贵州丹寨下、中寒武统界线划分

THE DIVISION OF MIDDLE-LOWER CAMBRIAN BOUNDARY,DANZHAI,GUIZHOU

本研究是首次对贵州丹寨凯里组界线剖面界线层的沉积岩地球化学特征进行研究 :分析沉积岩中的微量元素 ,探讨稀土元素分布模式及微量元素含量沿剖面变化的规律性 ,对沉积环境进行分析 ,结合古生物学者对界线剖面宏观生物组合和疑源类的研究所确定的划分定义 ,确定界线划分的地球化学划分方案 ,从而为丹寨下、中寒武统界线划分提供地球化学依据。并且根据对丹寨界线剖面下、中寒武统界线层化学事件研究结果 ,将界线置于 3层～ 4层之间。

The geochemical characteristics such as REE abundance patterns and variety of the trace element contents in the sedimentary rocks along the boundary section of the Lower-Middle Cambrian in Danzhai, Guizhou Province were studied.In reference to the divistion made by the paleontologists on the basis of fussile association,the aim of this paper is to provide geochemical evedence for determining and locating the boundary section of the Lower-Middle Cambrian.As a result,the boundary of the Lower-Middle Cambrian is located between Bed 3 and Bed 4.