Sea Floor Spreading And Subduction Zones Worksheet Answers

A deep ocean trench forms where the oceanic crust bends downward.

Sea floor spreading and subduction zones worksheet answers.

This is a free printable worksheet in pdf format and holds a printable version of the quiz seafloor spreading and subduction. At deep ocean trenches subduction allows part of the ocean floor to sink back into the mantle over tens of millions of years. Directions the diagram on the reverse side depicts an area of the ocean floor where different plates are shifting due to plate tectonics. Seafloor spreading is just one part of plate tectonics.

As magma flows out of the ridge the newly formed crust pushes older crust away from the ridge. Then answer the questions below. Continue pulling the magma strips until the magma sticks slide across the ocean floor. Seafloor spreading explore 1 subduction in trenches 1.

The denser lithospheric material then melts back into the earth s mantle. By printing out this quiz and taking it with pen and paper creates for a good variation to only playing it online. 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. Students should change the model so that magma is pushed out of the ridge not pulled.

You may use your book and whatever notes you have. The processes of subduction and sea floor spreading can change the size and shape of the oceans. Review answers to the seafloor structure handout by filling in the diagrams on board or using smartboard. The answer is that the ocean floor generally does not just keep spreading.

Instead the ocean floor plunges into deep under water canyons called deep ocean trenches. As years pass lateral segments of seafloor will thus share the same signature on either side of the mid oceanic ridge. 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. 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. Subduction happens where tectonic plates crash into each other instead of spreading apart. Subduction is the process by which the ocean floor sinks beneath a deep ocean trench and back into the mantle. Molten rock pushes up from the asthenosphere and pushes the plates apart at the mid ocean ridge.

Seafloor spreading is happening at b. At subduction zones the edge of the denser plate subducts or slides beneath the less dense one. This creates new ocean crust. Explain that seafloor spreading and movement is a cyclical process because it is constantly being created and destroyed.