Canyons are some of the most immediately recognizable formations created from water. Rivers that are elevated above their inlets in lakes or the ocean exert force on the land, resulting in erosion. The higher the river is above the land, the greater force the river exerts. When the river reaches what is called the baseline elevation, which is the elevation at which the river matches the elevation of the inlet, the erosion slows. By that time, the river has worn a groove in the land known as a canyon. How deep the groove cuts into the land is determined by how high the river was flowing above the inlet.
Deltas are masses of land created by sediment accumulation at the mouths of rivers. These deltas can be created where a river empties into an ocean, a sea, a lake, or even an area of arid land. The sediment is deposited when the fast flow of the river is slowed by the relatively slow movement of the body of water where the river enters. The difference in flow causes sediments to sink. Eventually the sediment accumulates and a landmass is formed.
Glaciers are rivers of ice that move slowly down a drainage path, carving out valleys and rock formations as they go. Ten percent of the land worldwide is covered by glaciers, and 75 percent of the world's freshwater is contained in glaciers. Past glaciers from ice ages carved out several well-known bodies of water today, such as the Great Lakes, and they continue to shape the land today with their slow movement.
Chemical weathering happens when chemicals from flowing water settle into cracks and erode the rock. How the weathering happens depends on the makeup of the soil, as well as the mineral content of the water. One example of a landform created by this process is Carlsbad Caverns. Carlsbad Caverns were created when running water encountered hydrogen sulfide gas from underneath the Earth's surface. The acid gradually ate away the limestone bedrock, creating the massive caverns that exist today under the Eastern New Mexico desert.
