摘要
本文讨论的玄武安山岩是地幔岩经局部熔融形成的高铝玄武安山岩浆在低压环境下结晶演化而成的。氧逸度和挥发分的变化是形成气孔或杏仁状和致密块状玄武安山岩韵律的重要因素。在剖面上,自下而上,岩石的SiO2、碱质、轻稀土含量增加;铁质降低。单斜辉石斑晶的成分特征表明其结晶于低压环境。斜长石中TiO2、<FeO)和辉石中NiO的含量均呈降低趋势。
In this paper, the Late-Jurassic basalt-andesite from Hatumohe Western Mount of Inner Mongolia are studies in the petrology, the mineral chemistry and the geochemistry of the rare carth elements. On the basis of the data, the basaltandesite may be incorporated into high-aluminium basalt series and is rich in silica, alkali, LREE, and poor in Fe The clinopyroxene phenocryst was crystallized under the low pressure condition. The basalt-andesite magma was derived from partical melting of upper mantle. The cyclothemic formation of amygdaloidal (base) and massive (top) basalt andesite is formed to be depended on the variety of oxygen fugacity and volatile component.
出处
《岩石矿物学杂志》
CAS
CSCD
1990年第3期213-223,共11页
Acta Petrologica et Mineralogica
关键词
玄武安山岩
岩石学
Inner Mongolia
Hatumohe
basalt-andesite
