2Ocean floor FeaturesOcean Basin- This is the actual depression in Earth’s surface that holds the ocean water
3Continental ShelfThe gradual sloping end of a continent that extends under the ocean
4Continental SlopeThe continental slope drops more steeply, and extends from the outer edge of the shelf to the ocean floor
5Continental RiseA gentle slope with a generally smooth surface, built up by the shedding of sediments from the continental block, and located between the continental slope and the abyssal plain.
6SeamountThese are underwater mountains/volcanoes that do not break the surface of the ocean.
7Abyssal Plains The abyssal plain is some of the deepest parts of the ocean, andsome of the flattest parts of Earth
8Abyssal plainsAbyssal plains are flat or very gently sloping areas of the deep ocean basin floor. They generally lie between the foot of a continental rise and a mid-oceanic ridge.
9Volcanic IslandsWhat is the tallest mountain in the world?
10If you said Mt. Everest You’re WRONG!!! While Everest is the “Highest” (above sea level), the volcanic mountain island Mauna Kea is actually taller from base to peak!Mt. Everest is 8,848 m (29,028 ft), but Mauna Kea is 10,203 m (33,476 ft) from it’s base in the Pacific ocean.
11A Volcanic IslandIs formed by volcanic eruptions. The lava continues to pile up and harden and the mountain/island breaks the surface of the ocean.
13The Mid Ocean Ridge Is between 70,000 and 80,000 km long Is a continuous chain of undersea mountains that runs all around the worldIs the longest mountain chain on EarthForms new ocean floor as lava erupts through the Earth’s crust
14What causes the Mid Ocean Ridge? Parts of Earth’s crust—which are called crustal plates—are constantly moving.When these plates spread apart, they allow the hot magma to enter the ocean floor.As it enters the ocean and cools, it solidifies, and forms new ocean floor.
15Ocean TrenchesOcean trenches are like canyons on the bottom of the ocean floor. They are some of the deepest parts of the earth. Some bottoms of trenches haven’t even been explored yet.
16Oceanic TrenchesThe oceanic trenches are hemispheric-scale (one hemisphere to another) long but narrow topographic depressions of the sea floor. They are also the deepest parts of the ocean floor.
17The Mariana TrenchThis is the deepest trench we know of; it is over 11km deep.It is located in the Pacific Ocean. Most trenches are in the Pacific Ocean.Mt. Everest could easily fit in the Mariana Trench, and there would still be over 2000m of water over it!
18How deep is the ocean? The depth of the ocean is extremely variable. The Ocean has an average depth between 3 and 4 kilometers.The deepest point we know of is the Mariana Trench (about 11km).
19How do we know how deep the ocean is? There are several methods that have been used; can you think of any?- sounding- SONAR- diving- submersibles- Remote Underwater Manipulator- Satellites- Gravity Mapping
21Did you know we map the ocean floor? Why do we map it?So ships know the best travel routes.So we can understand the different depth of the ocean and the different effects it has on life, as well as the minerals that are available.So we can better understand the formation of the Earth, and all of the valuable resources it has.
22The type of map we use is called a Topographic MapTopography is the study of the layout of the land.How is this different than a regular travel map?Where else would you use a topographic map?How do they work?Road mapTopographic map
23Ocean Floor Topography When we discussed all the different sections of the ocean floor, we were discussing the subsurface topography of the ocean.