Wheathering and Erosion
Weathering is the process of the breaking down of minerals and other substances. weathering has three main agents they are water, wind, and ice.
There are many ways things can be weathered. We put those ways into two categorys. They are Mechanical and Chemical. Both of them have five agents. Mechanical weathering is caused by many things. The five types of Mechanical Weathering are Release of pressure, freezing and thawing, Animal actions, Plant growth, and abraision. Release of pressure is when erosian removes things from the surface of something and causes cracks in the rock. Freezing and thawing is when water freezes and ice thaws leaving a big crack in the rock or other substance. animal actions is a agent of mechanical weathering that occurs when animals such as worms and moles dig in the earth. Plant growth is another cause of weathering. When a plant grows the roots will grow and grow and grow and will seep in to the cracks in the rock making them bigger. Abrasion is a process when particles of rock are carried by wind water or ice and wear away the surface of a rock. Chemical weathering has five agents. Water, Oxygen, Carbon Dioxide, Living organisims, and acid rain. Water is the most important factor in chemical weathering. Water weathers rock by dissolving it. Another Agent of chemical weathering is Oxygen. Oxygen can mix with iron when water is present and undergoes the process of Oxidation. Oxidation has a product that you see all the time. It is called rust. Carbon dioxide, the agent of weathering that is also a gas. Carbon dioxide dissolves in rain water and becomes a weak acid called carbonic acid. Living organisms play an important role in chemical weathering. Lichen is an example of living organisims in chemical weathering. Acid rain is caused when sulfur dioxide, carbon dioxide, and nitrogen mix with moisture in the air to form acid rain. these chemicals mostly come when fossil feuls are burned. The rate of weathering depends on the type of rock and the climate. A hot and wet climate would have more weathering going on than in a cool dry climate. An it also depends on what typr of rock it is. Such as tombstones. You know how when you see one grave stone that looks like it was the first placed there and one that looks really new but has a date like 1845. It is because the type of rock is more exposed to weathering. turns out the tombstones might be around the same age and you can't tell. |