Studies on genesis of chromite and PGE in Naein ophiolite melange

زمین شناسی اقتصادی

Article 2, Volume 3, Issue 2 - Serial Number 5, February 2012, Pages 111-125   

Document Type: Research Article

DOI: 10.22067/econg.v3i2.11438

Authors

Reza Shamsipour Dehkordi¹; Maryan Sadeghi²; Zohreh Gholami Fesharaki^{* 2}

¹Isfahan

²Khorasgan Branch, Islamic Azad University

Abstract

Nain ophiolite melange is located 140 Km east of Isfahan. Based on the geological studies, this area belongs to Mesozoic ophiolite of Urumieh – Dokhtar zone, west of central Iran. Country rocks are pridotite and serpentinized pridotite. The pridotite rocks are composed of Harzburgite, Lherzolite and replacement Dunite which is belong to spinel pridotite facies.Paragenesis of ore minerals are Chromite, Irarsite, Magnetite, Hematite, Pentlandite, Millerite, Chalcopyrite, Pyrite, and Covelline. Geochemical surveys of host rock and chromite show tholeiite series of magma and alpine type chromite. PGE (Ir, Pt, Pd, and Os) are enriched in chromite. REE spider diagram pattern show the processes of boninitic magma and partial melting.

Keywords

Nain; Chromite; PGE; Ophiolite

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