Landforms are formed by movements of the earth, such as earthquakes, weathering, erosions and deposits. Many landforms are created by more than one of these processes. These are called polygenetic landforms.
Structural landforms are created through plate tectonics. When the earth shifts, landforms such as fold mountains, volcanoes and rift valleys can occur. Volcanoes are an example of a landform that can go on to produce other landforms, such as craters, calderas and lava domes.
Landforms can also occur through the process of weathering, which is the process by which sediments and rocks are broken down into soil or grains such as sand. Limestone landforms and periglacial landforms are two examples of weathering landforms.
Erosional landforms such as river valleys and coastal cliffs are formed when forces such as wind and water wear away surfaces. Erosion often takes a significant amount of time, but its effects are easily measured by examining geological evidence such as rock layers.
Depositional landforms are formed when minerals and other substances are deposited over time. In some cases, these landforms become sedimentary rocks after the deposits are altered by forces such as chemicals, heat and pressure. Examples of depositional landforms include deltas, flood plains and beaches.