Document Type : Original Research Paper


1 Department of Geology, Peyam-e-Noor University of Khoy, Khoy, Iran

2 Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

3 Fculty of Earth Sciences, Damghan University, Damghan, Iran


The Siah-Cheshmeh ophiolites at the north-northwest part of the Khoy ophiolites show a dismembered pile of metamorphic units, mantle sequence, and basaltic-andesitic lavas associated with Late Cretaceous pelagic limestones and cherts.  The basaltic-andesitic lavas can be divided into alkaline and calc-alkaline varieties. The presence of Ti-rich amphibole prisms and Ti-bearing clinopyroxenes is characteristic of these lavas. The calc-alkaline lavas are characterized by enrichment in LREE and depletion in HFSE while the alkaline lavas display positive LREE and HFSE anomalies. The interaction between mantle plumes with a spreading center can be considered for generation of alkaline basalts while a subduction zone is responsible for the genesis of calc-alkaline basalts.


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