SHOSHONITIC, MONZONITIC PLUTON NEAR MURMANO, EASTERN CENTRAL TURKEY - A PRELIMINARY NOTE

 The major and trace element composition of three series of samples from the Murmano pluton (Divriği-Sivas), eastern central Turkey, has been investigated in this study. Element distribution patterns as shown in variation diagrams favour the hypothesis that the pluton has a composite character, consisting of a number of intrusive bodies, representing separate magma batches. Earlier geochronological investigations suggest that the Murmano pluton postdates the ophiolite obduction in the area. Mineralogical criteria and the chemical data presented here indicate that the rocks are I-type plutonic rocks which have many characteristics of the calc-alkaline rock series for which current classification diagrams indicate an active subduction zone setting. High total alkalies versus SiO2 , K2O versus SiO2 , K2O/Na2O, Rb, Ba, Al and Fe2O3 /FeO, and low TiO2 suggest that the pluton has a shoshonitic character

SHOSHONITIC, MONZONITIC PLUTON NEAR MURMANO, EASTERN CENTRAL TURKEY - A PRELIMINARY NOTE

 The major and trace element composition of three series of samples from the Murmano pluton (Divriği-Sivas), eastern central Turkey, has been investigated in this study. Element distribution patterns as shown in variation diagrams favour the hypothesis that the pluton has a composite character, consisting of a number of intrusive bodies, representing separate magma batches. Earlier geochronological investigations suggest that the Murmano pluton postdates the ophiolite obduction in the area. Mineralogical criteria and the chemical data presented here indicate that the rocks are I-type plutonic rocks which have many characteristics of the calc-alkaline rock series for which current classification diagrams indicate an active subduction zone setting. High total alkalies versus SiO2 , K2O versus SiO2 , K2O/Na2O, Rb, Ba, Al and Fe2O3 /FeO, and low TiO2 suggest that the pluton has a shoshonitic character

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