The Ocean Floor Earths surface consists of land

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The Ocean Floor

The Ocean Floor

Earth’s surface consists of land both above and covered by water. The land above

Earth’s surface consists of land both above and covered by water. The land above the water contains landforms. Valleys Canyons Volcanoes Mountain Ranges Plains

The land beneath the water (the ocean floor) contains landforms as well. These ocean

The land beneath the water (the ocean floor) contains landforms as well. These ocean floor landforms include: The Continental Shelf The Continental Slope The Mid-Ocean Ridge The Rift Zone Trenches The Abyssal Plain

The Continental Margin – continental shelf & continental slope The edges of the continents

The Continental Margin – continental shelf & continental slope The edges of the continents slope down from the shore into the ocean. The part of the continent located under the water is known as the continental shelf. The width of the continental shelf varies around the edges of the continents. In some places, the continental shelf is fairly shallow, and in other places it becomes very deep, but it is not the deepest part of the ocean.

The Continental Slope The steep slope where the Continental Shelf drops to the bottom

The Continental Slope The steep slope where the Continental Shelf drops to the bottom of the ocean floor is called the Continental Slope. The depth of the ocean water increases greatly here.

Mid-Ocean Ridge On the bottom of the ocean, there is a central ridge, or

Mid-Ocean Ridge On the bottom of the ocean, there is a central ridge, or mountain range, that divides the ocean floor into two parts. These underwater volcanic mountains are known as the midocean ridge. stretching an impressive 65, 000 kilometers (40, 390 miles). The majority of the system is underwater, with an average water depth to the top of the ridge of 2, 500 meters (8, 200 feet). Mid-ocean ridges are geologically important because they occur along divergent plate boundaries, where new ocean floor is created as the Earth’s tectonic plates spread apart.

Seamounts Volcanic mountains not formed on the mid-ocean ridge are called seamounts. When these

Seamounts Volcanic mountains not formed on the mid-ocean ridge are called seamounts. When these seamounts rise above the water, they are called islands.

Rift Zone In the center of the highest part of the mid-ocean ridge is

Rift Zone In the center of the highest part of the mid-ocean ridge is a narrow trench called a rift. Underwater volcanic activity that adds mountains to either side of the mid-ocean ridge occurs at the rift zone. New oceanic crust is formed at the rift zone.

Trenches

Trenches

Abyssal Plain The Abyssal Plain begins where the continental slope flattens. The Abyssal Plain

Abyssal Plain The Abyssal Plain begins where the continental slope flattens. The Abyssal Plain is a flat or gently sloping, smooth area of the ocean floor.

Continental and Oceanic Landforms Description Continental Oceanic Low land between hills or mountains Valley

Continental and Oceanic Landforms Description Continental Oceanic Low land between hills or mountains Valley Rift Deep valley with high, steep sides Canyon Trench An opening in the surface from which lava flows Volcano Seamount and Volcanic Island Land which rises high above the ground Mountain Range Mid Ocean Ridge Wide, flat areas of land Plains Abyssal Plains

Identify the numbered ocean features 1 4 2 6 3 5

Identify the numbered ocean features 1 4 2 6 3 5

Identify the numbered ocean features 1. Continental Shelf 4. Continental Margin 2. Continental Slope

Identify the numbered ocean features 1. Continental Shelf 4. Continental Margin 2. Continental Slope 3. Continental Rise 5. Abyssal Plain 6. Seamount