The primary research methods in geology remain based on observation and experience. However, the logging data are of fine continuity and high resolution. The theoretical foundation of stratigraphic sequence identification consists of the complexity and relative consistency of sedimentary cycles, the continuous and nonperiodic characteristics of logging curves, and the multi-resolution and time-analysis characteristics of the wavelet transform. The Xujiahe logging data with the highest resolution and best continuity has been divided into three stratigraphic sequences and eighteen subsequences as a case study.