Chapter 25 Flashcards
a system of mountain ranges with a rift valley between them that extends around earth on the seafloor; formed where oceanic plates spread apart due to magma rising from earths mantle
mid-ocean ridge
a long narrow depression formed in between the peaks along the mid-oceanic ridge
rift valley
boundary where two plated collide, produces either subduction zones or continental collisions
convergent plate boundary
the movement of a dense oceanic plate under a buoyant continental plate
subduction
a boundary between two plates that are moving apart
divergent plate boundary
tectonic plate boundary in which plates slide horizontally past each other in opposite directions
transform plate boundary
sudden movement or vibration of the ground that occurs when rocks slip and slide along enormous cracks in Earths crust
earthquake
cracks in earths crust along which rock has moved
fault
the sudden release of strain energy from rock as it moves along a fault
elastic rebound
point of origin for an earthquake, the point from which seismic waves originate
focus
the point on earths surface directly above the focus of an earthquake
epicenter
who came up with the Continental drift hypothesis?
Alfred Weneger
what evidence did Weneger find to back up his hypotheses
- fossils (or Large animals fossils)
- Cost Lines
- Mountain and Ranges with same rock type and ages.
what is the name of the super continent
Pangaea
who came up with the seafloor spreading hypothesis
Harry Hess
How did he discover seafloor setting
he used sonar
Hess discovered what with the sonar
He discovered the mid-ocean ridge
What are the types of plate boundary
- Convergent boundaries
- Divergent boundaries
- Transform boundaries
How many transform plate boundaries are there?
1 which is the Caribbean plate
how do convergent plate boundaries move?
together, collide, or converge —->
sebduction zones only happen with which type of plate boundary
Convergent Boundary
What two types of crust that are used with plate boundary
oceanic crust and the continental crust
if we have oceanic crust and continental crust what land forms do we have?
Volcanoes
what type of land form will you have if two oceanic crust merge together
deep sea trench, or hot spots that create chain island (or volcanic island)
what type of land forms is created if two continental crust merge together
mountains
what type of crust must be present for a volcanic activity to occur
oceanic crust
how do divergent plate boundary move?
they move away from each other
what are some examples of divergent plate boundaries?
- MOR (Mid-Ocean-Ridge) (Two oceanic crust
- East African Rift
3.
how do transform plate boundary move?
They slide past each other
What is a specific example of a transform plate boundary
San Andrea Fault (Continental crust)
What is a Convection Current
- Magma heats up, becomes less dense, and rises.
2. Magma cools, becomes more dense, and sinks
What are three forces that plates in motion.
- Slab pull
- Ridge push
- Friction
which plate boundaries have shallow earthquake
divergent and transform
Which plate boundary have deep earthquake
convergent plate boundary
what are the type of stress that can act upon rocks movement
- compression stress
- tension stress
- shear stress
- torsion stress
_________ _________
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What are the two types of deformation
- Elastic
2. Plastic
What are the two types of deformation
- Elastic
2. Plastic
what happens to the material when Elastic deformation happens.
The material goes back to its original shape.
what happens to the material when Plastic deformation happens.
It takes on a new shape
how many Seismic waves are there
- Surface wave
- body wave
- Primary wave
- Compression wave
What type of Seismic waves are the fastest
Primary waves (P-waves)
What type of wave is a primary wave
Compression wave
What type of material can primary wave move through
Solids and liquids.
What type of wave is a S-wave
transverse wave
What type of materials can the S-wave pass through
Solids
Which waves is the most complex and does more damage.
Surface wave
What are the two scales that help measure earthquakes
- The Richter scale
2. Mercalli
What does the Richter scale measure about an earthquake
the amount of energy
What does the Mercalli scale measure about the earthquake.
which is the amount of visible damage.
