The basic rocks, which belong to alkali and tholeiitic magma series, enriched in LREE and LIL. The magmatic source of basic volcanic rocks was enrichment mantle being analogous to oceanic island basalts sources.

• 基性火山岩有磁性玄武岩与拉斑玄武岩两个岩浆系列，且富集LREE与LIL，其岩浆源区为与洋岛玄武岩源相似的富集地幔柱源。