Erosion is the natural process by which rocks and soil break down over time as water seeps into cracks in rocks to dissolve minerals, or quickly in the form of landslides.
Wind and gravity can also erode weathered materials to move them to different places, creating landscape features like earthen floodplains in river valleys, rocky coastlines and oxbow lakes.
Soil
Soil is a complex mixture of minerals, water and air as well as the remains of living things that is formed naturally through erosion and deposition processes. Erosion agents include water, wind, ice and gravity which all play their part in breaking apart rocks or soil into smaller pieces; chemical weathering occurs when rocks or minerals interact with air and water or microorganisms to alter their shape or change shape over time.
Once an eroding agent has expended its energy, its load of eroded material is then dropped somewhere else in a process called deposition. This may happen nearby such as on beaches or far off like where glacial deposits settle after they leave their sources.
Erosion is not simply destructive; rather, it helps shape landscapes into beautiful features and is fundamental for life on Earth. But erosion can also have detrimental consequences when people alter the environment by clearing away trees or plants that hold soil together.
Bedrock
Deposition occurs when erosion wears away rocks, soil, and other geological materials from one location and transports them elsewhere; this topic investigates where they end up and what landscape features result from deposition.
Physical erosion is caused by multiple agents such as water, wind, gravity and glaciers. The rate of physical erosion depends on many variables including water flow and winds as well as gravity or ice glaciers that impact glaciers – these processes may be gradual like erosion on a mountain slope or fast like river siltation in canyons. Plant growth also plays a part by breaking up or cracking rocks when they grow against them and rub against them during growth and rub-off processes.
Bedrock is the layer of solid and consolidated rock that forms the surface of an area. It may be exposed on mountaintops, along the coast or stone quarries; or hidden under layers of soil and sand. Bedrock tends to be older and harder than any material it covers.
Beaches
Beaches are coastal regions where sand collects along rocky or cliffy coastlines, and often feature an accumulation of cobbles and rock fragments known as debris lobes.
The composition and size of sediments found on beaches depends on the waves that create them. Constructive waves with gentle swash and weak backwash allow beaches to build up as more sediment accumulates; destructive waves with stronger power create steeper and longer-lived beaches that gradually recede over time.
Some beaches feature coarser-grained sediment such as pebbles, shingle or boulders for their substrate; this type of beach typically appears near cliffed areas and may even be very steep in parts.
Erosion of beaches exposes less resilient rocks and soils to strong wave action, potentially undermining coastal headlands while altering coastal shallow habitats by burying sea grasses and depriving corals of light. Furthermore, beach erosion often alters wind patterns affecting surface wind-driven processes resulting in recurrent sand drifting inland which erodes its hinterland.
Water
Erosion is a natural process that wears away Earth’s surface materials and transports them over time, often through liquid water, wind and glacial ice movement. Furthermore, weather changes may also influence erosion levels.
As they flow, streams and rivers erode the earth as they pass over it, forming flood plains, meanders, and oxbow lakes as well as canyons and valleys. Water also cuts through rock to form canyons and valleys. As more material passes down river channels at one time (called its load), more erosion takes place; most often comprising particles like sand silt or clay which make up most of their load.
Erosion can be affected by climate, topography, vegetation and tectonic activity – these elements all play a part in its severity in any landscape. Once erosion has carried materials away they’re dumped somewhere new in a process called deposition; this leads to canyons being formed from valleys, river banks and even alluvial fans and deltas!