شواهد كاني شناسي پديده اختلاط ماگمايي در سنگ هاي آتشفشاني گنبد سورك غرب استان يزد

Mineralogical Evidence for Magma Mingling in Surk Dome Volcanic Roc ks( West of Yazd Province)

The surk huge dome is a part of Plio-Quaternary Uromieh-Dokhtar Magmatic Belt lying in the west of Yazd province. The studied dome is exposed as an high elevated morphology. It consists of volcanic and pyroclastic rocks. Thermal metamorphism of Neogene conglomerate by the dome proved that the dome belongs to the Plio-Quaternary period. The lithology of the Surk dome is mainly dacite and rhyolite. The studied pyroclastic rocks have dark and rounded enclaves. The presence of rounded, dusty, absorbed and sieved plagioclases with abruptly zoning, new feldspar growth around the sieved plagioclase and rounded quartz in these rocks can be taken as evidences of magma mingling event. Opacitization of biotite and hornblende show that PH20 and f02 during rock formation were high. Based on geochemical data, the parent magma is mainly acidic, calc-alkaline and metaluminous in nature.