大长沙盆地火山岩岩石地球化学特征及成因研究

RESEARCH ON PETROLOGIC,GEOCHEMICAL CHARACTERISTICS AND GENESIS OF VOLCANIC ROCKS IN DACHANGSHA BASIN

本文通过对大长沙盆地火山岩岩石学、地球化学特征及同位素的研究，认为盆地盖层火山岩是双旋回式的火山喷溢产物，并且不同旋回的火山岩在岩浆成因、来源深度上是不一样的，是局部熔融的壳幔混合物；

On the basis of research on petrologic,geochemical characteristics and isotope composition of volcanic rocks in Dachangsha basin,this paper concludes that the volcanic rocks formed from magma of different genesis and depth are double cycle effusives.It is proposed that the magma forming the intermediate basic volcanics of the first cycle comes from the mixing of the partial melting of the deep crust and mantle,and the intermediate acidic volcanics of the secondary cycle are derived from the remelting of the upper crust.