The old crust gets pushed to the.
Sea floor spreading and subduction zones worksheet answers.
The denser lithospheric material then melts back into the earth s mantle.
As magma flows out of the ridge the newly formed crust pushes older crust away from the ridge.
Explain that seafloor spreading and movement is a cyclical process because it is constantly being created and destroyed.
As years pass lateral segments of seafloor will thus share the same signature on either side of the mid oceanic ridge.
Molten rock pushes up from the asthenosphere and pushes the plates apart at the mid ocean ridge.
The answer is that the ocean floor generally does not just keep spreading.
Begin by labeling the parts draw an arrow to indicate which feature you mean.
Continue pulling the magma strips until the magma sticks slide across the ocean floor.
Subduction is the process by which the ocean floor sinks beneath a deep ocean trench and back into the mantle.
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Refer back to the demonstration that you performed during the engage portion of the lesson to demonstrate this.
Where there are deep ocean trenches subduction takes place.
Students should change the model so that magma is pushed out of the ridge not pulled.
Instead the ocean floor plunges into deep under water canyons called deep ocean trenches.
The processes of subduction and sea floor spreading can change the size and shape of the oceans.
This creates new ocean crust.
Directions the diagram on the reverse side depicts an area of the ocean floor where different plates are shifting due to plate tectonics.
Then answer the questions below.
By printing out this quiz and taking it with pen and paper creates for a good variation to only playing it online.
At subduction zones the edge of the denser plate subducts or slides beneath the less dense one.
Subduction happens where tectonic plates crash into each other instead of spreading apart.
You may use your book and whatever notes you have.
Review answers to the seafloor structure handout by filling in the diagrams on board or using smartboard.
As the ocean seafloor spreads the newly formed floor will adapt a specific magnetic signature according to the earth s magnetic pole at that time.
A deep ocean trench forms where the oceanic crust bends downward.
While new earth is being born at mid ocean ridges by seafloor spreading in other areas earth is being destroyed at deep ocean trenches by subduction.
The two processes of seafloor spreading and subduction work together to constantly recycle and renew the earth s crust.
Seafloor spreading is happening at b.