Writers : Salehinejad,Hamideh;Sadeghian,Mahmood;Ghasemi,Habibollah
Refference : 11th Symposium Of Geological Society Of Iran - Mashhad, Ferdowsi University
Publishing Year : 1386

Abstract :

Bashtine area in the west of Sabzevar, is a part of Sabzevar ophiolitic zone (SOZ). In this area, the ophiolitic host rocks have been intruded by numerous of subvolcanic domes with andesite, trachy andesite, dacite and rhyolite composition. Fragments of host rocks include tuffaceous siltstone, volcaniclastics and harzburgites found in these domes. The presence of huge volume of detritus fragments of rhyodacitic rocks that originated from these domes in Pliocene and Plio-Quaternary conglomerate, and the absence of them in the Miocene marls show that domes have been outcropped in the time – boundary of the Miocene – Pliocene or about 5 million years ago. The studied rocks have calc-alkaline nature and geochemical adakitic features. These rocks have been generated by partial melting of subducted oceanic slab in an arc subduction zone, by low rate partial melting and high pressure crystal fractionation. Also, they are supposed magmatic differentiation and contamination during ascent to the higher levels or emplacement in the ophiolitic belt.

Subject List : Adakit