关键词: 石英二长岩, 锆石U-Pb定年, 壳源成因, 稀土元素, 成矿作用

Abstract:

The Shouwangfen composite pluton presented the Mesozoic complex massif that was ore surrounding rock，which had close relationship with mineralization.In this study，petrography，lithogeochemistry，zircon genetic mineralogy，U-Pb chronology of uartz monzonite，lithogenesis and source region were all analyzed. Chronology results demonstrated that the 206Pb/238U weighted average age of magmatic zircon was（133.48±0.53）Ma（MSWD=0.70），and the era was the Early Cretaceous Epoch in the study area；lithogeochemistry results showed that the quartz monzonite was with the characteristic of low K₂O/Na₂O（0.74~0.89），low P（P2O5=0.09%~0.40%），higher A/CNK（1.24~1.38）and it belonged to the alkali peraluminous rock.Moreover，rare earth element content is higher （262.14×10^-6~279.83×10^-6） with enrichment of light rare earth，∑LREE/∑HREE=12.12～17.41，and the partition curve tended to the right gently.The abnormal of Eu and Ce was not obvious（δEu=0.83～1.26，δCe=0.78～0.93），which was similar to the characteristic of rare earth element in upper crust，and it was a kind of typical crust source genetic types.Therefore，after comprehensive analysis，the coupling relationship between mineralogenetic epoch and geochemical characteristics，magmatic emplacement age of quartz monzonite should represent the regional response of large-scale magmatic evolution and mineralization during Mesozoic in the east of north China.

Key words: quartz monzonite, zircon U-Pb dating, crustal source cause, rare earth element, mineralization