Chapter 25 Flashcards
What did Hess discover and name?
mid-ocean ridge
what is a long narrow depression
Rift Valley
The boundary where two plated collide is called?
Convergent plate boundary
A process where a denser plate dives beneath the continent is called?
Subduction
The boundary between two plates that are moving apart is called?
Divergent plate boundary
A type of boundary where plates slide horizontally is called?
Transform plate boundary
A sudden movement or vibration of the found that occurs when rocks slip and slide along enormous cracks in the Earth’s crusts called faults
Earthquake
A crack in the Earth’s crust is called?
Fault
The point of origin for an earthquake is called?
focus
The point on Earth’s surface directly above the focus is called?
Epicenter
When a sudden release of strain energy as a rock moves along a fault is called?
Elastic rebound
Who came up with the Continental Drift hypothesis?
Alfred Wegener
What were some pieces of evidence to support his answer?
- Coastline matched like puzzle pieces
- He looked at large land animal fossils
- Mountain ranges matched up and had similar age and rock types
What was the name of the Super Continent?
Pangaea
Who came up with the sea floor spreading hypothesis?
Harry Hess
What did he use to come up with the sea floor spreading?
Sonar
Who discovered the mid-ocean ridge
Harry Hess
Where can we find younger rock on the sea floor
Closer to the MOR
What are the types of plate boundaries
- Divergent Boundary
- Convergent Boundary
- Transform Boundary
What are the types of crust?
- Oceanic
2. Continental
How do Convergent plates move?
Towards each other
What land forms are created when Oceanic crusts and Continental crust converge?
Deep sea trench and Volcanoes
Subduction only happens with which type of plate boundary
Convergent
What type of land forms are created when two Oceanic crusts form together
Hotspots that create chain islands
What type of land forms are created when two Continental crusts form together
Mountains
How do divergent plates move?
Outwards from each other
\What are some specific examples of a divergent plate boundary
- MOR (Mid-ocean ridge)/Both are Oceanic Crust
2. East African Rift
How do transform plate boundaries move?
They slide horizontally past each other
What is a specific example for Transform boundaries?
San Andreas faults (Continental Crust)
What is a convection Current?
- Magma heats up, becomes less dense, and rises
2. Magma cools down, becomes more dense, and sinks
What other forces that help plates in motion?
Slab Pull
Ridge Push
and Friction
Which type of plate boundaries have Shallow earthquakes?
Divergent & Tranform
Which plate boundary has deep earthquakes?
Convergent plate boundaries
What are the four types of stress that can cause rocks to move?
Compression stress
Tension stress
shear stress
torsion stress
What are the types of deformation that can be caused due to stress?
Elastic
Plastic
What happens to a material when elastic deformation happens?
Deforms and snaps back to its original shape
What happens to a material when plastic deformation happens?
Deforms and remains in its new shape
How many types of seismic waves are there?
Primary waves
Secondary waves
Surface waves
Which wave is the fastest wave?
P-waves
What type of waves is a Primary wave?
A compression wave
What type of material can P-waves travel through?
Solids and liquids
What type of wave are secondary waves?
Transverse wave
What type of material can S-waves travel through?
Solids
Which wave is more complex and causes the most damage?
Surface wave
What are the two scales that help measure earthquakes?
Richter Magnitude scale Mercalli scale
What does the Richter scale measure about an earthquake?
The amount of energy released
What does the Mercalli scale measure?
The amount of damaged caused
