Ch 25 Flashcards
Mid-Ocean Ridge
Hess discovered a system of mountains ranges on the seafloor separated by valleys
Rift Valley
A long, narrow depression
Convergent Plate Boundary
The boundary where two plates collide
Subduction
When a denser plate dives beneath a less dense plate
Divergent Plate Boundary
Two plates move along a mid-ocean ridge.
Two moving plates apart
Transform Plate Boundary
Plates slide horizontally past each other in the opposite direction
Earthquake
when tectonic plates move in the Earths crust
Fault
responsibility for an accident or misfortune
Elastic Rebound
what happens to the crustal material on either side of a fault during an earthquake
Focus
the center of interest or activity
Epicenter
the point on the Earth’s surface directly above a hypocenter or focus
Who came up with the Continental Drift hypothesis.
Alfred Wegener
what were some evidence that Wegener used to support his hypothesis
- Fossils(Large Land Animals Fossils)
- Coast Line( matched up like puzzle pieces)
- Mountain Ranges( matched up with same rock type and ages)
What was the name of the Super Continent
Pangia
Who came up with the Sea Floor Hypothesis
Harry Hess
How did he discover Seafloor Spreading Hypothesis
Sonar
What are the three types of plate boundaries
Divergent boundary, Convergent boundary, Transform boundary
subduction zones only happen with what type that boundaries
convergent plate boundaries
How do Divergent Plate Boundary’s move?
They divide( They move apart)
What are some examples of Divergent Plate Boundarys
- Mid Ocean Ridge(Oceanic Crust)
2. East African Rift( 2 Continental Crust)
How do Transform Plate boundary’s move
Slide past each other
what is a example of a transform Boundary
San Andres Fault ( Continental Crust )
What is a Convection Current
- Magma heats up, becomes less dense and rises
2. Magma cools down and gets dense, then sinks down
What plate boundary has shallow earthquakes
Divergent and Transform
Which plate boundary has deep earthquakes
Convergent
What type of stress that acts upon rock moment
- compression stress
- a tension stress
- a sheer stress
- torsion stress
What are the two types of deformation
- Elastic
2. Plastic
What happens to the rock or the material when elastic deformation happens
The material goes back to its original shape
What happens to the rock or the material when plastic deformation happens
It takes on a new shape
How many types of seismic waves are there
- Primary
- Secondary
- Surface
What type of seismic Wave is the fastest
P-Waves
What type of wave is a primary wave
It’s a compression wave
What type of materials can P-wave pass through
- Solids
2. Liquids
What type of wave is an s-wave
Transverse
What type of materials can an s-wave pass through
- Solids
Which wave is the most does the most damage
Surface waves
What are the two scales help measure earthquakes
- Richter Scale
2. Mercalli Scale
What does the Richter scale measure in a earthquake
The amount of energy
What does the Mercalli scale measure
The amount of measurable damage
