Chapter 4 Plate tectonics
Review Game

What are the 4 layers of the Earth?
Crust, mantle, inner core, outer core

The uppermost part of the mantle and crust that together forms a rigid layer is called what?
lithosphere

As the depth below the crust increases, what 2 factors also increase?
Heat and pressure

Is the inner core a solid, a liquid, or a gas?
solid

What layer of the mantle lies just below the lithosphere?
athenosphere

How does the material of the athenosphere differ from the material of the lithosphere?
Athenosphere is softer than the lithosphere

What happens in the interior of the Earth, to produce the Earth’s magnetic field?
The inner core spins faster than the outer core producing a magnetic field.

What are the three types of heat transfer?
Radiation, conduction, and convection

Describe conduction heat transfer.
When heat is transferred by the direct touching of materials.

Describe radiation heat transfer.
Transfer of energy through empty space

Describe convection heat transfer.
Heat transfer by the movement of heated fluid. Heated material is less dense than a cooler sample of the same material.
This will make the heated material rise.

What happens to convection currents when the fluid reaches a constant temperature?
Convection currents stop

What is the theory of continental drift?
All the continents were together at some point in the Earth’s past, and slowly drifted to their current positions.

Who was the scientist that proposed that theory?
Alfred Wegener

What are the 3 types of evidence Wegener used to support his theory?
Landforms, Fossils, and
Climate

Describe the evidence from landforms.
When you match up the continents on a map, points that would have been connected have the same type of landform, and the mineral deposts were the same

Describe the evidence from fossils.
When you match up the continents on a map, the fossils were the same. If the continents were not together, there is no way those animals could have crossed the ocean.

Describe the evidence from climate.
Land that is in cold climates now, has evidence that it was once located in the tropics

What is the name
Wegener gave to the super continent?
Panpaea

Why didn’t scientists accept his theory at first?
He could not explain the mechanism for the continents to move.

Explain what sea floor spreading is?
The process that continually adds new material to the ocean floor

What are the 3 forms of evidence that supports sea floor spreading?
Molten material, magnetic stripes, and drilling samples

What is the evidence from molten material?
Pillow lava and other forms of hardened lava are scattered across the ocean floor, this is evidence that molten material constantly erupts from the mid-ocean ridge

Explain the evidence from magnetic stripes.
The rocks on the ocean floor contain the direction of the Earth’s magnetic field at the time they hardened. The bands move in alternating directions as you move across the ocean.

Explain the evidence from drilling samples.
The age of the rocks near the ridge are younger than rocks that are further away from the ridge.

Explain the subduction of oceanic crust.
When oceanic crust gets pushed under another plate.

The formation, movement, and subduction of the
Earth’s plates is explained by what?
Plate tectonics

What are the 3 types of plate boundaries called?
Transform, convergent, and divergent

Explain how a transform boundary moves.
Slip past each other
↑↓

Explain how a convergent boundary moves.
Plates crash into each other
→←

Explain how a divergent boundary moves.
Plates move away from each other
←→

What is a rift valley?
A divergent boundary between 2 continental plates.

What is an ocean trench?
The location where oceanic crust dives beneath another plate

What happens when 2 continental plates converge?
Mountain building

What type of energy transformation powers plate tectonics?
Convection currents in the mantle