Geochemistry of tertiary volcanic rocks in the tehran region, southern flanks of central alborz Mountains

Tertiary volcanic rocks are found in the southern flanks of central alborz mountains, in the north oftehran. their composition ranges from basalt to rhyolite. they range from low-k rocks to calk-alkaline,high-k .calk-alkaline and shoshonitic series and show subduction-related geochemical characteristics.investigation of chemical analysis of major oxides and a vast range of trace elements of the rock amples of the region show that geochemical characteristics of these rocks have great similarities with those of volcanic arcs in the destructive plate margins, more enrichment in alkaline, alkaline earth elements, and th with respect to n-morb and depletion in hfse (ta, nb, zr, and hf) relative to lree are characteristics of the rocks of this region. the volcanic rocks are thought to be derived from a homogeneous mantle source modified by slab-derived melts and/or fluids and a small fraction of oceamc sediment.