Na-rich microlite-glass in deep xenoliths, Liuhe, Yunnan: discovery and implications

Na-rich microlite-glass is discovered in deep-source xenoliths in sodium-rich porphyry, Liuhe village, Heqing County, Yunnan Province. Our study shows that the glass originated from mantle fluid through metasomatism. Based on clinopyroxene geothermometry and geobarometry, coupled with the time lap between the xenoliths and the porphyry host rock, it is considered that mantle metasomatism not only resulted in the enrichment of alkaline and large-ion elements leading to the concentration of ore metals and volatiles but also created a favorable condition for the generation of alkaline magmas which were intruded extensively during the Himalayan orogeny with extensive mineralization. The discovery of microlite-glass provides important evidence for a better understanding of this geologic event.