Albite oxygen isotope fractionation

Clayton RN, Goldsmith JR, Mayeda TK (1989) Oxygen isotope fractionation in quartz, albite, anorthite, and calcite. Geochim Cosmochim Acta 53 725-733... 

Cla5don R. N., Goldsmith J. R., and Mayeda T. K. (1989). Oxygen isotope fractionations in qnartz, albite, anorthite and calcite. Geochim. Cosmochim. Acta, 53 725-733. 

Matsuhisa, Y., Goldsmith, J.R., Clayton, R.N. 1979. Oxygen isotopic fractionation in the system quartz-albite-anothite-water. Geochimica et Cosmochimica Acta, 43, 1131-1140. 

Clayton RN, Goldsmith JR, Karel KJ, Mayeda TK, Newton RP (1975) Limits on the effect of pressure in isotopic fractionation. Geochim Cosmochim Acta 39 1197-1201 Clayton RN, Onuma N, Grossman C, Mayeda TK (1977) Distribution of the presolar component in Allende and other carbonaceous chondrites. Earth Planet Sd Lett 34 209-224 Clayton RN, Goldsmith JR, Mayeda TK (1989) Oxygen isotope fractionation in quartz, albite, anorthite and caldte. Geochim Cosmochim Acta 53 725-733 Cliff SS, Thiemens MH (1997) The 0/ 0 and 0/ 0 ratios in atmospheric nitrous oxide a mass independent anomaly. Science 278 1774-1776 Cliff SS, Brenninkmeijer CAM, Thiemens MH (1999) First measurement of the 0/ 0 and ratios in stratospheric nitrous oxide a mass-independent anomaly. J Geophys Res 104 16171-16175... 

Compositional effects in silicates. Compositional effects are also important in the oxygen isotope fractionation behavior of silicate minerals. The effects are complex, however, because of the large number of substitution mechanisms that operate in these minerals. Table 3 summarizes some of the major substitutions and their estimated effects on isotope fractionation (cf Kohn and Valley 1998a). Of the common substitution schemes, the plagioclase substitution has the largest isotopic effect. Experimental data (O Neil and Taylor 1967 Matsuhisa et al. 1979 Clayton et al. 1989) and theoretical calculations (Kieffer 1982) indicate a 1.05 to 1.2%o fractionation between albite and anorthite at 1000 K. This fractionation reflects the higher Si to Al ratio of albite, and the affinity of the Si-0 bond relative to the Al-0 bond for 0 (Taylor and Epstein 1962). In contrast to plagioclase, K Na substitution in the alkali feldspars, which does not affect the Si to Al ratio, has no measurable isotopic effect (Schwarcz 1966 O Neil and Taylor... 

Clayton RN, Goldsmith JR, Karel KJ, Mayeda TK, Newton RC (1975) Limits on the effect of pressure on isotopic fractionation. Geochim Cosmochim Acta 39 1197-1201 Clayton RN, Goldsmith JR, Mayeda TK (1989) Oxygen isotope fractionation in quartz, albite, anorthite, and calcite. Geochim Cosmochim Acta 53 725-733... 

Matsnhisa Y, Goldsmith JR, Clayton RN (1979) Oxygen isotopic fractionation in the system quartz-albite-anorthite-water. Geochim Cosmochim Acta 43 1131-1140 Matsno S, Friedman I, Smith GI (1972) Studies of Quaternary saline lakes. I. Hydrogen isotope fractionation in saline minerals. Geochim Cosmochim Acta 36 427-435 Mattey DP (1991) Carbon dioxide solubility and carbon isotope fractionation in basaltic melt. Geochim Cosmochim Acta 55 3467-3473... 

Figure 2. Experimentally determined oxygen isotope fractionations between calcite and quartz, albite, anorthite, diopside, forsterite and magnetite (Clayton and Kieffer 1991).

Matsuhisa Y., Goldsmith J.R. and Clayton R.N., 1979, Oxygen isotope fractionation in the systems quartz-albite-anorthite-water. Geochim. Cotmor/iini. Acta 43, 1131-1140. Matsui A., Onuma N., Nagasawa H, Hlguchi H. and Banno S., 1977, Crystal structure control in trace element partition between crystal and magma. BulL Sac. Fr. Mineral. 

The resulting temperature estimates in column (1) range from 613°C to 1126°C. Omitting the lowest and the highest values yields a mean of 872 112°C (let) The oxygen-isotope fractionation factors reported by Chiba et al. (1989) for feldspar-pyroxene are Albite-Diopside = 1.81, Anorthite-Diopside = 0.76. For labradorite (An = 60%, Ab = 40%) the numerical value of A is ... 

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