Geothermobarometry of Khunrang intrusive complex (northwest of Jiroft, Kerman province): Constraint on using mineral chemistry of amphibole to determine characteristics of parental magma

Khunrang intrusive complex (KIC), as a one of the largest complexes in the southern part of Sanandaj- Sirjan zone, is located in northwest of Jiroft in the Kerman province. The complex is mainly consists of acidic-intermediate felsic rocks of diorite, quartz diorite, tonalite, granodiorite and granite with subordinate amounts of hornblende gabbro and microgabbro as mafic members. General texture of the samples is hypidiomorphic granular; but porphyry texture with microgranular groundmass also occasionally occurs in felsic samples. Mineral chemistry studies on the amphibole crystals in both felsic and mafic parts of KIC show that they are S-Amph type and magnesio-hornblende in composition that formed in a relatively oxidized environment in an active continental margin. Plagioclases have a range of composition from labradorite (An50.4Ab49.0Or0.6) to oligoclase (An26.2Ab73.0Or0.9) with average of andesine (An36.6Ab62.6Or0.8) and bytownite (An89.6Ab10.4Or0.0) to andesine (An35.8Ab56.0Or8.2) with average of labradorite (An56.8Ab41.9Or1.3) for felsic and mafic samples, respectively. Based on geothermobarometry studies on amphiboles and also amphibole-plagioclase pairs, average temperatures of 760-783°C and 691-717 °C with pressure ranges of