In general, Chapter 11 is about coasts, beaches and shores i.e. the land that meets ocean waters. The difference between a shore and a coast is that the coast is a larger zone than a shore. A sandy beach is a shore, however, the coast includes marshes, sand dunes and cliffs inland of the beach. Coasts also have sandbars and troughs right of the shore. Coast, shores and beaches are active zones that are eroded by waves, winds and tectonic plate movement. Coasts are active places and the location of a coast depends on global tectonic activity and the volume of water in the ocean. The shape of a coast is developed by many processes such as uplift and subsidence, the wearing down of land by erosion, and the redistribution of material by sediment …show more content…
There are erosional coasts and those are new coasts where wind, waves and rain remove coastal material. Waves can affect the coast only where they strike, so erosion is most progressive near sea level. Erosional coasts are shaped by stream erosion, abrasion of wind-driven grit, alternate freezing and thawing of water in rock cracks, plant root probing, glacial activity, rainfall, dissolution by acids from soil slumping (sinking or settling). Coasts are classified by two terms: high-energy coasts and low-energy coasts. Erosion is most rapid on high-energy coasts while they are frequently attacked by large waves and tropical storms. Low-energy coasts are rarely attacked by large waves. Shorelines can be straightened by selective erosion and straightening occurs most rapidly on high-energy coasts. Eventually, coastal erosion forms smooth sandy shoreline. Wave refraction deposits sand sediments smoothly all over the shore and therefore creates a straight and smooth, like a parking lot, beach. Beaches consist of loose particles. The matter of fact, beaches dominate depositional coasts because features found on depositional coasts are usually sand sediments rather than rock, just as we see usually see on the beach. Beaches form when sediment like sand is transported to zones suitable for deposition, while sediment on a beach has been moved for long distances by rivers or ocean currents to its present location. Great storm waves can restructure and reshape a beach in a day, transporting thousands of tons of sediment from the beach to hidden sandbars offshore. Beaches are cut to a lower level in winter than in summer because higher waves accompany winter