Tertiary volcanic rocks including andesite, trachydacite and rhyodacite with pyroclastic rocks cropped out in east of Sarbisheh at Southern Khorasan.  The main minerals in andesites are plagioclase, pyroxene, amphibole and biotite and for acidic rocks include plagioclase, quartz, sanidine, amphibole and biotite. On the basis of microprobe analyses, the composition of plagioclases in andesites r...

Arousan -e- Kaboudan area, located about 115 km northeast of Nain (south of Choupanan), is part of Central Iran (Yazad block). The Eocene volcanic rocks of the area are composed of lavas and pyroclastic rocks. The lavas can be divided into acidic (rhyodacite) and relatively basic-basic (trachyandesite, mugearite and hawaiite) rocks. The textures of these rocks are trachytic, hyaloporphyritic an...

Tertiary acidic to intermediate volcanic activities and the role of fault zones in Sarbisheh area have provided suitable conditions for the formation of bentonite, especially in pyroclastic deposits. Southeast Gondakan, Kalateh Pedaran, Golab, Golestan, Asfich, Hasan Kolangi, and Kangan bentonites in 1/100000 geological map of Sarbisheh were selected as the case study. Satellite image processin...

The studied area located in south and south western Arak town and are the part of Sanadaj-Sirjan Zone. The plutonic rocks in Astaneh and Boroujerd areas are quartz diorite, granodiorite and monzogranite. In addition to plutonic rocks, subvolcanic rocks of rhyodacite composition are present in Astaneh area. In general, in these areass mineral assemblage is the same in different units. The common...