旋回年代学及其应用意义--华北地台中寒武世碳酸盐岩鲕滩高频旋回的年代学研究

华北地台中寒武世鲕滩碳酸盐岩沉积序列中发育大量分属4～7级的高频层序,依据旋回平均厚度的频率分布、不同级别旋回叠加样式和比率、沉积发育样式和跨越整个地台的可对比等特征认为,它们受控于地球轨道参数变动,是典型的米兰柯维奇旋回,其中Ⅳ、Ⅵ级分别对应于长、短偏心率旋回,时限分别为0.4Ma和0.1Ma.应用轨道旋回规则的周期间隔给出了中寒武世各级层序、地层阶和相应界面的年龄值.

Cyclochronology of Orbital Cycles and Its Implication--A Case Study on the Orbital Forcing High-frequency Cycles and Cyclochronometer of Mid-Cambrian Oolitic Carbonates in the North China Platform

A series of high-frequency (4th-6th or 7th order) cycles are sacked within Mid-Cambrian oolitic carbonate depositional successions in the North China Platform. Two ranks of cycle average thickness, stacked pattern and ratios of various cycle orders and wide correlation across the platform suggest that they could be related to the Milankovitch orbital cycles. The implication of the regularly periodities of orbital cycles is used to date the duration of strata internals,event layers and biozones et al.. The internal duration of the Mid-Cambrian stages, 3rd -6th order cyclic sequence (cycles) or boundary are estimated by the cyclost ratigraphy approach in the study.