Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-30T15:45:15.739Z Has data issue: false hasContentIssue false
  • English
  • Français

The chemistry and cell parameters of omphacites and related pyroxenes

Published online by Cambridge University Press:  05 July 2018

A. D. Edgar ,
A. Mottana  and
N. D. Macrae
A. D. Edgar
Affiliation:
Department of Geology, University of Western Ontario, London, Canada
A. Mottana
Affiliation:
Department of Geology, University of Western Ontario, London, Canada
N. D. Macrae
Affiliation:
Department of Geology, University of Western Ontario, London, Canada
Get access Rights & Permissions [Opens in a new window]

Summary

In an attempt to correlate the chemical compositions and cell sizes of omphacites and related pyroxenes, the cell dimensions of fifty-five analysed pyroxenes have been determined, or taken from the literature. Twenty-two of the chemical analyses are new, nineteen of them being done by electron microprobe. Approximately two-thirds of the total number of analyses may be considered first class, the remainder are of doubtful or unknown quality. Cell parameters, determined by X-ray powder diffraction methods, have errors of 0·1 % for the majority of samples, although for some samples taken from the literature errors are unknown.

The majority of methods of recalculating omphacite analyses into their end-member molecules are unsuitable for correlation of cell constants with chemistry, mainly due to the impossibility of graphical representation of more than three end-member molecules, and to the non-stoichiometry of these molecules. Using a modification of Tröger's (1962) method of recalculating chloromelanite analyses the present analyses have been recalculated into the diopside-jadeite-acmite and diopside-jadeite-hedenbergite molecules and compared with their determined cell parameters. Because of the gradations in all parameters between these end-member molecules, determination of compositions based on the cell parameters (a, b, c, vol, or β) can only be made within wide limits. However, using a method of projection of compositions from the acmite and hedenbergite apices to the diopside-jadeite join the ratios of diopside to jadeite can be determined for most samples to within ±5 mol%. As there are the most important constituents of most omphacites, this method permits an approximate estimation of omphacite compositions. From a knowledge of the cell sizes of the omphacite a rough indication of the conditions of formation of its host rock may also be obtained.

Type
Research Article
Information
Mineralogical Magazine , Volume 37 , Issue 285 , March 1969 , pp. 61 - 74
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1969

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.)

References

Bearth, (P.), 1965. Schweiz. Min. Petr. Mitt. 45, 179.Google Scholar
Bell, (P. M.) and Davis, (B. T. C.), 1965. Carnegie Institution Year Book, 64, 120.Google Scholar
Bianchi, (A.) and Dal Piaz, (G. B.), 1963. Ann. Mus. Geol. Bologna, 31, 39.Google Scholar
Bloxam, (T. W.), 1959. Amer. Journ. Sci. 257, 95.CrossRefGoogle Scholar
Chesnokov, (B. V.) and PoPov, (V. A.) , 1965. Doklady Akad. Nauk S.S.S.R. (English translation), 162, 176.Google Scholar
Church, (W. R.), 1968a. In Basalts: The Poldervaart Treatise on Rocks of Basaltic Composition, eds. Hess, (H. H.), and Poldevaart, (A.).Google Scholar
Church, (W. R.), 1968b. Bull. Amer. Ass. Petrol. Geol. (in the press).Google Scholar
Clark, (J. R.) and Papike, (J. J.), 1968. Amer. Min. 53, 840.Google Scholar
Clark, (S. P.) Jr., Schairer, (J. F.), and de Neufville, (J.), 1962. Carnegie Institution Year Book, 62, 59.Google Scholar
Coleman, (R. G.), 1961. Journ. Petrology, 2, 209.CrossRefGoogle Scholar
Coleman, (R. G.), Lee, (D. E.), Beatty, (L. B.), and Brannock, (W. W.), 1965. Bull. Geol. Soc. America, 76, 483.CrossRefGoogle Scholar
Coleman, (R. G.) and Clark, (J. R.), 1968. Amer. Journ. Sci. 266, 43.CrossRefGoogle Scholar
Eskola, (P.), 1921. Vidensk. selskap, skr. Kristiania. L Matem. Naturvid. Klasse. 8, 1.Google Scholar
Essene, (E. J.) and Fyfe, (W. S.), 1967. Contr. Min. Petr. 15, 1.CrossRefGoogle Scholar
Foshag, (W. F.), 1955. Amer. Min. 40, 1062.Google Scholar
Frondel, (C.) and Klein, (C.) Jr., 1965. Science, 149, 742.CrossRefGoogle Scholar
Gilbert, (M. C.), 1966. Carnegie Institution Year Book, 65, 241.Google Scholar
Gilbert, (M. C.), 1967. Ibid. 66, 374.CrossRefGoogle Scholar
Ginzburg, (I. V.) and Sidorenko, (G. A.) , 1964. Geochemistry International (English translation), 1,536.Google Scholar
Hashimoto, (M.), 1964. Proc. Japan Acad. 40, 31.CrossRefGoogle Scholar
Hezner, (L.), 1903. Tschermaks Min. Petr. Mitt. 22, 437 and 505.Google Scholar
Huckenholz, (H. G.), 1965. Beitr. Min. Petr. 11, 415.CrossRefGoogle Scholar
Jackson, (E. D.), 1966. U.S. Geol. Survey Prof. Paper, 550 D, 151.Google Scholar
Kappel, (F.), 1967. Neues Jahrb. Min., Abh. 107, 266.Google Scholar
Kushiro, (L.), 1962. Japan Journ. Geol. Geogr. 33, 213.Google Scholar
Lacroix, (A.), 1917. Compt. Rend. Acad. Sci. Paris, 165, 381.Google Scholar
Lacroix, (A.), 1930. Bull. Soc. franç. Min. 53, 216.Google Scholar
Livingstone, (A.), 1967. Min. Mag. 36, 380.Google Scholar
McBirney, (A.), Aoki, (K.), and Bass, (M. N.), 1967. Amer. Min. 52, 908.Google Scholar
Miyashiro, (A.) and Seki, (Y.), 1958. Japan. Journ. Geol. Geogr. 29, p. 199.Google Scholar
Mottana, (A.), Church, (W. R.), and Edgar, (A. D.), 1968. Contr. Min. Petr. (in the press).Google Scholar
Mozzi, (R.) and Newell, (J.), 1961. Int. Union Cryst. 5.Google Scholar
Nicolas, (A.), 1966. D.Sc. Thesis, Nantes, 2 vols.Google Scholar
Peck, (L. C.), 1964. U.S. Geol. Surv. Bull. 1170, I.Google Scholar
Schmitt, (H. H.V.), 1963. Ph.D. Thesis, Harvard.Google Scholar
Seki, (Y.) and Onuki, (H.), 1967. Journ. Jap. Ass. Min. Petr. Econ. Geol. 58, 233.CrossRefGoogle Scholar
Shapiro, (L.) and Brannock, (W. W.), 1962. U.S. Geol. Surv. Bull. 1144 A, I.Google Scholar
Smuhkowski, (K.), 1964. Geologia Sudetica, 1, 13.Google Scholar
Smuhkowski, (K.), 1965. Bull. Acad. Polon. Sci., Ser. sci. geol. geogr. 13, II.Google Scholar
Spry, (A.), 1963. Min. Mag. 33, 589.Google Scholar
Switzer, (G.), 1945. Amer. Journ. Sci. 243, I.CrossRefGoogle Scholar
Tröger, (W. E.), 1951. Neues Jahrb. Min., Monatsh. 132.Google Scholar
Tröger, (W. E.), 1962. Tschermaks Min. Petr. Mitt., ser. 3, 8, 24.CrossRefGoogle Scholar
Velde, (B.), 1966. Bull. Soc. franc. Min. Crist. 89, 385.Google Scholar
Vogel, (D. E.), 1966. Neues Jahrb. Min. Monatsh. 185.Google Scholar
Vogel, (D. E.), 1967. Geol. en Mijnbow, 46, 411.Google Scholar
Warner, (J.), 1964. Amer. Min. 49, 1461.Google Scholar
White, (A. J. R.), 1964. Amer. Min. 49, 883.Google Scholar
Williams, (A. F.), 1932. The Genesis of the Diamonds, 2 vols., p. 629. Benn, London.Google Scholar
Wolfe, (C. W.), 1955. Amer. Min. 40, 248.Google Scholar
Yagi, (K.), 1958. Journ. Min. Soc. Japan, 3, 763.Google Scholar
Yoder, (H. S.) Jr., 1950. Amer. Journ. Sci. 248, 225 and 312.CrossRefGoogle Scholar
Yoder, (H. S.) Jr. and Tilley, (C. E.), 1962. Journ. Petrology, 3, 342.CrossRefGoogle Scholar

A correction has been issued for this article:

Errata