基准面旋回与A/S比值的函数关系及地质意义

应用高分辨率层序地层学中的基准面旋回原理,对基准面变化进行了详细地分析。由于基准面的升降变化引起了可容纳空间与沉积物供给量的相对变化,相对应的可容纳空间变化率和沉积物供给率同时也发生变化,因而导致了在不同时期同一地区的地层在相序、保存程度和叠加样式上的差异,以及在同一时期内不同地区在相域上的差别。结合Cross提出的地层基准面原理以及沉积物供给量、可容纳空间变化率、沉积物供给率和沉积通量的物理属性,建立了相应的函数模型,推导说明了其函数关系式,阐述了它们之间的相互关系,总结了各自的变化规律和所代表的地质意义。本文的研究成果有助于进一步加深理解高分辨率地层层序的形成和演化,并且对于高分辨率地层层序的划分与对比,也有一定的借鉴意义。

The Functional Relation between Base-level Cycle and A/S Ratio and Their Geologic Implications

By applying the base-level cycle theory of high-resolution sequence stratigraphy, we have delicately analyzed the fluctuation of base-level cycle. The oscillation of the base level results in their relative variation of accommodation space and sedimentary alimentation. The variation rates of them have also changed, then lead to the difference of facies sequence, the degree of stratigraphic preservation and stacking pattern at the same territory in different ages, or the difference of phase area at different territories at the same age. Using stratigraphic base level defined by Cross and their physical attributions of related parameters: sedimentary alimentation, the variation rate of accommodation space, the rate of sedimentary alimentation and sedimentary fluxes, this paper has established the corresponding function models, deduced their functional equations, illustrated their relations, and generalized their variability and geologic implications. All those contribute to understand the process of sedimentary change and the high-resolution correlation and partition in high revolution stratigraphic sequence.