Online encyclopedia

   Home     Add article      About



Coasts. What are coasts: different types of coasts

Picture 1 - what are coasts: facts about coasts, different types of coasts

Picture 2 -  what are coasts: facts about coasts, different types of coasts

What are coasts: Cliffs form where the sea erodes away land that slopes down into the sea. The action of the sea undermines the land, causing it to fall away and form vertical cliffs

Different types of coasts: Long shore drift occurs where a current flows parallel to the shore. Above: As the current continues in a line where the coast turns inward at a bay or estuary, it carries sand and shingle with it, building up a spit across the bay or mouth of the estuary. Below: Another effect carrying sand and shingle along the coast is that of surf and the backwash of waves. These produce a zigzag movement in the direction of the prevailing winds

Picture 3 - what are coasts: facts about coasts, different types of coasts

Different types of coasts: Many coasts are formed by land submerging. Where the features of the land run parallel to the coast, long islands are formed, as in Yugoslavia. If the features run at right angles to the coasts, long inlets form as in Ireland (click image)

What are coasts? When you sit on a beach, you can watch the waves crashing against the shore. After each wave, the water runs quickly back down the slope. The swirling water is seldom clear, because it is carrying and moving fine grains of sand. The sea also moves pebbles. If you stand in the sea, you can often feel the pebbles move under your feet. In bad storms, huge waves can shift great boulders. The sea hurls large rocks and pebbles at cliffs, battering them and dislodging big chunks of rock, which crash into the sea.

Beaches and coasts are always changing. Coastal erosion occurs when the sea is wearing away the land. Coastal deposition occurs when the sea piles up or deposits sand and pebbles to form new land. In some places, where the rocks are hard, coastal erosion may be very slow. But in Holderness, in Yorkshire, England, the sea is eroding the coast at an average rate of six or seven feet each year. Since Roman times, a strip of land about 2V2 miles wide has been eroded by the sea.
Waves often erode caves in cliff faces. Sometimes the sea cuts caves into both sides of a headland and the caves meet form a natural arch. If the arch collapses, a tall pillar of rock, called a stack, stands isolated from the coast. Some of the material worn from cliffs is swept out to sea. Some is moved along the coast and deposited to form new beaches and land areas. Sand, gravel and pebbles are sometimes piled up offshore to form long, narrow ridges called spits.

Facts about coasts - coasts are affected by rises and falls in the levels of the land and sea. If the sea-level falls, then rocky areas once under the sea are permanently exposed. Coasts of this type are called coasts of emergence. If the sea-level rises, the sea floods coastal areas. Such coasts are called coasts of submergence. The fjords of Scandinavia (one of the different coast tape) were valleys once occupied by great glaciers. After the ice melted, the sea-level rose, flooding the valleys and forming deep, long and narrow sea inlets.

You can read these articles also:

Free online world book encyclopedia

Codes and ciphers

Clouds - list of cloud types

Facts about Picasso, pictures of Picasso, Pablo



Coal gas


Coast, different types of coasts















































  @ - Online Encyclopedia