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Myrmekite from the Charnockitic Rocks of the Eastern Ghats, India

Published online by Cambridge University Press:  01 May 2009

C. Bhattacharyya
C. Bhattacharyya
Affiliation:
Department of Geology, Presidency CollegeCalcutta 12, India
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Summary

The myrmekite occurring in acid to basic charnockites of the area around Garbham and Shikaruganji, Srikakulam district, Andhra Pradesh is described. Myrmekite, whenever present, occurs only at the contact of plagioclase and potash feldspar. The textures and paragenesis of minerals suggest that potash feldspar reacted with plagioclase giving rise to myrmekite under favourable stress condition, higher stress favouring the formation of myrmekite. The difference in the stress factor or the microstrain pattern in the rock can explain the presence of myrmekite at some contacts of plagioclase–potash feldspar and absence in others.

Type
Articles
Information
Geological Magazine , Volume 108 , Issue 5 , September 1971 , pp. 433 - 438
Copyright
Copyright © Cambridge University Press 1971

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