In this paper local projection and edge detection methods were used for automatic layer separation. First, phase space reconstruction was adopted for log time series, and then noise caused by nonstratigraphic factors was reduced by local projection. Edge projection was utilized to study data of highdegree membership and to detect possible layer boundary according to the loss function. Finally, the model was constructed based on local projection and edge detection. Its practicability and feasibility are demonstrated clearly by log time series data obtained in west Sichuan Province.