Morphology of Alluvial Fan Longitudinal Profiles in the Parlung Tsangpo Basin

The longitudinal profile (LP) of an alluvial fan is a fundamental morphological feature that records formation processes and distinguishes fan types. Here, we quantitatively analyze LP morphology using data from 18 alluvial fans in the Parlung Tsangpo Basin (PTB) in southeast Tibet—an alpine valley basin hosting fluvial, colluvial, and debris-flow fans (FF, CF, and DF) shaped by distinct dominant processes. The data include the geomorphological characteristics of alluvial fans (location, area, length, mean slope, etc.), longitudinal profile concavity, local slope variability parameters, and corresponding channel longitudinal profile characteristics.This work aims to clarify morphological differences in the LPs of distinct alluvial fan types and provide data support for fan type identification.