Sea Floor Spreading Deep Ocean Trenches

The ocean floor generally does not just keep spreading.

Sea floor spreading deep ocean trenches.

The process by which ocean floor sinks beneath a deep ocean trench and back into the mantle is called subduction sub duk shun. See also continental drift a veritable legion of evidence supports the seafloor spreading hypothesis. These oceanographic features are the deepest parts of the ocean floor. The new material splits apart the old material and pushes it outward from the ridge.

In sea floor spreading new crust is added at a. The mid atlantic ridge for instance separates the north american plate from the eurasian plate and the south american plate from the african plate. Sea floor spreading and subduction work together. At a deep ocean trench the oceanic crust bends downward.

As subduction occurs crust closer to a mid ocean ridge moves away from the ridge and toward a deep ocean trench. This hypothesis traces oceanic crust from its origin at a mid ocean ridge to its destruction at a deep sea trench and is the mechanism for continental drift during world war ii battleships and submarines carried echo sounders to locate enemy submarines. Seafloor spreading occurs along mid ocean ridge s large mountain range s rising from the ocean floor. Instead the ocean floor plunges into deep underwater canyons called deep ocean trenches.

Depth below seafloor. Deep ocean trenches are surficial evidence for. Oceanic trenches are a distinctive morphological feature of convergent plate boundaries along which lithospheric plates move towards each other at rates that vary from a few millimeters to over ten centimeters per year. Sinking of oceanic lithosphere into the mantle at a subduction zone.

First related the symmetrical magnetic patterns in seafloor basalts to sea floor spreading at a mid ocean ridge. What happens to old oceanic crust as new molten material rises from the mantle. Depth below seafloor is a vertical coordinate used in geology paleontology oceanography and petrology see ocean drilling. Subduction takes place at.

Oceanic trenches are topographic depressions of the sea floor relatively narrow in width but very long. The hadal zone which includes the oceanic trenches lies between 6 000 11 000 metres 20 000 36 000 ft and is the deepest oceanic zone. A trench marks the position at which the flexed subducting slab begins to descend beneath another lit. They move the ocean floor as if it were on a giant conveyor belt.

Deep valley or underwater canyon where the oceanic crust sinks back toward the mantle subduction the process by which the ocean floor sinks beneath a deep ocean trench and back into the mantle.