Plate Tectonics Unit Test - Science Grade 8

How were the limestone layers in the central United States deposited?

They were deposited over millions of years when the area was covered by an ocean.

What activity occurs along the Mid-Atlantic Ridge?

The South American and African plates are spreading apart, allowing magma to rise and harden into new sea floor.

Where are the oldest fossils located in sedimentary rock layers?

Oldest fossils are found in the lowest layers of sedimentary rock.

Which sectors contain the newest rock at the Mid-Atlantic Ridge?

The sectors that contain the newest rock are closest to the Mid-Atlantic Ridge.

What supports the theory concerning the age of the ocean crust?

New ocean crust is being formed at underwater locations where older crust moves away as plates move apart.

How do ocean basins form according to plate tectonics?

Ocean basins form as continental plates drift apart.

What happens at a transform boundary?

Plates slide past each other.

Where are super volcanoes typically located?

At hotspots.

How do hotspots lead to the formation of the Hawaiian Islands?

Magma in the mantle rises into the crust, forming a hotspot, and breaks through the crust, forming a volcano.

What evidence supports the theory of plate tectonics regarding the Franklin Mountains and eastern Antarctica?

Both locations contain the same types of fossils, chemically and geologically identical rocks, indicating they were once connected.