Module 4: Bathymetry

Your journey across the ocean floor is complete. As you left dry land behind, you first encountered the continental margin, which is actually part of the continents on which we live. The margin is made up of the shelf, the slope, and the rise. In some oceans, such as the Atlantic, you then found yourself on the abyssal plain, the very flat floor of the deep ocean which is made of sediments. Although almost completely flat, the abyssal plain does contain some small hills called abyssal hills.

As you approached the middle of the Atlantic Ocean, you came upon a gigantic chain of mountains extending from the North to South Poles called the mid-ocean ridge. These mountain chains are found throughout the Earth's oceans wherever divergent plate boundaries occur. These are the areas where you will find the newest parts of the ocean floors. In isolated spots along these ridges, chemicals vent out of the Earth’s crust causing hydrothermal vents which, despite their toxicity, support an amazing diversity of life.

In other isolated spots along the seafloor are cone shaped mountains and flat top mountains called seamounts and guyots. Lastly, you traveled as deep as you could go to the bottom of ocean trenches which are along convergent plate boundaries mostly in the Pacific Ocean. That was some trip!