Mountain and Hillslope Geomorphology | Processes, Transport, Deposition and Landforms: Controls on Rates of Soil Creep

Hilly upland landscapes are cloaked in a thin layer of soil derived primarily from the underlying parent material. This soil, home to much of Earth’s terrestrial biota, is physically transported by slope-dependent processes driven by bioturbation, freeze-thaw and wet-dry cycles, as well as chemical weathering. Understanding how Earth’s surface evolves under changing climatic, tectonic, or anthropogenic forces thus includes understanding how these physically mobile upland soils are produced and transported. Creep subsumes transport processes thought to be linearly proportional to slope and significant effort can go into quantifying it. This chapter provides a short overview of the conceptual framework for models of soil creep, as well as results from some studies that have characterized external controls on creep rates across a range of landscapes. Soil in this context is also termed regolith by some workers and is produced and transported by very different processes than those active on agricultural or lowland landscapes. While creep sensu stricto may occur across a wide variety of landforms and sediment types, we focus here on creep as a process that transports soils on hilly landscapes. More For the studies covered we summarize the important findings, and we conclude by emphasizing that despite extensive measurement difficulties in quantifying creep, it is an important hillslope process requiring continued examination.