Thermoluminescence studies of ordinary chondrites in the Japanese Antarctic meteorite collection, II: New measurements for thirty type 3 ordinary chondrites

• Main Authors: Kiyotaka Ninagawa, Konosuke Soyama, Masanori Ota, Shin Toyoda, Naoya Imae, Hideyasu Kojima, Paul H. Benoit, Derek W.G. Sears
• Format: Report
• Language: English
• Published: Department of Applied Physics, Okayama University of Science/Department of Applied Physics, Okayama University of Science/Department of Applied Physics, Okayama University of Science/Department of Applied Physics, Okayama University of Science/National Institute of Polar Research/National Institute of Polar Research/Cosmochemistry Group, Department of Chemistry and Biochemistry, University of Arkansas/Cosmochemistry Group, Department of Chemistry and Biochemistry, University of Arkansas 2000
• Subjects: Antarctic; Yamato; Antarc*
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=5972; http://id.nii.ac.jp/1291/00005972/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=5972&item_no=1&attribute_id=18&file_no=1

We have measured the thermoluminescence (TL) properties of thirty type 3 ordinary chondrites from the Japanese Antarctic meteorite collection. This brings to 73 the total number of Japanese type 3 ordinary chondrites examined in this way by the Arkansas-Okayama collaboration. Fifteen pairing groups were found using TL and geographical criteria. Most of the new meteorites are of petrologic types 3.6-3.9,but fourteen are of petrologic type ≤3.4. Six of the 73 meteorites (Yamato (Y)-790448,Y-793596,Y-793565,Y-791324,Y-791558,Y-74660) have petrographic types <3.2,and are therefore particularly valuable samples of primitive solar system material. Most of the meteorites with high TL sensitivity (petrologic type >3.5) tend to have higher induced TL peak temperature and peak width than those with low TL sensitivity, in confirmation of earlier work and consistent with peak temperature and width as well as TL sensitivity, being independent parameters of thermal history. Samples not obeying these trends (Y-75029,Y-86706,Y-793567 and Y-790787), are either heavily weathered or experienced atypical thermal histories.