Petrology and Geochemistry of Soltan Abad (Sabzevar)Granitoid

   Abstract:
      The area which was studied in this paper, is located in Sabzevar(south of Soltanabad), part of Ophiolite belt of north Sabzevar. In this area besides colored melange, the Upper Cretaceous volcanosedimentary, Pre-Eocene granitoides and Soltanabad metamorphic complex, Eocene sedimentary rocks and Oligo-Pliocene dacitic domes can be seen. Compositional of granitoides that has intruded in metamorphic complex is as following: granodiorite, tonalite- trondhjemite, syeno-diorite, quartz-diorite and series of acidic dykes with pegmatoide texture. Quartz, plagioclase, epidot and muscovite are the major minerals of granitoides and amphibole, alkali feldespars, cholorite, sphene,calcite, and opaque minerals are the minor minerals of the those rocks. Mineralogical and geochemical reasons and tectonic setting diagrams represent the similarity between granitoides rocks of the region and orogenic rocks of the tectonic areas and magmatic island arc(IAG). Genetically speaking granitoides of the area are of I-type and according to the Castro et.al. genetical classification are of M to Hm-type and more probably granitoids are originated from fractional crystlization of mantel source hydrous basaltic magma.