Volcano Practice Test 3

Which model below represents the tectonic activity that forms the Cascade Mountains volcanoes?

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Complete the Claim below, to describe why volcanic activity occurs in the Cascade Mountains.

“The Cascade stratovolcanoes are caused by __________ tectonic activity.” Choose one answer below.

• A region of no tectonic plate activity

• subduction

• spreading

• hotspot

Identify the Scientific Principle that is related to the Claim about the volcanic activity that formed the Cascade Mountains.

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  Oceanic crust pulls apart and lava erupts out, creating new ocean seafloor.

• Oceanic crust sinks into the hot mantle and is melted into magma which rises up through continental crust and forms volcanoes.

• Volcanoes form within plates due to the motion of a tectonic plate over a hot mantle plume

Using your answers to Parts 3A - 3C, connect the Evidence from the text and figures to your Claim using the Scientific Principle you selected to complete the following sentence starters.

The tectonic plates at the boundary near the Cascade Mountain are moving________________________.

• away from each other

• towards each other

• not moving at all

Construct a scientific conclusion to explain how the Cascade Mountains formed.