MT 4 Plate Tectonics

The Mid-Ocean Ridge is a divergent fault on the floor of the Atlantic Ocean that helps explain continental drift. Which best describes where the oldest rock is on the floor of the Atlantic Ocean?

• Next to the Mid-Atlantic Ridge on it's East side.

• Next to the Mid-Atlantic Ridge on it's West side.

• At the very center of the Mid-Atlantic Ridge

• At the far edge of the ocean plate where it meets the continents

• In the center of the oceans where it is still moving

At the Mid-Ocean Ridge and active volcanoes you can find:

• fault lines

• earthquakes

• older crust

• newest crust

At which age strip in the picture will new crust form?

• 5

• 4

• 3

• 2

• 1

The similarity of fossils on different continents is strong evidence for:

• Continental drift and that land masses were once closer together

• Continental drift and that land masses were once further apart

• Plate tectonics theory of recycling crustal plates

• Alfred Wegener's theory of continental drift and divergent species

• Convection cells mixing the heat from the core to the surface of Earth

Ferromagnetic molecules make up little shavings of iron that are in rock and align themselves to magnetic north when the rock is molten and liquid. Where do we find this?

• Past the subduction zones where land and ocean plates collide

• On either side of mid-ocean ridges

• On the land under the Antarctic cap

• In the layers of rock surrounding the Grand Canyon

• In the convection cells of the mantle

Where new magma comes up through the opening at the Mid Ocean Ridge then hardens, the little iron shavings are stuck facing magnetic north when the lava hardens into rock on either side of the ridge.

• Plant fossils matching on two continents

• Animal fossils matching on two continents

• glacier scaring matching on two continents

• rock formations matching on two continents

• erosion matching on two continents

At the mid-ocean ridge new crust forms and spreads apart the plates at a rate of 1 inch per year. How long would it take for the plates to be 10 inches apart?

• 10 months

• 1 year

• 10 years

• 100 years

• 1000 years

Which description most accurately explains what is occurring in the diagram?

• If you are 600 Km from the ridge the crust is 40 million years old

• The distance from the ridge does not affect the age of the crust just the depth of the water

• The further from the ridge the younger the crust

• The further from the ridge the older the crust

When one plate slides underneath another, it ____ and forms _____.

• hardens; crust

• hardens; magma

• melts; magma

• melts; crust

This landform can occur at a divergent plate boundary.

• trench

• mountain

• mid-ocean ridge

• fault