Earth's Layers
The rigid outer layer of Earth, composed of the crust and upper mantle.
What is the lithosphere?
When plates pull apart, creating new crust, like at mid-ocean ridges.
What is a divergent boundary?
The supercontinent that existed roughly 300 million years ago.
What is Pangea?
These underwater mountain ranges form at divergent boundaries.
What are mid-ocean ridges?
This is the number of recognized oceans in the world.
What is five?
The semi-fluid layer of the mantle beneath the lithosphere where convection currents occur.
What is the asthenosphere?
Where two plates collide, causing subduction or mountains.
What is a convergent boundary?
The theory that Earth's continents have moved over geological time.
What is continental drift?
Deep valleys that form on land when continents pull apart, like the East African Rift.
What are rift valleys?
There are this many continents.
What is seven continents?
This layer's convection currents are the driving force behind plate movement.
What is the mantle?
Two plates slide horizontally past each other, causing earthquakes.
What is a transform boundary?
The process where oceanic crust sinks beneath another plate at convergent boundaries.
What is subduction?
The world's largest tectonic plate, mostly beneath the Pacific Ocean.
What is the Pacific Plate?
The South American wonder, Machu Picchu, is located in this country.
What is Peru?
The innermost layer, primarily iron and nickel, with a solid inner part and liquid outer part.
What is the core?
At this type of boundary, an oceanic plate sinks beneath a continental or another oceanic plate.
What is a subduction zone?
The speed at which plates move, often compared to fingernail growth.
What is centimeters?
Chains of islands (like Japan) form where two oceanic plates converge.
What are volcanic island arcs?
The world's longest river, flowing through northeastern Africa.
What is the Nile River?
There are islands surrounding Australia they are called.
What is Oceania?