TY - JOUR ID - 55053 TI - Magmatic Origin and Tectonic Setting of the Eocene - Oligocene Volcanic and Plutonic Rocks from the Zand-Abad Area, NW Ahar (Tarom-Qaredagh Zone) JO - Scientific Quarterly Journal of Geosciences JA - GSJ LA - en SN - 1023-7429 AU - Azimzadeh, Z. AU - Emami, M. H. AU - Hajialioghli, R. AD - Department of Geoloy, Natural science faculty, University of Tabriz, Tabriz, Iran AD - Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran AD - Department of Geoloy, Natural science faculty, University of Tabriz, Tabriz, Iran. Y1 - 2011 PY - 2011 VL - 20 IS - 79 SP - 113 EP - 120 KW - Dilatory Creep Down KW - Post-Collision Activity KW - Partial Melting KW - Fractional Crystallization KW - Magma mixing KW - Crustal contamination KW - Hybrid Magma KW - Zand-Abad KW - Tarom- Qaredagh zone DO - 10.22071/gsj.2011.55053 N2 - The Zand-Abad area is located in NW Ahar of north Azerbaijan. Magmatic rocks in this area consists of granitoids including monzogranite, granodiorite, monzonite and syenogranite as well as mafic rocks mainly diorite and associated extrusive rocks as andesite, trachyandesite, dacite, trachydacite, rhyolite. Subvolcanic rocks are porphyritic diorite and porphyritic monzodiorite. According to the different geochemical studies, the tectonic environment of Zand-Abad volcanic and plutonic rocks is determined as continental arc setting related to dilatory creep down subduction. This will be interpreted in relation with the Neotethyse post-collision activities. Considering the mineralogy and chemical evidence, we suggest that the Zand-Abad magmatic rock types (i.e. volcanic, sub-volcanic and plutonic rocks) have been derived from single magmatic source and undergone fractional crystallization, magma mixing and crustal contamination, resulting from hybrid granitoids. Magmatic series of the different types of magmatic rocks is alkaline. Calc-alkaline and shoshonite property of some samples is interpreted related to magma mixing and crustal contamination processes.   UR - http://www.gsjournal.ir/article_55053.html L1 - http://www.gsjournal.ir/article_55053_2b1ce1420e949e7bac585a127ca68c06.pdf ER -