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Oscillatory zoned chrome lawsonite in the Tavşanlı Zone, northwest Turkey

Published online by Cambridge University Press:  05 July 2018

S. C. Sherlock  and
A. I. Okay
S. C. Sherlock*
Affiliation:
Department of Earth Sciences, The Open University, Milton Keynes, UK
A. I. Okay
Affiliation:
ITÜ, Maden Fakiiltesi, Jeoloji Bölümü, Ayazaga 80624, Istanbul, Turkey
*
* Corresponding author
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Abstract

Blueschist-facies metabasite rocks from the Tavşanlı Zone of northwest Turkey have been found to contain an abundance of lawsonite displaying oscillatory zoning. Lawsonite normally adheres to the ideal composition of CaAl2[Si2O7](OH)2.H2O. In two samples from the Tavşanlı Zone, Al3+-Cr3+ substitution has occurred. The Cr3+ was probably present in the protolith as magmatic chromite, became incorporated into lawsonite during subduction, and is a metamorphic feature resulting from quantities of Cr in the protolith and local fluid conditions.

Keywords

lawsoniteoscillatory zoningmetamorphic rocksTavşanlı zoneTurkey
Type
Research Article
Information
Mineralogical Magazine , Volume 63 , Issue 5 , October 1999 , pp. 687 - 692
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1999

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Footnotes

†

Present address: Geological Survey of Norway, Leiv Eirikssons vei 39, 7491-Trondheim, Norway

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