关于可容纳空间和A/S的几点讨论

ccommodation is a key conception in both sedimentary geology and sequence stratigraphy. By discussing the controlling factors of depositional trends as well as the relationship between stratigraphic base level change and water depth, this paper clarifies the differences and relations between accommodation and water depth, and the relationship between stratigraphic base level fluctuation and accommodation changes. Also, this paper gives out a new definition of accommodation that accommodation is the distance between stratigraphic base level and datum, and the datum is the sediment surface of a given point at the starting time of a specified study object. Meanwhile, this paper gives out a new definition of A/S, in which A represents the rate of accommodation change; S represents the rate of sedimentation. A/S could not only judge the depositional trend in subaqueous environments, but also predict the channel pattern in subaerial environments. The new definitions derive from the original conception and its interior nature of its practical use. However, it is more clear and concise, and will cause less confusion, which will help practitioners of sedimentary geology and sequence stratigraphy to learn the notion better in order to use better in practice.