Field observation and analysis of the DEM of Western Sichuan Plateau indicate that, there are two planation surfaces and one erosion surface in Western Sichuan Plateau.

• 野外地质地貌调查和对川西高原DEM的分析结果表明，川西高原存在两级夷平面和一级剥蚀面。较高的一级海拔5100m左右，分布在山脉的顶部，称山顶面；