Contrast of geochemical characteristics of subvolcanicRocks of north of Tabriz fault

Category Petrology
Group GSI.IR
Location 21th symposium on geosciences
Holding Date 21 May 2008

      In the north of Azerbaijan at the north of Tabriz fault numerous subvolcanic domes with NW-SE direction are developed that are intruded Miocene sandstones and gypseferrous red marls. Composition of rocks varies from andesite, dacite and rhyo-dacite to rhyolite and chiefly contains porphyritic texture with microlithic matrix. Oxi-hornblende and amphibole with reaction rims, euhedral zoned plagioclase with dendritic texture and margins are dominant phenocrysts, which occurred in the matrix of microlithic plagioclase, biotite and titan-magnetite.
   Initial petrological and geochemical studies in context to/regard to high Na2O/K2O ratio, Ni, Cr, Sr, Al2O3, MgO and low Y related to similar rocks indicate similarity with adakite rocks. Consider of proposed tectonic setting for these series of magmatic rock, include of melting oceanic young and hot subducted slab, initiated stage of subduction, final stage of subduction, oblique subduction with high velocity of subducted slab and rifting, detailed petrologic and geochemical studies of this subvolcanic plutons could significant help us in understanding Iran geological problems.