中国山东昌乐地区碱性玄武岩刚玉中记录的岩浆不混溶作用

摘要

Abundant melt- and fluid inclusions occur in corundum megacrysts of alkaline basalt from the Changle area, Shandong province, eastern China. One type of melt inclusions, i.e. multiphase melt inclusions ( glass + bubbles + daughter minerals) were identified ,which occur along growth zones of host corundum megacrysts. Microthermometry and laser Raman microprobe analysis were performed on the melt inclusions. The bubbles within the melt inclusions are confirmed to be CO2-rich phase and the daughter minerals are probably silicates, such as augite and okenite. The results of high temperature homogenization experiment strongly suggest that two immiscible melts, i.e. a H2O- and CO2-rich melt and an anhydrous and CO2-poor melt were trapped by melt inclusions in corundum megacryst.