岩石矿物学杂志2017，Vol.36Issue(3)：371-388,18.
滇东南马关木厂新生代玄武岩中橄榄岩包体的含水性
Water content of peridotite xenoliths in Cenozoic basalt from Muchang of Maguan, southeastern Yunnan Province
摘要
Abstract
Nominally anhydrous minerals,i.e.,clinopyroxene (Cpx),orthopyroxene (Opx) and olivine (Ol),from peridotite xenoliths hosted by Cenozoic basalts in Muchang,Maguan,southeastern Yunnan Province,were investigated by micro-Fourier transform infrared spectrometry (FTIR).Most of Ol and all the Cpx and Opx grains contain structural water in the form of OH.The range of the average core water content (HzO) of multi grains (＞10) in the same sample from the analyzed Muchang peridotites is 160 × 10-6～557 × 10-6,85 × 10-6 ～207 × 10-6 and 5 × 10-6～12 × 10-6 for Cpx,Opx and Ol respectively.The whole-rock water content recalculated according to mineral volume proportions varies from 46 × 10-6 to 137 × 10-6,much richer than that in the North China Craton.Elemental fractionation suggests that the peridotite xenoliths are relicts of primary mantle with partial melting.Low (La/Yb)N(0.22～0.57) and high Ti/Eu (4 076～6 772) of clinopyroxenes suggest that Muchang lithospheric mantle has undergone low mantle metasomatism by silicate melt.Apparently,the large-scale Neo-Tethys oceanic crust subduction and fluid metasomatism contributed to the rich water in Muchang,which implies that the mantle in Muchang was the new proliferative mantle and the geological evolution differed from that of the North China Craton in Cenozoic.关键词
橄榄岩包体/结构水/岩石圈地幔/木厂Key words
peridotite xenolith/structural water/lithospheric mantle/Muchang分类
天文与地球科学引用本文复制引用
朱萌,王蓉,谢志鹏,范爱玲..滇东南马关木厂新生代玄武岩中橄榄岩包体的含水性[J].岩石矿物学杂志,2017,36(3):371-388,18.基金项目
国家自然科学基金项目(41363002) （41363002）
教育部博士点新教师基金项目(20135314120008)National Natural Science Foundation of China (41363002) （20135314120008）
Doctoral Fund of Ministry of Education of China (20135314120008) （20135314120008）
