碧玄岩

稀土元素较高，分布模式呈轻稀土富集型，Eu一般为正常型与碧玄岩最接近。

The rare earth elements are higher , the distribution pattern is light rare earth elements concentration type , Eu is usually normal type , they are closest to basanite .

郯庐断裂带中段的新生代火山岩以碱性系列的碱性橄榄玄武岩、碧玄岩和霞石岩为主，其中又以钠质亚系的岩石为主。

According to the main rock-forming minerals in them , the Cenozoic volcanic rocks are mainly alkali olivine basalt , basanite and nephelinite .

原生矿产于第三纪的尧山组玄武质碧玄岩中，砂矿则分布于方山周围的水系中。

The native minerals originating from Tertiary basanite of Yaoshan formation , the placer is in water systems around Fangshan .

第Ⅰ期（年龄为34~32Ma）火山喷发较弱，形成小范围分布的白榴碧玄岩；

In Stage ⅰ( 34 ~ 32 Ma ), the volcanic eruption was relatively weak , and only small-scale of leucite basanite formed .

岩石学和地球化学特征揭示包体寄主岩为碧玄岩，岩浆没有经历明显分异和同化混杂作用。

Their petrological and geochemical characters suggest that the host rock of the xenoliths is basanite , and the magma has not experienced obvious differentiation and assimilatory contamination .

地幔橄榄岩部分熔融产生玄武质岩浆，部分原始地幔岩浆未经变异沿构造通道直接喷出地表形成碧玄岩、碱性橄榄玄武岩；

The basaltic magma was generated by partial melting of peridotites in the mantle . Basanite and alkali-olivine basalt was formed by partial primary magma along structural thoroughfare direct ejected .

主要岩石类型有橄榄玄武岩、碱性橄榄玄武岩、碧玄岩、霞石岩以及由分异作用或混染作用形成的碱性辉绿岩、拉斑辉绿岩和方沸正长岩；

These rocks consist of olivine basalt , alkali olivine basalt , basanite and nephelinite , together with alkali diabase , tholeiitic diabase and analcite syenite which have been formed as a result of differentiation and contamination .