Gelifluction
Encyclopedia
Gelifluction, very similar to solifluction
, describes the seasonal freeze-thaw action upon waterlogging topsoil
s which induces downslope movement. Gelifluction is prominent in periglacial regions where snow falls during six to eight months of the year. In spring, the snow and ice melts, and the landscape is effectively inundated with half a year's worth of rainfall in the space of a couple of days. The top soil becomes waterlogged, and flows like a liquid. Because the soil now flows like a liquid, gelifluction is a form of mass movement that can occur on slopes with a slope angle of less than half a degree.
A lobe is usually measured in terms of its front (riser) and its length upslope (tread), gelifluction lobes typically have risers of up to 5m and treadsof up to 50m.
Solifluction
In geology, solifluction, also known as soil fluction, is a type of mass wasting where waterlogged sediment moves slowly downslope, over impermeable material. It occurs in periglacial environments where melting during the warm season leads to water saturation in the thawed surface material ,...
, describes the seasonal freeze-thaw action upon waterlogging topsoil
Topsoil
Topsoil is the upper, outermost layer of soil, usually the top to . It has the highest concentration of organic matter and microorganisms and is where most of the Earth's biological soil activity occurs.-Importance:...
s which induces downslope movement. Gelifluction is prominent in periglacial regions where snow falls during six to eight months of the year. In spring, the snow and ice melts, and the landscape is effectively inundated with half a year's worth of rainfall in the space of a couple of days. The top soil becomes waterlogged, and flows like a liquid. Because the soil now flows like a liquid, gelifluction is a form of mass movement that can occur on slopes with a slope angle of less than half a degree.
Gelifluction Landforms
The most distinctive landforms created by gelifluction include gelifluction lobes and gelifluction benches. The former refer to tongue-shaped deposits of geliflucted material orientated downslope that tend to form on slopes of between 10° and 20°, whereas the latter refer to terrace-like deposits forming on gentler slopes with a long axis running parallel to the slope contour. Gelifluction lobes can be further subdivided into either stone-banked or turf-banked lobes depending on vegetation cover.A lobe is usually measured in terms of its front (riser) and its length upslope (tread), gelifluction lobes typically have risers of up to 5m and treadsof up to 50m.