内蒙古喀喇沁早白垩世橄辉云煌岩岩筒

The Early Crataceous cascadite-pipe in Harqin of Inner Mongolia, China.

探寻地幔物质上涌的通道口,是大陆岩石圈研究所感兴趣的,它将为人们提供更多的岩石圈深部信息。本文报道的是在内蒙古喀喇沁黑龙潭火山颈中发现的橄辉云煌岩,其K-Ar同位素年龄为124 Ma。火山活动明显受到中生代构造活动控制。火山岩的元素地球化学特征反映岩浆来自富集地幔,在源区存在陆壳的混染作用。

120 Ma is a peak period of lithosphere thinning. The passways for upwelling of mantle or even asthenosphere matters are of interest in research of continental lithosphere, for they will provide more deep information. In this work reported are cascadites discovered in a volcanic neck at Heilongtan of Harqin in Inner Mongolia, whose K-Ar isotopic age is 124 Ma. The related volcanic activity was obviously controlled by the rift structures. The element-geochemical features reflect that the magma comes from enriched mantle and that hybridism of continental crust occurs in the source area.