Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-28T22:22:59.719Z Has data issue: false hasContentIssue false
  • English
  • Français

Petrology of the Anorthosite-Gabbro Mass at Kadavur, Madras, India1

Published online by Cambridge University Press:  01 May 2009

A. P. Subramaniam
A. P. Subramaniam
Affiliation:
Geological Survey of India, Southern Circle, Mylapore, Madras, 4, India.
Get access Rights & Permissions [Opens in a new window]

Abstract

A small body of anorthosite with related gabbroic facies from the Archaean of Southern India is described. The mass is inferred to be a funnel shaped phacolithic pluton, emplaced in the crest of a steeply plunging major anticline of metasedimentary quartzite and quartz schists. The marginal rocks of the mass are gabbroic and foliated, while the core is largely made of massive anortho-sites occasionally showing flow structures. The chemistry and petrography of the rocks of this mass suggest their having resulted from differentiation in place of a gabbroic anorthosite intrusion. This occurrence is thought to be a unique example of the Adirondack type of anorthosite, and supports Buddington's hypothesis of evolution of anorthositic rocks from a gabbroic anorthosite magma.

Type
Articles
Information
Geological Magazine , Volume 93 , Issue 4 , August 1956 , pp. 287 - 300
Copyright
Copyright © Cambridge University Press 1956

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

Published by permission of Director, Geological Survey of India.

References

REFERENCES

Balk, R., 1937. Structural Behaviour of Igneous Rocks. Mem. Geol. Soc. Amer., v.Google Scholar
Buddington, A. F., 1939. Adirondack Igneous Rocks and their Meta-morphism. Mem. Geol. Soc. Amer., vii.Google Scholar
Chatterjee, S. C., 1936. The Anorthasites of Bengal, University of Calcutta.Google Scholar
Fowler, K. S., 1930. The Anorthosite area of the Laramie Mountains, Wyoming, Parts 1 and 2, Amer. Journ. Sci., xix, 305–315, 373–403.CrossRefGoogle Scholar
Hess, H. H., 1952. Orthopyroxenes of the Bushveld type, ion substitutions and changes in unit cell dimensions. Amer. Journ. Sci., Bowen Volume, 174–187.Google Scholar
Johannsen, A., 1937. Petrography, Vol. 3, University of Chicago Press, 196–243.Google Scholar
Nockolds, S. R., 1954. Average compositions of some igneous rocks. Bull. Geol. Soc. Amer., lxv, 1007–1032.CrossRefGoogle Scholar
Poldervaart, A., 1950. Correlation of physical properties and chemical composition, in the plagioclase, olivine and orthopyroxene series, Amer. Miner., xxxv, 1067–1079.Google Scholar
Poldervaart, A., and Hess, H. H., 1951. Pyroxenes in the crystallization of basaltic magma. Journ. Geol., lix, 472–489.CrossRefGoogle Scholar
Vogt, T., 1927. Sulitelmafeltets geologi og petrografi (Geology and petrology of the Sulitelma district. English summary), Norg. Geol. Undersok, Nr. 121, 449–560.Google Scholar
Washington, H. S., 1917. Chemical analyses of igneous rocks. U.S. Geol. Surv., Prof. Paper, xcix, 302.Google Scholar
Winchell, A. N., 1945. Variation in composition and properties of calciferous amphiboles. Amer. Miner., xxx, 27–50.Google Scholar