General characterization of Antarctic micrometeorites collected by the 39th Japanese Antarctic Research Expedition: Consortium studies of JARE AMMs (III)

• Main Authors: Kentaro Terada, Toru Yada, Hideyasu Kojima, Takaaki Noguchi, Tomoki Nakamura, Toshio Murakami, Hajime Yano, Wataru Nozaki, Yoshihiro Nakamuta, Noriko Matsumoto, Junya Kamata, Takeshi Mori, Izumi Nakai, Miho Sasaki, Masato Itabashi, Takehito Setoyanagi, Keisuke Nagao, Takahito Osawa, Hajime Hiyagon, Sadahiro Mizutani, Takaaki Fukuoka, Ken-ichi Nogami, Rie Ohmori, Hideo Ohashi
• Format: Report
• Language: English
• Published: Department of Earth and Planetary Sciences, Hiroshima University/Department of Earth and Planetary Science, Faculty of Science, Kyushu University/National Institute of Polar Research/Department of Materials and Biological Sciences, Ibaraki University/Department of Earth and Planetary Science, Faculty of Science, Kyushu University/Computer Center, Gakushuin University/Planetary Science Division, The Institute of Space and Astronautical Science/Department of Earth and Planetary Science, Faculty of Science, Kyushu University/The Kyushu University Museum, Kyushu University/Department of Materials and Biological Sciences, Ibaraki University/Department of Materials and Biological Sciences, Ibaraki University/Department of Earth and Planetary Sciences, Hiroshima University/Department of Applied Chemistry, Science University of Tokyo/Department of Applied Chemistry, Science University of Tokyo/Department of Applied Chemistry, Science University of Tokyo/Department of Applied Chemistry, Science University of Tokyo/Laboratory for Earthquake Chemistry, The University of Tokyo/Laboratory for Earthquake Chemistry, The University of Tokyo/Department of Earth and Planetary Sciences, The University of Tokyo/Laboratory for Earthquake Chemistry, The University of Tokyo/Department of Environmental Systems, Rissho University/Department of Physics, Dokkyo University School of Medicine/Department of Physics, Dokkyo University School of Medicine/Department of Ocean Sciences, Tokyo University of Fisheries 2001
• Subjects: Antarctic; Yamato; Antarc*; Antarctica
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=6000; http://id.nii.ac.jp/1291/00006000/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=6000&item_no=1&attribute_id=18&file_no=1

From November 1998 to January 1999,the 39th Japanese Antarctic Research Expedition (JARE-39) undertook Japanese first large-scale collection of Antarctic micrometeorites (AMMs), with sizes larger than 10μm, at the Meteorite Ice Field around the Yamato Mountains in Antarctica (at three different locations, for a total of 24 collection sites). The number of collected AMMs larger than 40μm is estimated to be about 5000. Here we present the general characterization (i.e., micro-morphology and surface chemical composition using SEM/EDS) of ∿810 AMMs chosen from 5 of the 24 sites. Additionally, the mineral composition of 61 out of 810 AMMs was determined by Synchrotron X-ray radiation. Preliminary results on mineralogical and chemical compositions show similarities with that of previous studies, even though a pronounced alteration of some AMMs is noticed. A correlation is found between the Mg/Si ratio at the sample's surfaces of unmelted AMMs and the age of snow/ice in which the AMMs are embedded.