Plate motion

Fossil remains of Glossopteris (an extinct plant with large leaves) have been discovered in India and Australia. When they were living, all the Glossopteris were located together on land, but now the Glossopteris fossils are separated by an ocean. What could explain how these fossils got so far apart?

• India and Australia are parts of different plates. The plates slowly moved apart as new plates from underneath got added between them over millions of years.

• India and Australia are parts of different plates. The plates slowly moved far apart as soft, rock from underneath got added to the edges of the plates over millions of years.

A team of geologists wants to study hard, solid rock under the surface of Earth. The team is considering drilling down in the North Atlantic Ocean (1) and in Sierra Leone (2). Where will the team find hard, solid rock?

• only under 2, because Earth’s outer layer is made of hard, solid rock under continents but not under the ocean

• under 1 and 2, because Earth’s entire outer layer is made of hard, solid rock

The youngest rocks on the ocean floor are typically located near what feature?

• a mid-ocean ridge

• a subduction zone

• on an island arc

• a deep-sea trench

The preserved remains or traces of an organism that lived in the past

• fossil

• extinct

• dormant

• rift valley

Dr. Choi and his team of geologists have been studying GPS data that shows that two plates moved apart. Which diagram shows what happened between the two plates as they moved away from each other?

• Diagram A: Soft, solid rock (magma) from underneath the plates rose and hardened, adding solid rock to the edges of both plates.

• Diagram B: Sand and dirt filled in the gap that was created by the plates moving apart.

Alfred Wegner's hypothesis that the continents slowly move across Earth’s surface.

• global warming

• natural selection

• Continental Drift

• active

Which statement best describes Earth’s outer layer underneath the surface in the image?

• Underneath the soil, Earth’s outer layer is made of water.

• Underneath both the soil and the ocean, Earth’s outer layer is made of hard, solid rock.

The circular arrows inside the Earth's Mantle represent what type of motion, that drives ALL plate movement?  

• Convergent Boundary
• Ocean Currents
• Convection Currents
• Transform Boundary

Rift valleys, like the Great African Rift Valley, form as a result of:

• crustal compression.

• divergent boundaries of 2 continental plates.

• convergent boundaries

• subduction zones

Dr. Steiner and her team have been using GPS to track two plates that are moving toward each other. Which diagram shows what is happening at the place where the plates are moving toward each other?

• Diagram A: Two plates are hitting each other, and the plates are breaking into pieces, creating sand.

• Diagram C: One plate is subducting or going underneath the other plate and sinking into the soft rock below.