Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-19T03:01:32.606Z Has data issue: false hasContentIssue false

Oxygen isotope fractionation between rutile and water and geothermometry of metamorphic eclogites

Published online by Cambridge University Press:  05 July 2018

Alan Matthews
Affiliation:
Department of Geology, Hebrew University of Jerusalem, JerusalemIsrael
Robert D. Beckinsale
Affiliation:
Geochemical Division, Institute of Geological Sciences, Gray's Inn Road, London WCIX 8NG
John J. Durham
Affiliation:
Geochemical Division, Institute of Geological Sciences, Gray's Inn Road, London WCIX 8NG

Summary

Oxygen isotope fractionation between rutile and water has been studied from 300 °C to 700 °C, PH2O = 1 kb, using aqueous oxidation of titanium metal as the equilibration reaction. The mechanism of rutile formation (which is critical to the assessment of isotopic equilibrium) is an ‘armouring’ reaction in which rutile grows around grains of titanium metal by solution-precipitation processes. Mean fractionation factors expressed as 103 In αTiO2-H2O obtained in the present study are:

−6.20±0.23‰ at 304±5 °C

−6.64±0.27‰ at 405±6 °C

−6.11±0.16%. at 508±6 °C

−4.45±0.28%. at 608±6 °C

−3.38±0.15%. at 698±6 °C.

These data agree with those obtained at temperatures above 500 °C by Addy and Garlick (1974) but do not accord with theoretical predictions by Bottinga and Javoy (1973). A minimum in the calibration curve 103 ln α versus 106T−2 occurs between 300 °C and 500 °C but from 500 °C to 700 °C 18O fractionation between rutile and water may be expressed by the equation:

103 ln α = −(4.72±0.40)106T−2+(1.62±0.53).

Oxygen isotope analyses of rutile and quartz from metamorphic eclogites and schists from the Tauern Window, Austria, yield isotopic temperatures at about 550 °C in agreement with results obtained on similar rocks from the Sesia Zone (Western Alps, Italy) and elsewhere by other workers. Petrologic studies indicate that the latest metamorphism of the Tauern eclogites reached about 450 °C Thus the measured partitions of 18O between rutile and quartz indicating temperatures around 550 °C have been inherited from an earlier metamorphic event.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1979

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

1

Present address: Department of Geophysical Sciences, University of Chicago.

References

Addy, (S. K.) and Garlick, (G. D.), 1974. Oxygen isotope fractionation between rutile and water. Contr. Mineral. Petrol. 45, 119-21.CrossRefGoogle Scholar
Becker, (R. H.) and Clayton, (R. N.), 1976. Oxygen isotope study of a Precambrian banded iron-formation, Hamersly Range, Western Australia. Geochim. Cosmochim. Act, 40, 1153-63.CrossRefGoogle Scholar
Beckinsale, (R. D.), Freeman, (N. J.), Jackson, (M. C.), Powell, (R. E.), and Young, (W. A. P.), 1973. A 30 cm radius 90° sector double collecting mass spectrometer with a capacitor integrating detector for high precision isotopic analyses of carbon dioxide. Int. J. Mass Spectrom. Ion Physics. 12, 299-308.CrossRefGoogle Scholar
Bottinga, (Y.) and Javoy, (M.), 1973. Comments on oxygen isotopic geothermometry. Earth Planet. Sci. Lett. 20, 250 65.CrossRefGoogle Scholar
Bottinga, (Y.) and Javoy, (M.) 1975. Oxygen isotope partitioning among the minerals in igneous and metamorphic rocks. Rev. Geophys. 13, 401-18.Google Scholar
Boyer, (P. D.), Graves, (D. J.), Suelter, (G. J.), and Dempsey, (M. E.), 1961. Simple procedure for the conversion of oxygen of orthophosphate or water to carbon dioxide for oxygen-18 determination. Anal. Chem. 33, 1906-9.CrossRefGoogle Scholar
Clayton, (R. N.) and Mayeda, (T. K.), 1963. The use of bromine pentafluoride in the extraction of oxygen from oxides and silicates for isotopic analysis. Geochim. Cosmochim. Acta. 27, 43-52.CrossRefGoogle Scholar
Clayton, (R. N.) O'Neil, (J. R.), and Mayeda, (T. K.), 1972. Oxygen isotope exchange between quartz and water. J. Geophys. Res. 77, 3057-67.Google Scholar
Coleman, (R. G.), Lee, (D. E.), Beatty, (L. B.), and Brennock, (W. W.), 1965. Eclogites and eclogites: their differences and similarities. Geol. Soc. Am. Bull. 76, 483-508.CrossRefGoogle Scholar
Desmons, (J.) and O'Neil, (J. R.), 1978. Oxygen and hydrogen isotope compositions of eclogites and associated rocks from the eastern Sesia zone (Western Alps, Italy. Contr. Mineral. Petrol. 67, 79-85.CrossRefGoogle Scholar
Epstein, (S.) and Mayeda, (T. K.), 1953. The variations in O18 content of water from natural sources. Geochim. Cosmochim. Acta. 4, 213-24.CrossRefGoogle Scholar
Frey, (M.), Hunziker, (J. C.), O'Neil, (J. R.), and Schwander, (H. W.), 1976. Equilibrium-Disequilibrium relations in the Monte Rosa Granite, Western Alps: Petrological, Rb-Sr and Stable Isotope Data. Contrib. Mineral. Petrol. 55, 147-79.CrossRefGoogle Scholar
Katiyar, (R. S.) and Krishnan, (R. S.), 1967. The vibrational spectrum of rutile. Phys. Lett. A. 25, 525-6.CrossRefGoogle Scholar
Kawabe, (I.), 1978. Calculation of oxygen isotope fractionation in quartz-water system with special reference to the low temperature fractionation. Geochim. Cosmochim. Acta. 42, 613-21.CrossRefGoogle Scholar
Lees, (D. G.), Calvert, (J. M.), and Derry, (D. J.), 1971. A technique using resonance capture of protons to study oxygen diffusion in titanium dioxide. In Sherwood, (J. N.), Chadwick, (A.V.), Muir, (W. M.), and Swinton, (F. L.) (eds.), Diffusion Processes. Gordon and Breach, London, 429-36.Google Scholar
Martin, (B.) and Fyfe, (W. S.), 1970. Some experimental and theoretical observations on the kinetics of hydration reactions with particular reference to serpentinization. Chem. Geol. 6, 185-202.CrossRefGoogle Scholar
Matsuhisa, (Y.), Goldsmith, (J. R.), and Clayton, (R. N.), 1978. Mechanisms of hydrothermal crystallisation of quartz at 250°C and 15 kilobars. Geochim. Cosmochim. Acta, 42, in press.CrossRefGoogle Scholar
Matthews, (A.), 1976a. Magnetite formation by the reduction of hematite with iron under hydrothermal conditions. Am. Mineral. 61, 927-32.Google Scholar
Matthews, (A.) 1976b. The crystallisation of anatase and rutile from amorphous titanium dioxide under hydrothermal conditions. Ibid. 419-32.Google Scholar
Matthews, (A.) and Beckinsale, (R. D.), 1979. Oxygen isotope equilibration systematics between quartz and water. Ibid. 64, 232-40.Google Scholar
Miller, (C.), 1974. On the metamorphism of the eclogites and high-grade blueschists from the Penninic Terrane of the Tauern Window, Austria. Schweiz. Mineral. Petrogr. Mitt., Band 54, 2/3, 371-84.Google Scholar
O'Neil, (J. R.), 1977. Stable Isotopes in Mineralogy. Phys. Chem. Minerals. 2, 105-23.CrossRefGoogle Scholar
O'Neil, (J. R.) and Taylor, Jr.(H. P.), 1967. The oxygen isotope and cation exchange chemistry of feldspars. Am. Mineral. 52, 1414-37.Google Scholar
O'Neil, (J. R.) and Taylor, Jr.(H. P.) 1969. Oxygen isotope equilibrium between muscovite and water. J. Geophys. Res. 74, 6012-22.CrossRefGoogle Scholar
O'Neil, (J. R.) and Taylor, Jr.(H. P.) Clayton, (R. N.), and Mayeda, (T. K.), 1969. Oxygen isotope fractionation in divalent metal carbonates. J. Chem. Phys. 51, 5547-58.CrossRefGoogle Scholar
O'Neil, (J. R.) Adami, (L. H.), and Epstein, (S.), 1975. Revised value of the O18 fractionation between CO2 and water at 25°C J. Res. US Geol. Surv. 3, 623-4.Google Scholar
Onuma, (N.), Clayton, (R. N.), and Mayeda, (T. K.), 1972. Oxygen isotope cosmothermometer. Geochim. Cosmochim. Acta. 36, 169-88.CrossRefGoogle Scholar
Stern, (M. J.), Spindel, (W.), and Monse, (E. U.), 1968. Temperature dependence of Isotope Effects. J. Chem. Phys. 48, 2908-19.CrossRefGoogle Scholar
Truesdell, (A. H.), 1974. Oxygen isotope activities and concentrations in aqueous salt solutions at elevated temperatures—consequences for isotope geochemistry. Earth Planet Sci. Lett. 23, 387-96.CrossRefGoogle Scholar
Vogel, (E. D.) and Garlick, (G. D.), 1970. Oxygen isotope ratios in metamorphic eclogites. Contrib. Mineral. Petrol. 28, 183 91.CrossRefGoogle Scholar
Williamson, (J. H.), 1968. Least Squares Fitting of a Straight Line. Canad. J. Phys. 46, 1845-7.CrossRefGoogle Scholar