Emergent coasts are a result of local tectonic uplift of the land surface or a fall in the elevation of sea level because of a reduction in the water volume of ocean basins. Quite often, emergent coasts have rocky coastlines with cliffs and nearly flat platforms that extend inland where older coastal plains have been tectonically raised and are now elevated above the modern land and water interface.
A very good example of an emergent coastline, because of its proximity to an active plate tectonic margin, is the west coast of North America. Parts of the Scandinavian coastline Sweden and Norway are also emergent where the land surface has been rebounding upward due to the removal of the weight of glacial ice that formed during the last Ice Age, but has since melted.
The images below show typical emergent coastlines. Submergent Coasts are those that have been flooded by ocean waters because of a relative rise in the elevation of sea level at that location. The rise in sea level can be either the result of an increase in the volume of water in the ocean basins or the result of the land surface sinking, both of which create an apparent rise in the elevation of sea level.
A common feature of submergent coastal zones is river valleys or glacially-carved valleys that have been flooded by ocean water. The Chesapeake Bay of the eastern United States is a classic example of a river valley that extended to the edge of the continental shelf during the last Ice Age when ocean waters were stored in the ice sheets.
Corrasion is when destructive waves pick up beach material e. You can reduce soil erosion by: Maintaining a healthy, perennial plant cover. Planting a cover crop — such as winter rye in vegetable gardens.
Placing crushed stone, wood chips, and other similar materials in heavily used areas where vegetation is hard to establish and maintain. As global sea level rises, the action of waves at higher elevations increases the likelihood for extensive coastal erosion.
The bare areas of a field are very susceptible to erosion. Without anything growing on them, the soil is easily picked up and carried away. The fields also experience more erosion in the winter if no plants are growing on them and they are just left as bare soil. Waves, generated by storms, wind, or fast moving motor craft, can cause coastal erosion , which may take the form of long-term losses of sediment and rocks, or merely the temporary redistribution of coastal sediments; erosion in one location may result in accretion nearby.
Coastal erosion is a natural process that continually affects the Oregon coast. Erosion becomes a hazard when human development or public safety is threatened. Beaches, sand spits, dunes, and bluffs are constantly affected by waves, currents, tides, and storms, resulting in chronic erosion , landslides, and flooding.
The effects of soil erosion go beyond the loss of fertile land. It has led to increased pollution and sedimentation in streams and rivers, clogging these waterways and causing declines in fish and other species.
And degraded lands are also often less able to hold onto water, which can worsen flooding. Natural disasters and shoreline erosion are two of the main threats that coastal communities face. Such communities are particularly vulnerable to hurricanes and tsunamis, and as more people move to the coast , the potential of such events causing catastrophic loss of life and property damage also rises.
Erosion has good and bad things associated with it. It is bad when a farmer loses the best, most fertile soil on his land near the surface to erosion because this eventually makes his or her land less productive. Erosion also has a good side. Impacts of erosion reduced ability of the soil to store water and nutrients. Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water.
A similar process, weathering, breaks down or dissolves rock, but does not involve movement. If the wind is dusty, or water or glacial ice is muddy, erosion is taking place. Some of the greatest effects of soil erosion include: Loss of Topsoil.
Obviously, this is the biggest effect of soil erosion. Soil Compaction. Reduced Organic and Fertile Matter. Poor Drainage. Submergent and emergent coastlines Download Now Download Download to read offline. Holocene sea level change. Sea Level Change AS. Holderness coastal erosion case study. Coastal Morphology. Sand Dune Ecosystems.
Storm Surges. Merry Hill - Out of town retailing case study. Dean Rusk - Secretary of State. Related Books Free with a 30 day trial from Scribd. Dry: A Memoir Augusten Burroughs. Related Audiobooks Free with a 30 day trial from Scribd. Empath Up! Ghifar Azka Azka. Avijit Biswas , Student. Caroline O'Riordan. Hassan Usaid N A. Show More. Views Total views. Actions Shares. No notes for slide. Submergent and emergent coastlines 1. Why does sea level change? Therefore sea level falls.
This can happen quite quickly. Melting of sea ice will not increase sea levels Eustatic change 5.
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