Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-18T18:56:05.619Z Has data issue: false hasContentIssue false
  • English
  • Français

The origin of three garnet isograds in Adirondack gneisses

Published online by Cambridge University Press:  14 March 2018

A. F. Buddington
A. F. Buddington*
Affiliation:
Geology Dept., Princeton University, Princeton, New Jersey, U.S.A.
Get access Rights & Permissions [Opens in a new window]

Summary

Three isograds may be drawn, indicating increasing grades of metamorphism in the northern Adirondack area, based on the development of garnet successively in biotite-quartz-plagioclase paragneiss, metadolerite and metagabbro gneiss, and in syenite and quartz syenite orthogneisses. Changes in the accompanying minerals show that this is an order of increasing temperature. Rocks of similar chemical composition, suitable for the development of garnet, occur in each grade of metamorphism and geologic studies indicate adequate temperature and depth for the development of garnet even where it is not present. The degree of development of garnet in rocks of similar chemical composition, in even as high a grade as the pyroxene-granulite subfacies, is widely variable. All of the data are consistent with an hypothesis that the successive development of a garnetiferous facies for each of the different kinds of gneisses mentioned required special conditions that facilitated the kinetics of the reaction, such as temperature in excess of that for equilibria, in order for the garnet reaction to proceed. The data are not conclusive as to whether certain non-garnetiferous facies of amphibolites are due to the physical conditions (such as high partial pressure of H2O for the prevailing temperature and load pressure) or to non-equilibria.

Type
Research Article
Information
Mineralogical magazine and journal of the Mineralogical Society , Volume 34 , Issue 268 , 1965 , pp. 71 - 81
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1965

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

Bartholomé, (P.), 1956. Princeton Ph.D. thesis.Google Scholar
Bartholomé, (P.), 1960. Econ. Geol., vol. 55, p. 255.CrossRefGoogle Scholar
Buddington, (A.F.), 1939. Geol. Soc. Amer., Mem. 7.Google Scholar
Buddington, (A.F.), 1952. Amer. Jour. Sci., Bowen vol., p. 37.Google Scholar
Buddington, (A.F.), 1963. Bull. Geol. Soc. Amer., vol. 74, p. 1155.CrossRefGoogle Scholar
Engel, (A. E. J.) and Engel, (C.G.), 1958. Bull. Geol. Soc. Amer., vol. 69, p. 1369. Engel (A. E. J..CrossRefGoogle Scholar
Engel, (A. E. J.) 1960. Ibid., vol. 71, p. 1.Google Scholar
Engel, (A. E. J.) 1962. Geol. Soc. Amer., Buddington vol., p. 37.Google Scholar
Fermor, (L.L.), 1913. Records Geol. Survey India, vol. 43, pt. 1, p. 41.Google Scholar
Gjelsvik, (T.), 1952. Norsk Geol. Tidsskrifb, vol. 30, p. 33.Google Scholar
Miyashiro, (A.), 1958. Journ. Fac. of Sci., Univ. of Tokyo, Ser. IT, vol. ll , p. 219.Google Scholar
Shido, (F.) 1958. Ibid., p. 131.Google Scholar
Turner, (F.J.) and Verhoogen, (J.), 1960. Igneous and etamorphie Petrology, McGraw-Hill.Google Scholar
Wilcox, (R.E.) and Poldervaart, (A.), 1958.Bull. Geol. Soc. Amer vol. 69, p. 1323.CrossRefGoogle Scholar
Wiseman, (J. D. H.), 1934. Quart. Journ. Geol. Soc., vol. 90, p. 354.CrossRefGoogle Scholar
Yoder, (H.S.), 1952. Amer. Journ. Sci., Bowen vol., p. 569.Google Scholar