2024-03-29T11:47:13Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/387512022-11-17T02:08:08Zhdl_2115_20039hdl_2115_116Discovery of 17,18 O-rich material from meteorite by direct-imaging method using stigmatic-SIMS and 2D ion detectorSakamoto, NaoyaItoh, ShoichiYurimoto, HisayoshiDirect-imagingStigmatic-SIMSIon detectorOxygen isotopeMeteoriteSolar System440We report a discovery of a chemically and isotopically unique material distributed ubiquitously in fine-grained matrix of a primitive carbonaceous chondrite Acfer 094. The observations were made in situ using a novel high precision imaging technique adopted direct-imaging method. The material is extremely enriched in heavy oxygen isotopes of O-17 and O-18 of +18% relative to the Earth's ocean while previously reported variation of oxygen isotopes is as large as a range from -8% to 0%. Based on the unique chemical composition of the material, the abundance of the material in the meteorite matrix is calculated to be 94 ± 20 (σ) ppm by volume using elemental mapping with a 7 μm2 spatial resolution by FE-SEM-EDS on the meteorite thin section. The average size of identified materials is 5 x 5 x 5 μm3. Therefore, isotope imaging capability over 500 x 500 μm2 area with micron resolution and an isotopic ratio precision of 1 percent is required to investigate about the presence of such material.Elsevier B.V.Journal Articleapplication/pdfhttp://hdl.handle.net/2115/38751https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/38751/1/255-4_p1458-1460.pdf0169-4332Applied Surface Science2554145814602008-12-15enginfo:doi/10.1016/j.apsusc.2008.05.052author