Mr. Mohammad Reza Ghasempour, Dr. Nahid Shabanian, Prof. Alireza Davoudian, Dr. Hesam Moeinzadeh,
Volume 5, Issue 2 (12-2019)
Abstract
Gabbroic-dioritic rocks of Hurjand area in northeast of Kerman within the Posht-e-Badam block of the Central Iran microcontinent have intruded into the Precambrian-Cambrian sedimentary units of Desu Series. Amphibole, pyroxenes and plagioclase are the main minerals with granular and poikilitic textures in these rocks. Mineral chemistry studies show that clinopyroxene composition is augite and diopside. The plagioclase has a range of chemical composition from bytownite (An75.2Ab23.8Or1.1) to andesine (An40.2Ab55.9Or3.9). Amphibole crystals present in these rocks are calcic and magmatic types with chemical composition of magnesio-hastingsite. Geothermometry of Ti content in amphibole composition shows a range of crystallization temperatures of 769 to 889°C. Geothermometry of coexisting amphibole-plagioclase pair shows the crystallization temperature of 793 to 896°C. Results of the geobarometry show that amphibole crystals formed at pressure of about 6.3 to 8.8 kbar, equivalent to the depth of 23 to 30 km. Mineral chemistry studies indicate the formation of these rocks from magma of alkaline to sub-alkaline nature related to intra-plate tectonic setting.
