On the basis of the study on the petrology , trace element , and isotopic geochemistry , the primary magma of volcanic rocks can be divided into two series according to their originated rocks and degree of partial melting . one is the basanite - alkaline basalt - olivine tholeiite magma series , which are generated by partial melting from spinel iherzolite ; the other is nephelinite magma - alkaline picritic basalt magma , which are generated by partial melting of the garnet iherzolite 岩石化学、微量元素、同位素地球化学证据都表明，华北、华南地区的火山岩根据源岩和局部熔融程度的不同，可以分为两个原生岩浆系列：一个是源岩为尖晶石二辉橄榄岩，随着局部熔融程度的增加，形成的碧玄岩岩浆-碱性玄武岩岩浆-橄榄拉斑玄武岩岩浆；另一个是源岩为石榴石二辉橄榄岩，随着局部熔融程度的增加形成的霞石岩岩浆-碱性苦橄玄武岩系列。
