The Ocean Floor
The ocean floor is made up of various landscapes including mountains, valleys, and plains. These underwater surfaces of the ocean floor are located from the shallowest part of the ocean to its deepest part.
The continental shelf is the underwater edge of the continent. It extends from the shore to a depth of about 600 feet and has a gentle slope. About 50 miles from the shore is a steep slope called the continental slope. The continental slope leads from the continental shelf toward the sea floor and is also deeper than the shelf.
About 12 or 13 miles away from the shore into the ocean is the continental rise. The continental rise is a buildup of sediment and sand on the ocean floor at the bottom of the continental slope. It is mostly sand and mud that stretches from the slope down to the deep-sea floor.
One of the flattest places on Earth is at the end of the continental rise. The abyssal plain are large, flat lands that cover almost half of the ocean floor. These were formed when most of the hills and valleys at the bottom of the ocean were buried under a layer of sand and mud long ago.
There may also be a huge underwater mountain called a sea mount. The peak rises hundreds of miles above the ocean floor. Seamounts are also volcanoes and was formed in the same way as a volcano on land. Hot molten rock rose from inside the Earth's surface and cooled to a solid. Sometimes a sea mount may appear as an island. The Hawaiian Islands are an example of a chain of islands formed by sea mounts.
There are also trenches located on the ocean floor. An ocean trench is a V-shaped valley that is long and narrow and are the deepest points on Earth. They may extend 5-6 miles below sea level. Mount Everest would fit inside the largest trench and would still be over a mile below the surface of the Earth. The largest deep sea trench is about 7 miles deep. Trenches are so deep, sunlight will never reach the areas.
In the middle of the Atlantic Ocean, there is a huge mountain range rising above the ocean floor. This is known as the mid-Atlantic ridge. The mid-Atlantic ridge is part of a chain of mountains called mid-ocean ridges. These ridges wind its way through all of the world's major oceans.
The mid-Atlantic ridge extends the entire length of the Atlantic Ocean. The mountain ranges were also formed by volcanoes and the molten rock that cooled and hardened.
The ocean floor is also home to many sunken ships and other objects. A well-known cruise ship, the Titanic lies on the Atlantic floor almost 2.5 miles below the surface.
Finally, the ocean floor is home to hot springs called sea-floor vents. The vents are formed when seawater trickles down into newly formed ocean crust. Eventually, the water becomes saturated with minerals and it boils out of a vent in the crust.
In summary, the ocean floor is a vast area made up of various landforms called the continental shelf, slope, and rise. There is also the abyssal plain which is the flattest place on Earth. Other land forms include sea mounts, ocean ridges, and ocean trenches. The ocean floor is also home to manmade objects like a sunken cruise ship called the Titanic.