An ⁵⁷Fe Mössbauer study of the ordinary chondrite meteorite Lynch 001

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• 作者：Nancy N. Elewa ; J. M. Cadogan
• 关键词：Mössbauer spectroscopy ; Terrestrial age ; Meteorites
• 刊名：Hyperfine Interactions
• 出版年：2017
• 出版时间：November 2017
• 年：2017
• 卷：238
• 期：1
• 全文大小：
• 刊物类别：Physics and Astronomy
• 刊物主题：Nuclear Physics, Heavy Ions, Hadrons; Atomic, Molecular, Optical and Plasma Physics; Condensed Matter Physics; Surfaces and Interfaces, Thin Films;
• 出版者：Springer International Publishing
• ISSN：1572-9540
• 卷排序：238

文摘

The Lynch 001 meteorite was found in the Nullarbor Plain region of Western Australia in 1977. This meteorite is classified as an ordinary chondrite of the petrologic group L5/6 that has undergone ‘minor to moderate’ terrestrial weathering. Here, we characterize the Fe-bearing phases in this chondrite using 57Fe Mössbauer spectroscopy carried out over the temperature range 13 K to room temperature (295 K). The paramagnetic doublets of olivine, pyroxene and a superparamagnetic ferric phase dominate the room temperature Mössbauer spectrum. On the basis of the room temperature quadrupole splitting of the olivine component, we estimate its composition to be Fa ₃₀₍₅₎. Besides the paramagnetic ferric component, accounting for ∼15 % of the spectral area at room temperature, magnetically ordered ferric phases were also detected. The total relative proportion of the Fe 3+ components allows us to estimate the terrestrial age of Lynch 001 to be 6,500 ± 1,500 yr, consistent with the value of 6,700 ± 1,300 yr determined by 14C dating.