摘要
在豫西伊川—汝阳两县交界地区,出露一套新生代玄武岩。该玄武岩以低硅富碱和钛为特征,属轻稀土元素富集型。玄武岩岩石化学成分比较均一,以碱性橄榄玄武岩为主,微量元素镍和铬含量低,这些特征指示了该玄武岩属上地幔低度部分熔融产生的原生岩浆快速喷出地表的产物。岩浆在上升运移过程中,没有发生明显的分离结晶和同化混染作用,起源于60～85km的上地幔范围。
The Cainozoic alkali olivine basalt in Yichuan -Ruyang of western Henan is chauacterized by the high concentration of Na2O, K2O, TiO2, LREE and the low contents of the incompatible elements: Ni and Cr. Homogeneous petrochemistry indicates that the basalt is the product of primary melts erupted at such a high speed from the mantle that neither obvious fractional crystallization nor contamination occurs during the melt migration. The primary melts are formed at the pressure of 18-25 kbar,that is ,60 - 85 km under the ground surface.
关键词
豫西
新生代
玄武岩
上地幔
岩浆
Western Henan, Cainozoic, Basalt, Upper mantle
