ABSTRACT:It has been long recognized that mountain front fluvial fans and terrace risers are affected by tectonic setting,climatic changes and climatically induced base-level changes,yet it is not an easy task to distinguish them from each other.The Shanxi graben structural system provides a good opportunity to conduct such a research.The Shanxi graben system consists of several normal faults and landform basins,where the Fandai basin is the one located in the northeastern most part; the northern piedmont fault of Wutai Mountain comprises the southern margin which also controls the geomorphic units along the fault and the sedimentation process inside the basin. The field investigation reveals that there were three periods of rapid sedimentation during the late Quaternary,which typically,consist of a series of river terraces (T1,T2) and fluvial fans (F0,F1,F2).Deep into the mountain region,the sedimentation processes were represented by river terraces,while on the basin side they are visible as multiple fluvial fans.The former two periods of fan emplacement underwent strong tectonic events,leading to almost 30 m-high fault scarps.The subsequent deposits buried the downward parts of the fan and the upward parts formed flat fluvial surfaces.