Baghban, S and Hosseinzadeh, MR and Moayyed, M and Mokhtari, MAA and Gregory, DD and Mahmoudi Nia, H, Chemical composition and evolution of the garnets in the Astamal Fe-LREE distal skarn deposit, Qara-Dagh-Sabalan metallogenic belt, Lesser Caucasus, NW Iran, Ore Geology Reviews, 78 pp. 166-175. ISSN 0169-1368 (2016) [Refereed Article]
Copyright 2016 Elsevier B.V.
Almost all three garnet types have been replaced by fine-grained, dark-brown allanite that is typically disseminated and has the same relief as andradite. The Cu content increases while Ni content decreases slightly towards the rim of garnet II and garnet III. Copper in garnet II is positively correlated with increasing almandine content and decreasing andradite content, indicating that the almandine structure, containing relatively more Fe2 +, is more suitable than andradite and grossular to host divalent cations such as Cu2 +. Nickel in garnet II is positively correlated with increasing andradite content, total Fe, and decreasing almandine content. This is because Ni2 + substitutes for Fe3 + in the Y (octahedral) position. There are unusual discrete grossular-almandine rich domains within andraditic garnet III, indicating the low diffusivity of Ca compared to Fe at high temperatures.
|Item Type:||Refereed Article|
|Keywords:||NW Iran, Astamal, Distal skarn, Garnet, Chemical zoning, Discrete grossular-almandine-rich domains, Mineral chemistry|
|Research Division:||Earth Sciences|
|Research Field:||Mineralogy and Crystallography|
|Objective Division:||Expanding Knowledge|
|Objective Group:||Expanding Knowledge|
|Objective Field:||Expanding Knowledge in the Earth Sciences|
|Author:||Gregory, DD (Dr Daniel Gregory)|
|Web of Science® Times Cited:||4|
|Deposited By:||CODES ARC|
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