Earthquakes- Plate Tectonics Flashcards
(40 cards)
What is continental drift?
Where continents are always in motion
Who hypothesized continental drift?
Alfred Wegener
What was the name of the super continent?
Pangea
What are 3 evidences of continental drift?
Climate change, fossils, and land features
What is sea-floor spreading?
The process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge
What are the mountain ranges in the middle of the ocean called?
Mid-ocean ridge
The sea-floor moves like what?
Does it carry the continents along with it?
The sea-floor moves like a conveyor belt. It DOES takes the continents with it
What are 3 evidences of sea-floor spreading?
Magnetic stripes, samples, and molten material
What are plate tectonics?
Rigid slabs of rock that move with respect to each other
What type of current is behind plate tectonics?
Convection currents
What are the 3 types of plate boundaries?
Convergent- 2 plates collide
Divergent- Plates move apart
Transform- Plates slide past each other
What are 3 types of stress?
Compression, tension, and shearing
Name 2 landforms caused by compression.
Mountain ranges, ocean trenches
What is the difference between plastic and elastic strain?
Plastic strain makes a permanent change in the shape of a rock
Name the 3 types of faults.
Normal, reverse, and strike-slip
Describe each fault line.
(You can draw on the test)
I think we all wanna draw
What is the focus?
The point beneath the earth’s surface where rocks under stress breaks to cause an earthquake
What is the epicenter?
The point on the surface directly above the focus
Name 3 types of seismic waves.
Primary (P waves), Secondary (S waves), and Surface waves
Which seismic wave is seen first?
Primary waves (P waves)
Which seismic wave somes 2nd after lag?
Secondary waves (S waves)
Which seismic wave causes ground movement?
Surface waves
How do you find the epicenter of an earthquake?
Triangulating data
What device measures seismic activity?
Seismometer
