrite Yamato-75097 (L6). The result indicates a typical U-shaped age spectrum, suggesting that the serious degassing event occurred at about 490Ma or slightly younger age for this meteorite. Since the meteorite shows a sign of shock, this event might have been a collisional event. It is estimated that more than 99% of radiogenic ^<40>Ar was degassed during this event. For this degassing, it requires prolonged time of at least a few hours even at 1200℃, and a longer time is required if the ambient temperature is lower and the diffusion mainly controls the degassing process. departmental bulletin paper