نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه زمین شناسی، دانشگاه هرمزگان، بندرعباس، ایران.
2 گروه زمین شناسی، دانشگاه پیام نور، تهران، ایران.
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The studied area is located in the northeast of Hormozgan Province, in the structural divisions between the Zagros and Makran zones in the Kohnouj-Rodan-Minab ophiolitic belt. This area includes ultramafic rocks such as harzburgite,lherzolite, and dunite. The main minerals of these rocks include olivine, orthopyroxene, clinopyroxene, serpentinite, and chrome spinel. According to mineral chemistry, olivine crystals have a chrysolite-forsterite composition (Fo85 to Fo89). Orthopyroxenes and clinopyroxenes have bronzite-enstatite and diopside compositions, respectivley. Clinopyroxenes have crystallized at a temperature between 1037 and 1207 and a high pressure of about 6 to 10 kbar. Chrome spinel mineral mainly has a uniform composition, with enrichment in Al2O3 and TiO2 and mantle nature. It has the lowest depletion rate and shows a maximum of 14% partial melting. The ultramafic rocks of this region are within the Alpine type. The low Al2O3 and the high #Mg in orthopyroxenes and forsterite composition (Fo85 to Fo89) of olivines with low CaO content in them show that partial melting is the most important event. It is in the formation of ultramafic rocks of this region and the formation of these rocks is tectonically compatible with oblique subduction environment.
کلیدواژهها [English]