This type
of modeling doesn´t rely on the clime. It depends on other factors such as the
waves, the tides and the currents.
- Agents: Water is the main agent. It can´t produce erosion unless it carries different materials.
- Processes: Intense chemical weathering (thanks to the presence of water) and biological weathering (for instance: limpets, a type of mollusk, stick to rocks and erode them). The erosion caused by the waves forms:
- Cliff: Sea shores with steep slopes. Water undermines the bottom part of the rock, so it loses balance and breaks. Gravity acts and the materials fall down forming an abrasion platform.
- Arc: It is formed when the waves crash against a land rise and change their course, heading towards an area on the walls that they will erode.
- Stack: Formed by the extreme erosion of an arc. It is a vertical column of rock in the sea near a coast.
- Caves: they are formed because of the constant crash of the waves against a certain point on the rock.
Landforms
caused by transport and sedimentation:
- Beach: Places where the materials brought to the coast by the waves are sedimented. It is divided into three different parts:
- Foreshore: It´s the closest area to the sea and it floods with the
high tide.
- Berm: mound that separates the foreshore and the backshore.
- Backshore: Furthest area from the sea, with some vegetation.
- Dunes: Originated by the action of the wind on the deposited
materials.
- Bays and coves: These areas are more protected from the waves than beaches. They have a bigger curvature than beaches.
- Sandspit: It´s a type of bar or beach parallel to the coast formed by the accumulation of materials because of the process of longshore drift. This process consists of the transport of sediments by waves along the coast at an specific angle in relation to the shore line, but they go back parallel to it, in the direction of the maximum slope. Sandspits create lagoons.
- Marsh: Type of wetland (flat area saturated with seawater).
- Tombolo: Islet attached to the coast by a sand bar.
- Coral reef: Underwater structures made from calcium carbonate secreted by corals. Corals grow in warm very oxygenated and clean seas.
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