Basaltic lavas have been reported at the base of the Shemshak Formation in some areas of the Alborz zone. However, detail observations of geological outcrops in different areas in eastern Alborz show that these rocks in most aereas around Shahrood (e.g. Gheshlagh in Khosh Yeilagh area) and Damghan (e.g. Tazare, Talo and Kalate Rodbar) are intrusive as sill, dike and small stocks and in few area...

The Hormuz Formation is a sequence of lithologically various evaporitic–volcanic rocks in salt domes where the volcanic rocks are dominantly acidic, generally with less than one third basic volcanics. It was formed in the Late Proterozoic (640–620 Ma)/Neoproterozoic–Early Cambrian, as a result of sub-basin rifting in the northern part of the Arabian plate, throughout most of the Persian Gulf Ba...

Rich area’s sub volcanic bodies in southwest of Birjand have intruded into Upper Cretaceous ophiolite mélange.  These rocks are in diorite porphyry to monzonite porphyry range and their main texture is porphyry with microgranular groudmass. Plagioclase and green hornblende phenocrysts are made about 70% of these rocks. Plagioclases are andesine with albitic and carlsbad twining and distinct zon...

Niaz area is located at the Alborz-Azarbaijan magmatic zone in the northwest of Iran. All of the rock units in this area are composed of intermediate to acidic igneous rocks of Oligocene to Miocene age. Based on geochemical data, the mineralized monzonitic rocks in this area belong to high-K calc-alkaline and shoshonitic magma series, has a metalauminous to slightly peraluminous nature and belo...

In the southeast of Nir, south of Yazd Povince, several acidic volcanoes  rocks are exposed and form the youngest volcanic rocks in this region with dacite-rhyodacite composition. These rocks are composed of plagioclase, hornblende, biotite and quartz phenocrysts with trachytic and hyallomicrolithic porphyry texture. Based on geochemical data, the magmatic affinity of these rocks is calc-alkali...