ژيوشيمي و پتروژنز سنگهاي آتشفشاني ايوسن جنوب ديلمان

Geochemistry and petrogenesis of Southern Deylaman Eocene volcanic rocks

Various volcanic rocks with Eocene ages outcrop in the southern of Deylaman. Based on of petrographic study these rocks mainly are made up of plagioclase, clinopyroxene and minor olivine and opaque mineral. Based on this study, these rocks are divided to three groups: basalts, andesi-basalts and dacites. Based on geochemistry data generally these rocks have calk alkali nature. Normalized trace element patterns in these rocks show enrichment in LREE and depletion in Ti, Nb, Zr and P. These characteristics are indicative of an arc subduction- related environment. Comparison composition of southern Deilaman volcanic rocks with word famous basaltic rocks show that these studied volcanic rocks have geochemistry signature of arc rocks and were formed in a subduction zone. Subduction signatures of these rocks can be related to old ancient oceans in this area and so slab that itʹs melting produce these rocks melts can be resulted from subduction of this crust and or from a older crust in area. Based on overall data it seems that Southern Deilaman volcanic rocks are a part of volcanic arc that are related to these subduction zones and were formed in Eocene time.