Coastal morphology can simply be defined as a form of beach. Coastal morphology is an ever-changing region because there are many processes that occur in it whether it is a process that originates from land and from the sea, both processes meet on the beach. The change is influenced by many things such as tides, waves, ocean currents, rock types, and others. However, simply, coastal geomorphological changes are caused by two natural events called abrasion and sedimentation.
beach classification
Abrasion is a process of coastal erosion by destructive ocean waves and ocean currents
The beach is a path or plane that extends, its height and width are affected by tides of sea water, which lies between land and sea (Thornbury, 1969). Factors affecting the shape of coastal morphology include the influence ofdiatropism, the type of rock, geological structure, the effect of sea surface rise and descent, as well as the sedimentation of land / river, land and wind erosion.In the coastal areas that still get the influence of sea water divided into 3 (three), namely:
a. Beach (coastal area), which is the area that directly gets the influence of sea water and can always be reached by tidal up and ups and downs.
b. Shore Line (shoreline), the separation path that is relatively row-shaped and relativemerupakan boundary between the area reached by sea water and which can not.
c. Coast (coast), the area adjacent to the sea and still get the influence of sea water.
The beach occurs because of the wave that hit the edge of the land without stopping, so that the erosion, destructive wave is called destructive waves.
Beach shape and type
By shape, the beach has 4 types:
- Beach Ramparts
Beach ramp is a relatively flat beach surface. Including this type of beach is mangrove beach, sand beach, delta beach. and the estuary beach.
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2.The beach is steep
The steep beach is a beach that forms the walls of a steep and steep hill, the steep beach is caused by the strains of waves that hit the beach can hit the wall of the hill is very strong, so over time resulted in steep formations due to eroded by very waves strong.
Curam beach is generally located in the mountainous area that borders directly with the sea, both parallel and cut the coastline. This type of beach is also touted as a factor that causes the shifting of shore.
3.The beach is a rock
This beach has steep sides on the cliff face because of the mountains that cross perpendicular to the beach. Flaise occurs because of the accumulation of the results of the destruction of the cliffs on the beach itself caused by abrasion or marine erosion.
4.Beach corals
Coral beach occurs when on the seabed along the coast there are coral reefs