COASTAL EROSION

COASTAL EROSION

1. ABRASION

   • WHEN WAVES ADVANCE THEY PICK UP SAND AND PEBBLES. THE MATERIAL IS HURLED AT THE CLIFF- CHIPPING AWAY THE ROCK

2. HYDRAULIC ACTION

   • AIR = TRAPPEDUNDER HIGH PRESSURE AS WAVES ADVANCE, AS WAVES RETREAT THE AIR EXPLODES OUTWARD, GRADUALLY FRACTURING ROCK

3. CORROSION

   • WHEN CLIFFS= FORMED FROM ALKALINE SEDIMENT- SOLUTION BY WEAK ACIDS ERODE THEM

4. ATTRITION

   • GRADUAL WEARING DOWN OF ROCK
     • MAKES ROCKS MORE SMOOTH AND ROUND

5. LANDFORMS CREATED BY COASTAL EROSION

   • HEADLANDS AND BAYS
   • CLIFFS
     • ERODED BY HYDRAULIC ACTION, ABRASION.
   • STACK AND STUMPS
     • ARCH BECOMES UNSTABLE LEAVING A STACK, ITS ERODED FURTHER TO A STUMP
   • SHORELINE PLATFORMS
     • EROSION= CONCENTRATED AT THE HIGH TIDE LINE. CREATING A WAVE CUT NOTCH. IT BECOMES BIGGER AND ROCK ABOVE BCOMES UNSTABLE AND COLLAPSES. THE NOTCH MIGRATES INLAND AND CLIFF RETREATS LEAVING A SHORELINE PLATFORM
   • ARCH
     • TWO CAVES EITHER SIDE OF HEADLAND IS ERODED