What is solifluction mass wasting?
Solifluction is a collective name for gradual processes in which a mass moves down a slope (“mass wasting”) related to freeze-thaw activity. This is the standard modern meaning of solifluction, which differs from the original meaning given to it by Johan Gunnar Andersson in 1906.
What is solifluction geography?
solifluction, flowage of water-saturated soil down a steep slope. Because permafrost is impermeable to water, soil overlying it may become oversaturated and slide downslope under the pull of gravity.
What type of mass movement frequently forms a lobe shape at the toe of the landslide?
Slumps have a characteristic head scarp (exposed upper part of the failure surface) and a bulging toe (where material piles up). Earthflow: debris moves downslope as a viscous fluid, slow or rapid movement typically after heavy rains. Produces a scarp at the top and a hummocky toe or lobe at the end.
What is meant by mass wasting?
Mass wasting is the movement of rock and soil down slope under the influence of gravity. Rock falls, slumps, and debris flows are all examples of mass wasting. Often lubricated by rainfall or agitated by seismic activity, these events may occur very rapidly and move as a flow.
What are Solifluction lobes?
Solifluction lobes are created when the saturated active layer of soil is thawed, usually during the summer months. The gradient of the ground is important too as these lobes will only form on slopes. When the gradient changes again and flattens out, the material flow slows and is deposited in a tongue shape.
How does Solifluction happen?
Solifluction happens during the summer thaw when the water in the soil is trapped there by frozen permafrost beneath it. This waterlogged sludge moves downslope by gravity, helped along by freeze-and-thaw cycles that push the top of the soil outward from the slope (the mechanism of frost heave).
Where is Solifluction most common?
Solifluction can occur on slope less than 1°, but it is more common on slope gradients between 5° and 20°.
What is the difference between a rockslide and a slump?
A slump is a type of mass wasting that results in the sliding of coherent rock material along a curved surface. A rockslide is the sliding of rock material down a mountain.
What type of landslide occurs by falling bouncing and rolling?
Falls. Falls are landslides that involve the collapse of material from a cliff or steep slope. Falls usually involve a mixture of free fall through the air, bouncing or rolling. A fall-type landslide results in the collection of rock or debris near the base of a slope.
Where does Solifluction occur?
Solifluction is a common slope process in Earth’s cold climate regions in settings such as seasonally frozen ground at high altitudes or in areas underlain by permafrost; it is easily recognized by means of remote sensing (Washburn, 1979; French, 2007; Matsuoka, 2001) (Fig. 8.1).
Is Avalanche an example of mass wasting?
The first type of mass wasting is a rockfall or avalanche. An avalanche, also called a debris avalanche, is a mass of falling rock, but also includes soil and other debris. Like a rockfall, an avalanche moves quickly but because of the presence of soil and debris, they are sometimes moister than a rockfall.
How are Solifluction lobes formed?
Solifluction lobes are created when the saturated active layer of soil is thawed, usually during the summer months. The gradient of the ground is important too as these lobes will only form on slopes.