Coastal and Oceanic Landform (08. Beach and Raised Beach)

08.Beach and Raised Beach                                                               Back to Coastal and Oceanic Landform 

 Beach





  • Beaches form between the high& low water marks is planed by waves.
  • All beaches have a gradient towards the sea.
  • It varies with the size of the sediment, with gravel beaches being the steepest.
  • The beach sediment may vary from gravel in exposed locations with high sediment supply.
  • Sheltered locations are;

                                                   -Mineral
                                                   -Shell sand
                                                   -Mud
  • The beach surface is rarely absolutely flat.
  • Generally has swales and berms.
  •  In exposed locations, storm beaches typically form a sequence of ridges.
  • Once formed, the beach may be raised above sea level;
                                                          -The land rises
                                                          -The ocean volume falls.
  • The elevation of the now raised beach will depend on the balance between land movements and sea level change.
  •  The changes in sea level on a coast are complex & vary in time and space.
  •  A wave-cut platform raised above the shoreline by a relative fall in the water level.




Raised Beach






  • A raised beach called as;

                                          -Marine terrace
                                          -Perched 
  • There are beaches or wave cut plat forms raised up to shore line.
  • Coastal uplift and Quaternary sea-level has resulted in the formation of marine terrace sequences.
  • They were formed during separate inter-glacial high stands.
  • The slope inflection between the marine abrasion platform and the associated paleo sea-cliff. 
  • The shoreline angle represents the maximum shoreline of a transgression and a paleo sea level.



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