Longitudinal profiles of the gullies in different tectonic settings and different evolutionary stages show different morphological forms which can be fitted ordinarily by such mathematical functions as linear function

exponential function

logarithmic function and power function. These forms reflect the response of the gullies to the factors such as the time

the climate

the bedrock of the riverbed and the tectonic movement. Based on DEM data

64 gullies across the Huoshan piedmont fault are extracted and their profiles are fitted by four types of mathematical functions above. The bestfitting mathematical function for each gully is selected and the responding characteristics of the gullies to the tectonic movement of the fault are analyzed. The result shows that the gullies are in their infancy which is exhibited by their linear forms or the exponential forms with very small concavity. This is due to the response of the gullies to the constant normalfault movement of the Huoshan piedmont fault since Pliocene

especially the strong activities with short interval in Holocene.