The Silurian magmatism in the Abyane –Soh area (Kashan-Central Iran)



The Paleozoic volcanic rocks in the Abyane - Soh area are predominantly basaltic in composition and occur as pillow lava, massive and occasionally as amygdaloid texture. Several sedimentary layers including sandstones and carbonate rocks exposed intermittently with theses greenish-black basalts characterized by calcic-plagioclase, olivine and clinopyroxene (augite). Geochemically, they are tholeiitic-alkaline in nature and are classified as transitional series. Furthermore, the high TiO2 content as well as the great thickness of volcanics and sedimentary interlayers suggest that these basaltic rocks likely generated in an extentional settinig related to the orogeny movements in central Iran during the Paleozoic period. The low amount of HREE in the basaltic rocks is compatible with the presence of lerzolitic garnet in the source area. On the basis of some spider and geochemical correlation diagrams.It is suggested that the studied volcanic rocks originated from a similar source.