Scholarlink

This study investigates the genesis and tectonic setting of the Emeishan basalt in the Hongge area through mineralogical and geochemical analyses. The basalt exhibits SiO₂ contents of 43.6–53.5%, high TiO2 concentrations (1.18–4.67%), and total alkali (Na2O + K2O) values of 1.74–6.29%, with Na2O predominating over K2O, classifying it as an alkaline series. Geochemically, the rocks display pronounced light rare earth element (LREE) enrichment relative to heavy rare earth elements (HREE) (LREE/HREE = 5.25–10.54; Lan/Ybn = 6.50–16.63), a negligible Eu anomaly (δEu = 0.82–1.05), and significant variability in large-ion lithophile element (LILE) concentrations. These findings suggest that the basalt originated from partial melting of garnet lherzolite in the lower mantle within a continental intraplate rift environment, subsequently undergoing crustal contamination and fractional crystallization during magma evolution.

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Geochemical Characteristics and Genesis of the Basalt in the Hongge Area of Western Panzhihua

  • 会议论文

  • 发表日期：

    2026年

查看全文
  • Haijun Yu,
  • Xue Wang,
  • Xiaolong Zhi,
  • Youguo Li

摘要

This study investigates the genesis and tectonic setting of the Emeishan basalt in the Hongge area through mineralogical and geochemical analyses. The basalt exhibits SiO₂ contents of 43.6–53.5%, high TiO2 concentrations (1.18–4.67%), and total alkali (Na2O + K2O) values of 1.74–6.29%, with Na2O predominating over K2O, classifying it as an alkaline series. Geochemically, the rocks display pronounced light rare earth element (LREE) enrichment relative to heavy rare earth elements (HREE) (LREE/HREE = 5.25–10.54; Lan/Ybn = 6.50–16.63), a negligible Eu anomaly (δEu = 0.82–1.05), and significant variability in large-ion lithophile element (LILE) concentrations. These findings suggest that the basalt originated from partial melting of garnet lherzolite in the lower mantle within a continental intraplate rift environment, subsequently undergoing crustal contamination and fractional crystallization during magma evolution.