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Petrological Evidence for the Presence of Amphibole in the Upper Mantle and its Petrogenetic and Geophysical Implications

Published online by Cambridge University Press:  01 May 2009

E. R. Oxburgh
Affiliation:
Department of Geology and Mineralogy, University Museum, Oxford.

Abstract

In addition to meeting various geophysical requirements, an ultrabasic upper mantle must provide a source both for olivine nodules and for the range of “primary” basaltic types, i.e. those which are apparently uncontaminated and undifferentiated. Potassium abundances and other considerations suggest that olivine nodules represent upper mantle which has previously yielded basalt by partial fusion but is now “barren”, principally because of potassium depletion, and is unable to yield more. The possible range of potassium contents of “parent” upper mantle (still able to yield basalt) is considered and it is argued that at any concentration within this range, the potassium is not distributed between the main mantle phases as a trace component but is contained largely within a potassium-rich minor phase. It is shown that this phase is probably an amphibole and may make up between 2 and 20 wt. per cent of parent upper mantle. In addition to the isochemical phase changes to be expected with increasing depth, a transition is proposed from an upper zone of amphibole-free (barren) upper mantle to a lower zone of amphibole-bearing (parent) upper mantle. The petrogenetic and geophysical implications of such a model are discussed; in particular it provides a possible explanation for the Gutenberg low-velocity zone.

Type
Articles
Copyright
Copyright © Cambridge University Press 1964

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References

REFERENCES

Ahrens, L. H., Pinson, W. H., and Kearns, M. M., 1952. Association of rubidium and potassium and their abundance in common igneous rocks and meteorites. Geochim. et. cosmoch. Acta, 2, 229242.CrossRefGoogle Scholar
Alderman, A. R., 1936. Eclogites from the neighbourhood of Glenelg, Inverness-shire. Quart. J. geol. Soc. Lond., 92, 488530.CrossRefGoogle Scholar
Birch, F. 1951. Recent work on the radioactivity of potassium and some related geophysical problems. J. geophys. Res., 61, 107126.CrossRefGoogle Scholar
Birch, F. 1954. Heat from radioactivity; in Nuclear Geology, New York.Google Scholar
Birch, F. 1960. The velocity of compressional waves in rocks to 10 kilobars, Pt. 1. J. geophys. Res., 65, 10831102.CrossRefGoogle Scholar
Birch, F. 1961. The velocity of compressional waves in rocks to 10 kilobars, Pt. 2. J. geophys. Res., 66, 21992221.CrossRefGoogle Scholar
Bowen, N. L., 1928. The evolution of igneous rocks. Princeton.Google Scholar
Boyd, F. R., 1959. Hydrothermal investigations of amphiboles; in Researches in Geochemistry. New York.Google Scholar
Boyd, F. R., and England, J. L., 1960. Aluminous enstatite. Ann. Report of the Director of the Geophysical Laboratory. Yearb. Carneg. Instn. 59, 4952.Google Scholar
Boyd, F. R., and England, J. L., 1961. Melting of silicates at high pressures. Yearb. Carneg. Instn. 60, 113125.Google Scholar
Buddington, A. F., 1943. Some petrological concepts and the interior of the earth. Amer. Min., 28, 119140.Google Scholar
Bullard, E. C., 1954. The interior of the earth. The Earth as a Planet, II, 57137. Chicago.Google Scholar
Bullard, E. C., and Griggs, D. T., 1962. The nature of the Mohorovicic discontinuity. Geophys. J., 6, 118123.CrossRefGoogle Scholar
Bullen, K. E., 1953. An introduction to the theory of seismology. 2nd ed. Cambridge.Google Scholar
Deer, W. A., Howie, R. A., and Zussman, J., 1963. Rock forming minerals. Vol. II. London.Google Scholar
Dorman, J., Ewing, M., and Oliver, J. O., 1960. Study of shear wave distribution in the upper mantle by mantle Rayleigh waves. Bull. seismol. Soc. Amer., 50, 87116.Google Scholar
Ernst, W. G., 1960. The stability relations of magnesioriebeckite. Geochim. et cosmoch. Acta, 19, 1040.CrossRefGoogle Scholar
Ernst, W. G., 1962. Abstract. J. geophys. Res., 67, 3555.Google Scholar
Gutenberg, B., 1959(a). Physics of the Earth's Interior. New York.Google Scholar
Gutenberg, B., 1959(b). Wave velocities below the Mohorovicic discontinuity. Geophys. J., 2, 348352.CrossRefGoogle Scholar
Harris, P. G., 1957. Zone refining and the origin of potassic basalts. Geochim. et cosmoch. Acta, 12, 195208.CrossRefGoogle Scholar
Harris, P. G., and Rowell, J. A., 1960. Some geochemical aspects of the Mohorovicic discontinuity. J. geophys. Res., 65, 2443–59.CrossRefGoogle Scholar
Hess, H. H., 1955. The Oceanic Crust. J. Mar. Res., 14, 423439.Google Scholar
Hess, H. H., 1960. Stillwater igneous complex, Montana. Mem. geol. Soc. Amer., 80.Google Scholar
Holmes, A., 1927. Some problems of physical geology and the earth's thermal history. Geol. Mag., 64, 263278.CrossRefGoogle Scholar
Holyk, W., and Ahrens, L. H., 1953. Potassium in ultramafic rocks. Geochim. et cosmoch. Acta, 4, 241250.CrossRefGoogle Scholar
Kennedy, G. C., 1959. The origins of continents, mountain ranges, and oceanic basins. Amer. Scient., 47, 491504.Google Scholar
Kuno, H., 1959. Origin of Cenozoic petrographic provinces of Japan and surrounding areas. Bull. volcan. Serie II, 20, 3776.CrossRefGoogle Scholar
Kuno, H., 1960. High alumina basalt. J. Petrol., Oxford, 1, 121145.CrossRefGoogle Scholar
Kuno, H., Yamasaki, K., Iida, C., and Nagashima, K., 1957. Differentiation in Hawaiian magmas. Jap. J. Geol. Geogr., 28, 179218.Google Scholar
Lausen, C., 1927. The occurrence of olivine bombs near Globe, Arizona. Amer. J. Sci., 14, 293306.CrossRefGoogle Scholar
Lovering, J. F., 1958. The nature of the Mohorovicic discontinuity. Trans. Amer. geophys. Un., 39, 947955.Google Scholar
MacDonald, G. J. F., and Ness, N. F., 1961. A study of the free oscillations of the earth. J. geophys. Res., 66, 18651911.CrossRefGoogle Scholar
Nockolds, S. R., 1954. Average composition of some igneous rocks. Bull. geol. Soc. Amer., 65, 10071032.CrossRefGoogle Scholar
O'hara, M. J., 1961. Zoned ultrabasic and basic gneiss masses in the early Lewisian metamorphic complex at Scourie, Sutherland. J. Petrol., Oxford, 2, 248276.CrossRefGoogle Scholar
Powers, H. A., 1955. Composition and origin of basaltic magma of the Hawaiian islands. Geochim. et cosmoch. Acta, 7, 77107.CrossRefGoogle Scholar
Press, F., 1961. The Earth's crust and upper mantle. Science, 133, 14551463.CrossRefGoogle ScholarPubMed
Ringwood, A. E., 1958(a). The constitution of the earth's mantle—I. Geochim. et cosmoch. Acta, 13, 303321.CrossRefGoogle Scholar
Ringwood, A. E., 1958(b). The constitution of the earth's mantle—II. Geochim. et cosmoch. Acta, 15, 1829.CrossRefGoogle Scholar
Ringwood, A. E., 1958(c). The constitution of the earth's mantle—III. Geochim. et cosmoch. Acta, 15, 195212.CrossRefGoogle Scholar
Ringwood, A. E., 1962(a). A model for the upper mantle—I. J. geophys. Res., 67, 857868.CrossRefGoogle Scholar
Ringwood, A. E., 1962(b). A model for the upper mantle—II. J. geophys. Res., 67, 4473–78.CrossRefGoogle Scholar
Ross, C. S., Foster, M. D., and Myers, A. J., 1954. Origin of dunite and olivine rich inclusions in basaltic rocks. Amer. Min., 39, 693757.Google Scholar
Rubey, W. W., 1951. The geologic history of sea water. Bull. geol. Soc. Amer., 62, 11111147.CrossRefGoogle Scholar
Turner, F. J., and Verhoogen, J., 1960. Igneous and metamorphic petrology. 2nd Ed. New York.Google Scholar
Verhoogen, J., 1954. Petrological evidence on temperature distributions in the mantle of the earth. Trans. Amer. geophys. Un., 35, 8592.Google Scholar
Wager, L. R., 1958. Beneath the earth's crust. Advanc. Sci., Lond., 15, 3145.Google Scholar
Wagner, P. A., 1914. The diamond fields of Southern Africa. Johannesburg.Google Scholar
Watson, K. D., 1955. Kimberlite at Bachelor Lake, Quebec. Amer. Min., 60, 565579.Google Scholar
Wilshire, H. G., and Binns, R. A., 1961. Basic and ultrabasic xenoliths from the volcanic rocks of New South Wales. J. Petrol., Oxford, 2, 185208.CrossRefGoogle Scholar
Wyllie, P. J., 1960. The system CaO-MgO-FeO-SiO2 and its bearing on the origin of ultrabasic and basic rocks. Miner. Mag., 32, 459470.Google Scholar
Yoder, H. S., and Eugster, H. P., 1954. Phlogopite synthesis and stability range. Geochim. et cosmoch. Acta, 6, 157185.CrossRefGoogle Scholar
Yoder, H. S., and Tilley, C. E., 1962. Origin of basalt magmas—an experimental study of natural and synthetic rock systems. J. Petrol., Oxford, 3, 342532.CrossRefGoogle Scholar