粤东北仁差盆地火山岩岩石化学基本特征

The volcanic rock chemical basic characteristics of Rencha basinin northeastern Guangdong

粤东北仁差盆地是受NNE向断裂控制的断陷盆地,火山多次喷发,其火山地貌主要表现为厚层的酸性火山碎屑岩和熔岩的堆积。火山岩由火山碎屑岩、层凝灰岩、酸性熔岩、酸性次火山岩组成。盆地火山岩岩石化学特征为:富硅、富碱且钾大于钠、贫钙,岩浆分离结晶作用程度高,属造山带(高铝)钙碱性玄武岩系列。

Guangdong northeastern rencha basin is to rupture structural control by NNE of faulted basin,volcanic eruptions many times,the volcanic geology mainly for thick layers of acidic clastic rock and lava accumulation.volcanic activity can be divided into a group,three stages,seven rhythm.volcanic rock chemical characteristic feature is： rich silicon,rich alkali,lean calcium,magma equilibrating cry stallization degree is high,belong to orogenic belt,calcium alkaline（high aluminium）basalt series.