Weathering vs. Mass Wasting
* Weathering is often compared to mass wasting - a term used in geology to describe any process that moves mass under the influence of gravity.
* Mass wasting can take many forms, from a small mudflow to a deadly avalanche.
* However, weathering is the process by which larger rocks are broken down into smaller rocks and sediments. It doesn't involve actual movement, just the preparation for movement.
* The process of weathering is unrelated to mass wasting, but it does contribute to it. When the rocks become smaller particles from the weathering process, it allows slope movement of debris to be much easier because water can penetrate these particles.
* Water exerts something called pore water pressure, which drives soil particles apart and lubricates their movement past each other, thus reducing the resisting force keeping the soil in place.
Types of Mass Wasting
* A long term process were material slowly moves downhill.
* The defining forces of gravity control creep that occurs gradually by a combination of small movements of soil and rock that are moving down the slope due to the force of gravity. The steeper the slope is, the faster the creep. It is also capable of causing landslides if the plant life on a slope loses its footing.
* The mechanism of creep can also make the soil migrate under cycles of freeze and thaw. It can also be caused by changes in temperature from hot to cold causing the soil into its way down to the bottom of the slope forming terracettes.
* Most of this activity is at rate that is so slow it is not noticeable to the naked eye.
* If mass movement has a very steep plane of sliding, it is termed a landslide. This includes rockslides, slumps and other instantaneous forms.
* If the mass wasting process resembles flowing water is called a flow. Mass wasting of this sort includes avalanches, mudflows, debris flows, earth flows and...