X-ray Rietveld and 57Fe Mössbauer study of babingtonite from Kouragahana, Shimane Peninsula, Japan
スポンサーリンク
概要
- 論文の詳細を見る
Babingtonite from Kouragahana, Shimane Peninsula, Japan, was investigated using electron microprobe, X-ray Rietveld, and 57Fe Mössbauer spectral analyses to characterize its chemical compositions, crystal structure, oxidation state of Fe, and distribution of Fe between two crystallographically independent octahedral Fe1 and Fe2 sites. The Kouragahana babingtonite occurs as single parallelohedrons with {100}, {001}, {001}, {111}, {110}, and {101} and sometimes shows penetration twinning. Both normal and sector-zoned crystals occur. Babingtonite crystals with sector zoning consist of sectors relatively enriched in Fe and of sectors enriched in Mg, Mn, and Al. Babingtonite also shows compositional zoning with higher Fe2+ and Al core and higher Fe3+ and Mn rim. The average Fe content of the babingtonite without sector zoning is similar to the Fe2+-rich sector of the sector-zoned babingtonite. The chemical formula based on the average composition of all analytical data (n = 193) is [Na0.01(2)Ca2.01(2)] [Mg0.11(4)Mn0.09(3)Fe2+0.76(7)Fe3+0.93(5)Ti0.01(1)Al0.06(5)]Si5.01(4)O14(OH). X-ray Rietveld refinement was carried out using a model of space group P1. The result of the refinement is characterized by R-weighted pattern = 9.91, R-expected pattern = 6.37, and goodness-of-fit = 1.56. The unit cell parameters are a = 7.4667(3), b = 11.6253 (6), c = 6.6820(2) Å, α = 91.533(4), β = 93.886(3), γ = 104.203(4)°, and V = 560.43(4) Å3. The refined site occupancies of atoms in the Fe1 and Fe2 sites are [Fe0.91(2)Mg0.09] and [Fe0.91(2)Al0.09], respectively, if Mg is assumed to distribute in the Fe1 site and Al in the Fe2 site. By allocating Mn, 0.09 atoms per formula unit (a.p.f.u.), to the Fe1 site, the site populations in the Fe1 and Fe2 sites are determined as [Fe0.82(2)Mn0.09Mg0.09] and [Fe0.91(2)Al0.09] a.p.f.u., respectively. The 57Fe Mössbauer spectrum taken at room temperature consists of three peaks, which were resolved into two doublets assigned to Fe2+ and Fe3+ at the two octahedral sites. The Fe2+:Fe3+ ratio was determined as Fe2+:Fe3+ = 43.3(3):56.7(4) and 47.1(4):52.9(3) by applying two fitting models, and the average Fe2+:Fe3+ ratio was 45.2(4):54.8(4). The results of X-ray Rietveld analysis and Mössbauer spectroscopy indicate that Fe2+ and Fe3+ are ordered at the Fe1 and Fe2 sites, respectively, in the Kouragahana babingtonite.
著者
-
Akasaka Masahide
Department Of Geoscience Faculty Of Science And Engineering Shimane University
-
Kimura Takehiko
Department Of Medicine And Bioregulatory Sciences Graduate School Of Medical Sciences University Of
-
Nagashima Mariko
Department Of Earth Science Graduate School Of Science And Engineering Yamaguchi University
関連論文
- Crystal chemistry of Mn^-, Sr-rich and REE-bearing piemontite from the Kamisugai mine in the Sambagawa metamorphic belt, Shikoku, Japan
- X-ray single-crystal and optical spectroscopic study of chromian pumpellyite from Sarany, Urals, Russia
- P-62 The Role of Clinical Psychologist Working in the Obstetrics and Gynecology : Based on the Experience of 12 Years(ISPOG2007)
- Menopausal insomnia and hormone replacement therapy
- Silver-Bearing and Associated Minerals in El Zancudo Deposit, Antioquia, Colombia
- Distribution of chromium among the octahedral sites in chromian epidote from Iratsu, central Shikoku, Japan
- Area analysis of chondrules in the Allende meteorite by electron microprobe
- Chromian pumpellyite and associated chromian minerals from Sangun metamorphic rocks, Osayama, southwest Japan
- ^Fe Mossbauer and X-ray Rietveld studies of ferrian prehnite from Kouragahana, Shimane Peninsula, Japan
- Distribution of Fe^ in a synthetic (Ca, Na)_2 (Mg, Fe^) Si_2O_7-melilite : ^Fe Mossbauer and X-ray Rietveld studies
- Hydrothermal syntheses of epidote and piemontites on the join Ca_2Al_2Fe^Si_3O_(OH)-Ca_2Al_2Mn^Si_3O_(OH) at relatively low pressures of 200-400MPa
- Chromian epidote in omphacite rocks from the Sambagawa metamorphic belt, central Shikoku, Japan
- Ore minerals and mineralization stages of Chaarat gold-bearing antimony deposit, Middle Tien-Shan, Kyrgyzstan
- Oxidation state of Fe in olivine in a lherzolite xenolith from Oku district, Oki-Dogo Island, Shimane Prefecture, Japan
- Mineralization Sequence of Gatsuurt Gold deposit in North Khentei gold belt, Central Northern Mongolia
- Crystal chemistry of Mn2+-, Sr-rich and REE-bearing piemontite from the Kamisugai mine in the Sambagawa metamorphic belt, Shikoku, Japan
- Tanohataite, LiMn_2Si_3O_8(OH) : a new mineral from the Tanohata mine, Iwate Prefecture, Japan
- Petrology, Geochemistry, and Fluid Inclusion Microthermometry of Sphalerite from the Laloki and Federal Flag Strata-Bound Massive Sulfide Deposits, Papua New Guinea : Implications for Gold Mineralization
- Ag-rich Tetrahedrite in the El Zancudo Deposit, Colombia : Occurrence, Chemical Compositions and Genetic Temperatures
- Gold Mineralization and Genesis of Gatsuurt deposit in North Khentei gold belt, Central Northern Mongolia
- Oxidation state of Fe in olivine in andesitic scoria from Kasayama volcano, Hagi, Yamaguchi Prefecture, Japan
- The Crater Mountain Deposit, Papua New Guinea : Porphyry-related Au-Te System
- X-ray Rietveld and 57Fe Mössbauer study of babingtonite from Kouragahana, Shimane Peninsula, Japan
- Oxidation states of Fe and precipitates within olivine from orthopyroxene-olivine-clinopyroxene andesite lava from Kasayama volcano, Hagi, Yamaguchi, Japan
- Oxidation states of Fe and precipitates within olivine from orthopyroxene-olivine-clinopyroxene andesite lava from Kasayama volcano, Hagi, Yamaguchi, Japan