Writers : Shojai,Hamidreza;Mahdizade Shahri,Hoseyn;Sadeghian,Mahmood
Refference : 11th Symposium Of Geological Society Of Iran - Mashhad, Ferdowsi University
Publishing Year : 1386

Abstract :

In the w-nw of Torbat-e-Heidarieh pliocen pyroxene andesite outcrop Wich with showing prismatic structures are one of the beautiful and unique phenomen in this region. lenght of prismatic culomn reache upto 20 meter. these andesite rocks suffered faulting,choloritization,epidotization and bentonitization affected by tectonic and hydrothermal activities. due to limitation of variation in mineralogy they have very limited range of chemical composition(61 to 63%Sio2).the studied rocks have the characteristics of medium potassic calc alkaline and hight enrichement of LILE .regular pattern of REE variation is indicate of uniformity producing magma of these rocks. Geochemical features among of negative anomaly Ti,Ta,Nb and positive anomaly Th,Rb and Cs accordance with subduction procedure and crustal assimilation. therefore these rock produced from melt fractionation subducted oceanic slab or metasomatized mantle wedge wich during an extensional tectonic regime have been ascented to upper level of the crust and flow on the earth surface.

Subject List : Magmatic Rocks