GEOL 110 Lecture 14: GEOL110CH11cont.
Document Summary
Irregularities in topography ocean floor and coast cause variations in wave height as it approaches shore. A single wave is called a wave front. The shape of the coast is similar underwater to that of the coastline. As the wave approaches the shore, it slows at the headland first. This causes the wave front to bend around the headland (refraction: effects of wave refraction. Wave normals, perpendicular to wavefronts pointing toward shoreline. Wave refraction causes normal to converge and diverge. Convergence: wave heights and energy increases, waves are bigger here. Plunging breakers: waves that pick up quickly, typical on steep beaches, more erosive. Spilling breakers: waves that spill gently, typical on wide, flat beaches, more likely to deposit sand. Beach form and processes: beach consists of loose material which has accumulated by wave action on shoreline, type of beach material depends on source of sand. White beaches from shell and coral (pacific islands)
