Abstract
Polarized near-UV spectra have been recorded on 20 μm diameter spots on oriented crystals of microprobe-analyzed olivines from Baikhal Rift, Fa8.8 (I) and Seberget, Fa9.3 (II), which have formed under different fO2 and, therefore, are expected to contain Fe3+-bearing point defects in different concentrations. These should be reflected in the UV-spectra of such minerals (Cemic et al. 1986). The spectra obtained confirm these predictions: The difference in α Y, 26500 in both samples indicates a difference in Fe3+-site fractions of ΔXFe. = 1.78-10−4, which may be related to an fO2 about ten times higher for the formation of olivine II compared to I.
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Cemic L, Grammenopoulou-Bilal S, Langer K (1986) A microscope-spectrometric method for determining small Fe3 +-concentration due to Fe3 +-bearing defects in fayalite. Ber Bunsenges Phys Chem 90:654–661
Clocchiatti R, Hassare D, Yehanno C (1981) Origin hydrothermale des olivines gemmes de l'isle de Zabargad (St. Johns), Mer Rouge, par l'etude de leurs inclusions. Bull Min 104:354–360
Khisina NR (1987) Subsolidus transformation of solid solutions of rock forming minerals. Nauka, Moscow, p 237
Khisina NR, Meshalkin SS, Borisov AA, Urusov VS (1990) On the mechanism of changes in the intersite distribution coefficient of Fe and Mg in olivines under different T and fO2 conditions. Geokhimyia 8:1096–1106 (in Russian)
Langer K (1988) UV to NIR spectra of silicate minerals obtained by microscope spectrometry and their use in mineral thermodynamics and kinetics. In: Salje EKH (ed) Physical properties and thermodynamic behaviour of minerals. Reidel, Dordrecht, pp 639–685
Muravjova NI, Posdjakov RI, Kolesov GM, Tscherbina NA, Siomin VT (1989) Indication for mantle metasomatism in the Baikal Rift region. Geokhimyia 7:346–349
Nakamura A, Schmalzried H (1983) On the nonstoichiometry and point defects of olivine. Phys Chem Minerals 10:27–37
O'Neill HStC, Wall VJ (1987) The olivine-orthopyroxene-spinel oxygen geobarometer, the nickel precipitation curve, and the oxygen fugacity of the earth's upper mantle. J. Petrology 28:1169–1191
Nover G, Will G (1981) Structure refinement of seven natural olivne crystals and the influence of the oxygen partial pressure on cation distribution. Z Kristallogr 155:27–45
Ottonello G, Princivalle F, Della Giusta A (1990) Temperature, composition and fo2 effects on intersite distribution of Mg and Fe2+ in olivines. Phys Chem Minerals 17:301–312
Smith G, Langer K (1981) Polarized single-crystal near UV spectra of synthetic olivines. Naturwissenschaften 67:373
Smith G, Langer K (1982) High pressure spectra of olivines in the range 40000–11000 cm−1. In: Schreyer W (ed) High-pressure research in geosciences. Schweizerbart, Stuttgart, pp 259–268
Tossell JA, Vaughan DJ, Johnson KH (1974) The electronic structure of rutile, wustite, and hematite from molecular orbital calculations. Amer Mineral 59:319–334
Will G, Nover G (1979) Influence of oxygen partial pressure on the Mg/Fe distribution of Mg and Fe2+ in olivines. Phys Chem Minerals 17:199–208
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Khisina, N.R., Langer, K. & Partzsch, G. Effect of Fe3+-bearing point defects on the UV-spectra of two natural olivines. Phys Chem Minerals 18, 514–516 (1992). https://doi.org/10.1007/BF00205266
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DOI: https://doi.org/10.1007/BF00205266