Harnessing Human Energy

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

• Underneath both the soil and the ocean, Earth’s outer layer is made of sand and water.

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

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

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

Dr. Raisa and her 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: A new plate from underneath filled in the gap that was created by the plates moving apart.

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

• Diagram C: Ocean water filled in the gap that was created by the plates moving apart.

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

Fossil remains of Lystrosaurus (an extinct four-legged animal) have been discovered in India and South Africa. When they were living, all the Lystrosaurus lived together on land, and they could not swim. However, now there is an ocean between the Lystrosaurus fossils. What could explain how these fossils got so far apart?

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

• India and South Africa are parts of different plates. The plates floated away from each other across the ocean.

• India and South Africa 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 South Africa are parts of different plates. The plates were sometimes pushed far apart by earthquakes, and soft, solid rock from underneath got added to the edges of the plates.

Scientists often study cross sections to better understand what the inside of something looks like. If we took a cross section of a potted plant by cutting it vertically, what would the cross section look like?

• Diagram A

• Diagram B

• Diagram C

• Diagram D

A team of geologists wants to study hard, solid rock under the surface of Earth. The team is considering drilling down in Saudi Arabia (1) or in the Arabian Sea (2). Where will the geologists find hard, solid rock?

• neither under 1 nor 2, because there is sand and gravel under both places

• neither under 1 nor 2, because there is water under both places

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

• only under 1, because Earth’s outer layer is made of hard, solid rock under continents but not under the ocean

Dr. Patel 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 B: Two plates are pushing against each other, causing the edges to bend upward.

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

• Diagram D: One plate is going underneath the other plate and sinking into the ocean below.

Similar rock formations have been discovered in Brazil and South Africa. These rock formations were formed at the same time and are made of the same types of rocks. What could explain how these rocks got so far apart?

• Brazil and South Africa are parts of different plates. The plates were sometimes pushed far apart by earthquakes, and soft, solid rock from underneath got added to the edges of the plates.

• Brazil and South Africa are parts of different plates. The plates floated away from each other across the ocean.

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

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

Patterns on this map tell us that . . .

• volcanic activity and earthquakes can cause damage to buildings and hurt people.

• volcanic activity and earthquakes happened in similar areas.

• volcanic activity and earthquakes happened in random locations all over the map.

• volcanic activity and earthquakes happened in the following order: volcanic activity, earthquake, volcanic activity, earthquake, and so on.

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

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

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

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

• Underneath both the soil and the ocean, Earth’s outer layer is made of sand and water.

Dr. Bailey and his team are studying two plates that are far apart from each other. However, these two plates used to be next to each other. Which diagram shows what Dr. Bailey and his team would find between these plates?

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

• Diagram B: A new plate from underneath filled in the gap that was created by the plates moving apart.

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

• Diagram D: Ocean water filled in the gap that was created by the plates moving apart.