2. Ocean Shapes Earth

The ocean wears down rock and land with waves, currents, erosion, and tectonic activity. It can also build up rock and land with waves, currents, deposits, volcanic activity, and tectonic activity. The ocean is just as important to forming land as the life that inhabits it.

It is vital in global geological cycling which includes elements like carbon, nitrogen, silica and carbonate. It is because of carbon that scientists are able to age fossils. Because the ocean holds the most life, it is the largest reservoir of ‘rapidly’ cycling carbon. Unless it is deposited on a beach, eaten, or taken at the surface, most ocean life ends up eventually sinking to the bottom. Where the carbon is in it's life cycle tells scientists how old their sample is. By coring into the ocean bottom, geologists can read the past like a book.

The carbon cycle.

Erosion plays a key role in releasing minerals, like carbon, into the ocean but it also impacts the shape of the land we live on. Erosion breaks down the land through the impact of waves and the chemistry of the water or by throwing ocean debris against the rocks.

It is in part thanks to erosion that we have beaches to enjoy. Sand consists of tiny bits of animals, plants, rocks, and minerals. Most beach sand is eroded from land sources and carried to the coast by rivers but sand is also eroded from coastal sources by surf. Sand is redistributed by waves and coastal currents seasonally.


Just as erosion breaks down the land, geological movement in the ocean can also build it up again. Dense tectonic oceanic plates slowly slide under lighter continental plates which reshapes the ocean basins, continental shelves, inland seas, and the continents.

When large earthquakes happen near the coast, the ocean can restructure the surface of coastal lands with shaking, sea level changes, landslides, and tsunami wave force. The incredible force of the ocean and the tectonic plates in the ocean play a huge role in the creation of the land on earth. The land is not only connected to the ocean, it is physically shaped and moved by it.

Complete the Carving a Path Through the Mountains Assignment

Once you have completed the assignment, you can earn you badge by taking the Ocean Shapes Earth Quiz.


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