2.1.0 What Are Tectonic Plates? Our Earth and Its Movements

Match the following components of our planet with the description of their proportion.

• Covers a vast area of Earth's surface but is shallow compared to other layers

• The mantle

• Makes up only a tiny fraction of our planet

• The oceans

• Comprises a substantial, dense section at the center of Earth

• The core

• Makes up a significant portion but not the largest of Earth's volume

• The crust

What is the Earth's outer layer called? (a)  

• The atmosphere

• The core

• The lithosphere

• The mantle

Answer explanation

The Earth's outer layer is called the lithosphere, which includes the crust and upper part of the mantle.

What are the two main parts of the Earth's core?

• The lithosphere and asthenosphere

• The outer and inner core

• The crust and the mantle

• The upper and lower mantle

Answer explanation

The two main parts of the Earth's core are the outer core and inner core, as stated in the correct answer choice.

The hottest part of the Earth is (a)   .

• The mantle

• The crust

• The outer core

• The inner core

Answer explanation

The inner core is the hottest part of the Earth due to immense pressure and heat, reaching temperatures up to 5700°C.

What concept explains the movement of Earth's tectonic plates?

• Magnetic field

• Solar radiation

• Gravity

• Plate tectonics

Answer explanation

Plate tectonics is the concept that explains the movement of Earth's tectonic plates, not magnetic field, solar radiation, or gravity.

What was the supercontinent called that existed 335 million years ago?

• Gondwana

• Eurasia

• Pangaea

• Laurasia

Answer explanation

The supercontinent that existed 335 million years ago was called Pangaea, making it the correct choice among the options provided.

What type of plate margin forms when two plates move away from each other?

• Destructive

• Convergent

• Constructive

• Conservative

Answer explanation

When two plates move away from each other, a constructive plate margin is formed where new crust is created as magma rises to fill the gap.

What geological feature is formed at a constructive plate margin?

• Mountains

• Islands

• Trenches

• Volcanoes

Answer explanation

At a constructive plate margin, volcanoes are formed due to the upwelling of magma from the mantle, creating new crust as lava solidifies.

What causes the tectonic plates to move?

• Tidal forces

• The rotation of the Earth

• Convection currents in the mantle

• Wind erosion

Answer explanation

Convection currents in the mantle cause the tectonic plates to move by transferring heat and creating movement in the Earth's crust.

Which of the following is an example of a conservative plate margin?

• The Mariana Trench

• The San Andreas Fault

• The Mid-Atlantic Ridge

• The Himalayas

Answer explanation

The San Andreas Fault is an example of a conservative plate margin where tectonic plates slide past each other horizontally.