摘要
High-Mg(Mg#>45)andesites(HMA)within cratons attract great attention from geologists.Their origin remains strongly debated.In order to examine and provide direct evidence for previous assumptions about HMA’s genesis inferred from petrological and geochemical investigations,we performed reaction experiments between tonalitic melt and mantle olivine on a six-anvil apparatus at high-temperature of 1250–1400°C and high-pressure of 2.0–5.0 GPa.Our experiments in this work simulated the interaction between the tonalitic melt derived from partial melting of eclogitized lower crust foundering into the Earth’s mantle and mantle peridotite.The experimental results show that the reacted melts have very similar variations in chemical compositions to the HMAs within the North China Craton.Therefore,this interaction is probably an important process to generate the HMAs within crations.
High-Mg （Mg#〉45） andesites （HMA） within cratons attract great attention from geologists. Their origin remains strongly debated. In order to examine and provide direct evidence for previous assumptions about HMA＇s genesis inferred from petrolog- ical and geochemical investigations, we performed reaction experiments between tonalitic melt and mantle olivine on a six-anvil apparatus at high-temperature of 1250-1400℃ and high-pressure of 2.0-5.0 GPa. Our experiments in this work simulated the interaction between the tonalitic melt derived from partial melting of eclogitized lower crust foundering into the Earth＇s mantle and mantle peridotite. The experimental results show that the reacted melts have very similar variations in chemical compositions to the HMAs within the North China Craton. Therefore, this interaction is probably an important pro- cess to generate the HMAs within crations.
基金
supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-Q08-3-4)
the project from the State Key Laboratory for Mineral Deposits Research,Nanjing University(Grant No.15-09-08)
