Compositional Variation in Pyrochlores of Amba Dongar Carbonatite Complex, Gujarat

Authors

  • Shrinivas G. Viladkar
     Carbonatite Research Centre, Amba Dongar, Kadipani, Dist. Baroda - 390 117
  • Ulrich Bismayer
     Mineralogisch-Petrographisches Institut, Universitaet Hamburg, Grindelallee 48, 20146 Hamburg

Keywords:

Pyrochlore, Carbonatite, Zoning, Sovite, Amba Dongar, Gujarat.

Abstract

Pyrochlore is interpreted as a primary magmatic mineral that appeared in early carbonatite phases at Amba Dongar. Later intrusive phases incorporated this early pyrochlore and caused compositional modification, particularly around the rims, in response to changing magma chemistry. Consequently pyrochlore compositions show wide ranges in Nb, Ta, Ca, Ba, Ti and Ce. The final carbonatite phase was ankeritic and rich in hydrothermal fluids, giving rise to extreme compositional zoning and introduction of diverse elements (Si, U, Sr, Th, Fe), in the contained pyrochlore. Enrichment in radioelements such as U lead to metamictization, alteration and A-site vacancy.

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Issue

Volume 75, Issue 3, March 2010

Section

Research Articles

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Published

2010-03-01

How to Cite

Viladkar, S. G., & Bismayer, U. (2010). Compositional Variation in Pyrochlores of Amba Dongar Carbonatite Complex, Gujarat. Journal of Geological Society of India, 75(3), 495–502. Retrieved from https://www.geosocindia.com/index.php/jgsi/article/view/58360

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