Unit 3 plate tectonics
What were Alfred Wegener's 4 pieces of evidence to support his theory of continental drift?
1. Perfect fit of continents 2. Fossils correlation 3. Rock Mountain correlation 4. Past Climate Data
What is the minimum number of seismic stations needed to determine the epicenter of an Earthquake?
3
Describe s waves and how they move?
S waves (second waves) move only through solids. Travel slower than P waves (primary waves)
The process by which new ocean lithosphere forms at mid-ocean ridge...
Sea Flooring
Which statement is true about P/S waves
Shear waves travel slower than Compressional Waves
This plate movement occurs when one plate moves under another plate.
Subduction
The Marinas Trench near Japan is the result of which plate boundary?
Subduction Boundary
What can be done to minimize death and/or destruction in an earthquake prone area?
Lessen the population, Have less tall building built, and Build with better enforcement for building.
Which is used to measure Earthquakes?
Mercalli Scale, Moment Magnitude, and Ritcher Scale
This feature occurs when two continental plates collide with one another
Mountain Range
Which Seismic wave is most destructive?
Surface Wave
Describes what happen at a convergent when an oceanic plate and continental plates are colliding?
Oceanic Crust is destroyed and new Continental Crust is created
An Earthquake epicenter is
On the surface directly above the focus
Why is it important to have data from three different locations to determine where the epicenter of an earthquake is?
One seismograph tells you nothing. Two seismographs are ambiguous. Three is the absolute minimum needed to triangulate, assuming accurately synchronized arrival times of the shock waves.
Which layer are S waves and NOT able to travel through
Outer core
What are the two abundant elements found within the earth's crust
Oxygen and Iron and aluminium, and silicon
Describes p waves and how they move.
P waves (primary wave) move through all states of matter. Travel faster then s waves (secondary wave).
The large land mass that Alfred Wegner proposed
Pangaea
The theory that earth is divided into moving plates
Plate Tectonic
Focus
Point at the depth where the rocks ruptured to produce earthquakes; place where quake waves originate
P waves
Primary waves. Can go through solids and liquids.
What is continental crust mostly made of, what is oceanic crust mostly made of? How does this affect their density?
The continental crust is made of granitic. The Oceanic crust is made of basalt. Effects the weight of the crust.
When the dozen or so plates on the Earth's crust they create land forms (True or False)
True
S waves
secondary waves. Can only go through solids
Which waves causes the most damage
seismic wave
Surface Waves
seismic waves that travel along the Earth's surface. Are most destructive waves.
Crust
the layer that we live on and is the most widely studied and understood
outer core
the metal are in all liquid state
Epicenter
the point on the Earth's surface directly above the focus of an earthquake
Pangaea
the super continent where all the continents were once joined.
What causes earthquakes?
transform plates move past each other and caused by a sudden slip on a fault.
This plate movement occurs when two plates move apart
Divergent Boundary
What is a hot spot? How do they create chain of islands?
A hot spot is are volcanic regions thought to be fed by underlying mantle that is extremely hot compared with the surrounding mantle. They create chains of islands by volcanoes eruption
Divergent Boundary
A plate boundary where two plates move away from each other.
Transform Boundary
A plate boundary where two plates move past each other in opposite directions
Convergent Boundary
A plate boundary where two plates move toward each other.
Hot spot
An area where magma from deep within the mantle melts through the crust above it
Mid-Ocean Ridge
An undersea mountain chain where new ocean floor is produced; a divergent plate boundary.
The lithosphere is the crust and the upper most part of the mantle, it floats on the...
Asthenosphere
What type of boundary is crust destroyed?
At a Convergent boundary
At what type of boundary is new crust created
At a Convergent boundary crust is considered new
Describe what happens at a transform boundary
At a transform boundary the plates slide past eachother and causes faults in the earths crust and sometimes causes earthquake.
The oceanic crust is mostly made of (blank)
Basaltic Rock
Similar fossils found on different continents is evidence for....
Continental Drift
The hypothesis that states the continents were once a large mass that broke apart.
Continental Drift
The theory that states the continents were once formed a super continents called Pangaea
Continental Drift
Plate movement is thought to be caused by
Convection Currents
The Himalayas were formed when by type of plate boundary?
Convergent Boundary
Describe what happens at a divergent boundary when two oceanic plates are spreading apart.
Creates mid ocean ridge
Describe what happens at a divergent boundary where two continental boundary are spreading apart.
Creates rift valley
Which interior layer are P waves able to travel through
Crust, Mantle, inner and outer core
Warm Magma rises while cooler magma sinks because of difference in...
Density
The MOR (mid oceanic ridge) is an example of what type of plate boundary?
Divergent Boundary
Describe 3 things to minimize death and destruction in an earthquake prone area
Having buildings be appropriately made with the right material for the occasion, more sturdy gas poles and electric poles, and then building houses with appropriate material
The Hawaiian formed over a (blank)
Hot Spot
Continental Drift
The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations
What are the layers of the earth from outside-in? Where is the lithosphere located?
The layers from the outside to the inside are the crust, mantle, outer core, and inner core. The lithosphere is located in the crust and the upper part of the mantle.
What does magnetosphere protect us from? How does this create Aurora Borealis (northern lights)?
The magnetosphere saves us from solar and cosmic radiation. Creates the northern lights by the magnetic field and collides with gas atoms causing the atoms to give off lights
The San Andreas Fault in California is the result of what plate boundary?
Transform
The plate movement occurs when two plates slide past one another
Transform Boundary
Plate Tectonics explains how forces below the earths surface have shaped our land forms (True or False)
True
Tectonic plates move in different directions and at different speeds (True or False)
True
Tsunami
Underground Earthquake
What are the steps using the wedge method to find the distance to an earthquakes epicenter?
Using your compass, draw a circle with a radius equal to the number you came up with in Step #2 (the radius is the distance from the center of a circle to its edge). The center of the circle will be the location of your seismograph. The epicenter of the earthquake is somewhere on the edge of that circle.
Why do earthquakes often caused damaging fires?
Vibrations can cause gas and power lines to break
What forms when 2 oceanic plates collide
Volcanic Islands
Where are earthquakes and volcanoes on earth found. What is this location specifically called?
Volcanoes and Earthquakes are commonly found Destructive Plate Boundaries or constructive plate boundaries.
What force changes land form?
Weathering, Erosion, and Humans
What causes erosion ( The movement of sediment from one location to another)?
Wind, Ice, and Wind
The oceanic crust is (blank) compared to the continental crust.
Younger
Volcanic Arc
a chain of volcanic mountains formed at an ocean-continental convergent boundary
Fault
a crack in the earth's crust resulting from the displacement of one side with respect to the other
Rift
a split, break, breach
Earthquake
a sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action.
Alfred Wegener
came up with the theory of continental drift
Trench
extremely deep areas in the ocean that are created by a subducting plate
Describe what happens at a convergent boundary when two continental plates are colliding?
forms mountain ranges
what two elements found within the cores?
iron and nickle
Mantle
is much hotter and has the ability to flow
inner core
metals are squeezed together. are forced to vibrate in place like a solid.
