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The Ocean Floor. Features of the Ocean Floor. Continental Shelf. Zone of shallow water where the ocean covers the end of the continent. Shallow slope Where most ocean life is found. Why? Answer: Photic zone is the first 100 feet of water and allows sunlight to penetrate the water. .
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Continental Shelf Zone of shallow water where the ocean covers the end of the continent. Shallow slope Where most ocean life is found. Why? Answer: Photic zone is the first 100 feet of water and allows sunlight to penetrate the water.
Continental Slope Continental slope is a very steep slope off the continental shelf. Here, the ocean becomes very deep. Submarine canyons are carved out by underwater landslides called turbidity currents.
Continental Rise Sediments from the submarine canyons are deposited further out in the ocean. These sediments form the continental rise. It is here that the continental crust ends and oceanic crust begins.
Abyssal Plain • Alarge, flat, almost level area of the deep-ocean basin • Abyssal plains cover about half of the deep-ocean basins and are the flattest regions on Earth. • Layers of fine sediment cover the abyssal plains.
Mid-Ocean Ridge Formed by divergent plate boundary. Magma rises as plates pushed apart. Forms underwater mountain range of volcanoes. These ridges can cause sea level to rise and fall drastically.
Guyots and Seamounts Guyot: A flat-topped underwater mountain. Formerly an island that was eroded and sank into the ocean. Seamounts: Pointed-topped underwater mountain ranges that were likely volcanic. Hawaii will become seamounts and guyots.
Trenches Deepest point in the ocean. Have the most pressure. Formed from convergent boundaries where one plate dives beneath another (Subduction zone). Often form Island Arcs like Japan or Philippines.
Sediments Clastics: Sand, silt, mud, and clay found on continental shelf make up the thickest sediments. Biogenic Sediments: Calcium carbonate and Silica from organisms like forams and diatoms leave oozes on the ocean floor that form Chert (Silica from diatoms) and Chalk (Calcite from forams). Also limestone (calcite). Chemical Sediments: Nodules of manganese, copper, iron, and nickel can form and be found scattered on the ocean floor.