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华南地区产于震旦纪地层中的火山岩主要见于震旦纪裂谷盆地两侧的边缘，湖南新化和广东高思火山岩为其中的二个发育地区，镜下鉴定为玄武岩系。在ＳｉＯ２－Ｋ２Ｏ＋Ｎａ２Ｏ的分类图中主要为玄武岩类，有一样品为碧玄岩类，含有较多石英杏仁体玻璃质火山岩角砾的样品为玄武质安山岩类。在ＦｅＯ＊－Ｎａ２Ｏ＋Ｋ２Ｏ－ＭｇＯ三角图中所有样品均为拉斑质岩系。样品的重元素丰度模式具大陆－初始裂谷－Ｅ－ＭＯＲＢ拉斑玄武岩的过渡特征，在Ｎｂ、Ｚｒ、Ｙ、Ｔｉ图上属板内环境。在ＴｉＯ２－Ｋ２Ｏ－Ｐ２Ｏ５三角图上显示以大洋环境为主、大陆环境为次。湖南新化拉斑玄武岩的Ｓｍ、Ｎｄ同位素特征反映岩浆来源于亏损的地幔，并受到了老基底的污染。
Volcanic rocks that originated in the Sinian strata in southern China are mainly found on the two sides of the Sinian rift basin. Two of these areas are the Xinhua and Guangdong Guth volcanic rocks, and are identified as basaltic by microscopy. In the classification diagram of SiO2-K2O + Na2O, there are mainly basalt types, and one sample is Bi Xuan rock. Samples containing more quartz almond body vitreous volcanic breccia are basaltic andesite. All of the samples in the FeO * -Na2O + K2O-MgO triangle map are of the ratonite series. The heavy element abundance pattern of the samples is characterized by the transitional characteristics of continental-initial rift-E-MORB tholeiitic basalts and belongs to the intraplate environment on the Nb, Zr, Y and Ti maps. In the TiO2-K2O-P2O5 triangle diagram shows the main ocean environment, the mainland environment times. The Sm, Nd isotopic characteristics of the Xinhua stratiform basalts in Hunan Province reflect that the magma originated from the depleted mantle and was contaminated by the old basement.