Abstract: The paper analyzes the physical properties of pattern characteristics which are displayed on typical Acoustic Sea-bed Profiling Records (ASPAs) in the areas of Changjiang Estuary and the East China Sea. Nine pattern charac- teristics are summarized and it is shown that 9 geographical categories can be determined by 4 pattern characteristics. Based on the above analysis, a Bayes-based pattern characteristics classifier for interpretation of ASPRs is developed.