摘要
Trace elements including REE (Rare Earth Elements) in fluid inclusions inlherzolite, olivine, orthopyroxene, and clinopyroxene have been determined by heating-decrepitationand ICP-MS (Element Type Inductively Coupled Plasma-Mass Spectrometry) method. Normalized CO_2fluid/chondrite data show that mantle fluids are rich in REEs, especially LREEs (Light Rare EarthElements), several times or dozen times higher than mantle rocks and mantle minerals. There areclose relationships among the REE data of olivine, orthopyroxene, clinopyroxene and lherzolite.Compared to the data of chemical dissolution method, it is believed that REE data obtained fromheating-decrepitation and ICP-MS technique are contributed by CO_2 fluid inclusions. About 60percent (mass fraction) of tiny inclusions are observed not to be decrepitated above 1000 deg C, soREE data obtained are only contributed by decrepitated inclusions. Mantle fluids rich in LREE playan important role in mantle metasomatism, partial melting and mineralization.
Trace elements including REE (Rare Earth Elements) in fluid inclusions inlherzolite, olivine, orthopyroxene, and clinopyroxene have been determined by heating-decrepitationand ICP-MS (Element Type Inductively Coupled Plasma-Mass Spectrometry) method. Normalized CO_2fluid/chondrite data show that mantle fluids are rich in REEs, especially LREEs (Light Rare EarthElements), several times or dozen times higher than mantle rocks and mantle minerals. There areclose relationships among the REE data of olivine, orthopyroxene, clinopyroxene and lherzolite.Compared to the data of chemical dissolution method, it is believed that REE data obtained fromheating-decrepitation and ICP-MS technique are contributed by CO_2 fluid inclusions. About 60percent (mass fraction) of tiny inclusions are observed not to be decrepitated above 1000 deg C, soREE data obtained are only contributed by decrepitated inclusions. Mantle fluids rich in LREE playan important role in mantle metasomatism, partial melting and mineralization.
基金
The work was financial support by National Natural Science Foundation of China (No.49972031).]
