摘要
Based on the boundary differences between sequence schools in the recommended scenarios of standardization of sequence stratigraphy, this paper analyses the designed history of sequence boundaries that are respectively placed on one-eighth periodicity of sea level, lowest of relative sea level and the highest of base level. The original conceptual model of sequences, recognized by Sloss in the North American Craton between Cordilleran Miogeosyncline and Appalachian Miogeosyncline, and biostratigraphy have proved that subaerial unconformities not only wedged into sequences entirely but also partly bounded them regionally; this transforming ideal is likely to be helpful to further development for sequence stratigraphy. This paper suggests that the ideal of subaerial unconformities enclosing sequences return to that of wedging and partly bounding sequences. Moreover, it has been discussed as follows: 1) the periodicity of shoreline trajectory should be used to restrict sequence boundary; and 2) the strata relativity above and below subaerial unconformity are laterally negative to the development time intervals of subaerial unconformity.