It is the process of breaking particles or things down into smaller particles such as a large rock becoming sand. Erosion always happens in a downward manner. Erosion happens everyday around the world and is very simple. When you take a rock and whip it to the wall and several pebbles break away from the rock that is called erosion and you were the cause for it (a living object).
Erosion or Weathering can happen in two different ways. There is mechanical weathering and chemical weathering. An example of mechanical weathering is when you kick a rock on the ground, it breaks, an example of chemical weathering is when you pour acid onto a rock, and it starts to melt. Most of the time you can tell if a rock has been chemically eroded or mechanically eroded by the colour of the rock. If the colour has changed, it has probably been chemically eroded.
Water erosion is the most important way of erosion and the most common. Even raindrops that hit the ground move tiny pieces of soil and therefore create erosion. Water flowing down a stream also continuingly erodes soil. The higher speed of the water flowing down the stream the bigger and faster it transports objects. Although a stream does not have to be fast to erode soil, small and thin sand can be transported by streams that are moving as slowly as ¾ mp/h. The flowing water in the stream erodes water in three different parts of the stream that include the sediment and small particles at the side of the stream. Another part is the bottom of the stream where it becomes deeper and the edges of the stream.
Wind erosion is most common in desserts and sometime creates sand dunes. It also occasionally erodes rock and sand. It first elevates small particles and moves them to another region. This type of erosion usually happens in places where there is less rainfall resulting in little vegetation.
Gravitational erosion occurs when the sediments, rock or soil move downward in a slope movement from higher levels to lower levels due to the force of gravity. An example of gravitational erosion is landslides.
Ice erosion is erosion caused by ice and includes erosion caused by glaciers. The power of ice erosion is a bit greater than the power of water erosion but since there is more water in its liquid state, it creates more erosion on the earth. Glaciers scrape the ground beneath them and around them taking out the rocks under or beside them when they move. In addition, when the frozen water in cracks expands, they break the rock; this is called the Freeze Thaw.
Coastal or Shoreline erosion is the erosion caused by waves in oceans or other massive bodies of water. The strengths of these waves are tremendous and big storm waves can produce up to 2000 pounds of pressure which is easily enough to break rocks. This is the main reason why all beaches have sand in or around them.
Water is an agent of mechanical and chemical weathering because when water passes over or through rock, it dissolves some minerals and carries them away changing the makeup of the rocks and therefore creating chemical weathering. In addition, when soil is washed away by the river, the rocks pounded in by the river, and the rocks hit by the waves are going through mechanical weathering.
Sloping land erodes more quickly than flat land because gravity pulls down the sediments, rock or soil from a higher elevation to a lower one because the ground is at more of an inclined level.
As the bedrock is being weathered small rocks or sediments fall off deepening the subsoil. While the subsoil is also being weathered by plant roots and small burrowing animals, such as moles and worms. As a result of this process, the op of the subsoil becomes the topsoil. (This may take thousands of years)
