Earths Interior Flashcards
What is the crust made of?
Oxygen, silicone, aluminum, and iron
The outer layer of the earth is called?
Crust
What is beneath the crust?
The mantle
What are the two different types of the mantle?
outer and inner layers
What is the layer of cool, rigid rock in the uppermost layer of the mantle?
Lithosphere
The inner layer beneath the lithosphere in the mantle is called?
Asthenosphere
What is the strongest part of the lower mantle beneath the asthenosphere?
mesosphere
What is denser than the mantle?
Core
Describe the core in three ways
Temp reaches 7000 C
Large sphere of metal that occupies the earth’s center
Made mostly of iron
What are the two types of the core?
Outer and inner core
How deep is the outer core and what is it?
2260 km
So hot it is a liquid
How deep is the inner core and what is it?
1220 km
It is a solid
What is the continental drift?
When the continents move slowly across the earth’s surface
What did Wegener hypothesize?
That the continents were once joined in a single supercontinent called a Pangaea. It broke into pieces and moved apart.
What is sea-floor spreading?
When the pieces of the ocean floor move apart on each side of the crack, magma fills in the gap forming new crust.
What is subduction?
As the sea floor spreading occurs, old oceanic plates sink into the mantle
What is a trench?
As a plates sinks, it bends, forming a large groove in the ocean floor
What does sea floor spreading create?
New crust at mid ocean ridges.
What is the chain of underwater mountains along the floor of the Atlantic Ocean are called?
Mid-Atlantic Ridge
What was the major evidence used to support Wegner’s theory of continental drift?
Sea floor spreading
What causes the plates to move?
Convection current under the lithosphere
What is convection current?
The cores heat energy is transferred to the inner layer causing it to rise towards the earth’s surface.
It then cools and sinks as the heated mantle transfers into heat energy to the the lithosphere.
