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Earthquakes, Pangaea, and Plates
Something for Earth Science, Mrs. Newcomb's class.
64
Science
8th Grade
02/07/2013

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Cards

Term
What are Gondwanaland and Laurentia?
Definition
Two landmasses formed when Pangaea broke apart.
Term
Why are the continents older than the seafloor?
Definition
The continental crust is less dense and does not get subducted at convergent boundaries therefore it is older.
Term
What is seafloor spreading?
Definition
The idea that new ocean floor is being created and the two plates on either side are getting further and further apart.
Term
At what type of boundaries are mid-ocean ridges found?
Definition
Divergent
Term
What is happening at divergent boundaries?
Definition
The sea floor is spreading apart and new ocean floor is being created.
Term
What are subduction zones?
Definition
Subduction zones occur when you have a collision between an oceanic crust and a continental crust. The oceanic crust is more dense and is pushed beneath the continental crust forming a trench.
Term
Why is the crust not getting larger?
Definition
Because it is being created at spreading centers BUT is being destroyed at trenches.
Term
What type of boundary occurs the St. Andreas Fault?
Definition
Strike-slip or transform.
Term
What happens at divergent boundaries?
Definition
Plates are moving apart.
Term
What happens at convergent boundaries?
Definition
Plates are moving together.
Term
What are the three types of plate boundaries?
Definition
Convergent, divergent, and transform(a.k.a. strike-slip)
Term
How does Plate Tectonics explain the movement of continents?
Definition
The crust is divided into plates which move because of convection currents in the mantle.
Term
What do we call the current theory about the movement of continents?
Definition
Plate Tectonics
Term
Why was Wegener unable to convince other scientists of his theory's validity?
Definition
He could not explain why the continents were moving.
Term
Who proposed the Theory of Continental Drift?
Definition
Alfred Wegner
Term
What did Alfred Wegner call the large land mass?
Definition
Pangaea
Term
Why did Alfred Wegner believe that the continents had moved (five reasons)?
Definition
- The shapes seem to fit together like a puzzle
- Fossils along the edge of continents seem to match
- Types of rock along coastlines seem to match
- Glacial erosional features seem to match
- Areas now cold must have been warm at some time in order for tropical organisms to have lived there.
Term
What is the place that magma leaves the Earth?
Definition
Volcano
Term
What do we call the volcano surrounding the Pacific Ocean?
Definition
Ring of Fire
Term
What is liquid rock called when it is INSIDE the Earth?
Definition
Magma
Term
How many stations must provide data to find the epicenter or an earthquake?
Definition
Three
Term
What scale is used to compare the intensity of an earthquake? (two possible answers)
Definition
Mercalli Scale / Richter Scale
Term
What is an instrument used to measure earthquake waves?
Definition
Seismograph
Term
What are the three types of earthquake waves?
Definition
P waves (primary), S waves (secondary), and surface waves.
Term
What is another name for earthquake waves?
Definition
Seismic Waves
Term
Which wave can ONLY travel through solids and gases?
Definition
S waves
Term
Which wave causes the most damage?
Definition
Surface Waves
Term
What is the point directly above the focus of an earthquake?
Definition
The epicenter
Term
What is the point under the Earth's surface where the rocks break?
Definition
Focus
Term
What causes tsunamis?
Definition
Earthquakes on the ocean floor.
Term
What type of fault is the San Andreas Fault?
Definition
Lateral or strike slip fault.
Term
What is the most common cause of earthquakes?
Definition
Faulting
Term
What is a sudden shaking of the Earth's crust?
Definition
Earthquake
Term
How were the Appalachian mountains formed?
Definition
Folding
Term
What is a downward fold?
Definition
Syncline
Term
What is an upward fold?
Definition
Anticline
Term
What do we call a bend in a rock?
Definition
Fold
Term
What is another name for a lateral fault?
Definition
Strike slip fault
Term
In which type of fault does the hanging wall move upward?
Definition
Reverse fault
Term
In which type of fault does the hanging wall move downward?
Definition
Normal Fault
Term
What is a fracture accompanied by movement?
Definition
A fault
Term
What is a word for a break in a rock?
Definition
Fracture
Term
Which type of stress twists rocks?
Definition
Shearing
Term
Which type of stress squeezes rocks?
Definition
Compression
Term
Which type of stress pulls on rocks?
Definition
Tension
Term
What are the three types of stress?
Definition
Compression, tension, and shearing.
Term
What is it called when a rock's shape, volume, or position changes?
Definition
Deformation
Term
What are forces within the Earth's crust that push, pull, or twist the crust?
Definition
Stress
Term
What type of plant and animal life occurred during the Paleozoic Era?
Definition
Seedless plants, insects, fish, amphibians, and reptiles.
Term
What type of plant and animal life occurred during the Mesozoic Era?
Definition
Gymnosperms, angiosperms, mammals, and birds.
Term
What type of plant and animal life occurred during the Cenozoic Era?
Definition
Angiosperms, and mammals.
Term
What is the Precambrian?
Definition
All the events of Earth's history that happened before the Cambrian.
Term
What is the order of the geologic time scale (starting with Eons)?
Definition
Eons, Eras, Periods, and Epochs.
Term
Australia and Antarctica are moving apart. The best explanation for this is:
Definition
There is a spreading center between them.
Term
Certain rock formation on the east coast of North America closely match formations on the west coast of Europe. This suggests what?
Definition
North America and Europe were once joined.
Term
Coal deposits have been found in Antarctica suggests that it was once nearer to the __________.
Definition
Equator
Term
The study of the movement of Earth's plates is called?
Definition
Plate Tectonics
Term
Major interactions between plates occur where on the plate?
Definition
The edges
Term
The San Andrea's fault is located on what type of boundary?
Definition
Transform Booundary
Term
Two lithospheric plates move apart at this type of boundary
Definition
Divergent Boundary
Term
Over geologic time, Earth's magnetic north pole has become the magnetic South Pole. What is this theory called?
Definition
Paleomagnitism
Term
The crust and upper part of the mantle together make up this layer where plates can be found.
Definition
Lithosphere
Term
This ex-navy captain came up with the theory he called "Seafloor Spreading"
Definition
Harry Hess
Term
Areas of frequent earthquake activity are usually near a plate boundary. Where is an exception?
Definition
New Madrid, Missouri
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