Geologic History
Relative Dating
Earthquakes
Mountain Building
Volcanoes
100
What is the age of Earth?
4.567 billion years old
100
The layers of sedimentary rocks get laid down in layers. What direction do they form?
horizontal
100
Before an earthquake can occur, what builds up?
Stress
100
What type of force is compression?
Compression is squeezing together
100
How is magma different from lava?
They are made of similar substances but they are located in different places. Magma is found below Earth's surface while lava is found above Earth's surface.
200
What can scientists learn from ice cores?
Ice cores can give information about the climate and precipitation of Earth from over 100,000 years ago.
200
What does the law of superposition state?
That older layers lie below younger layers if they have not been disturbed.
200
What is a break in the body of rock on Earth?
a fault
200
What type of force is shear stress?
Shear stress is tearing in opposite directions
200
What is pyroclastic material?
Clouds of ash and lava particles traveling in the air
300
What is the remains of a living organism that once lived long ago?
a fossil
300
How can crosscutting explain the age of a fault?
If a fault cuts through a layer, then the fault must be younger than the layers it cuts through.
300
Earthquakes occur on or near ___________________.
plate boundaries
300
Describe folded mountains.
They form from compression of layered rocks that lift up.
300
Which volcanoes are the mildest eruptions?
shield volcanoes
400
Name 4 different types of trace fossils.
tracks, leaf imprints, coprolite (poop), burrows, shells
400
Wooley Mammoths are the ancestors of elephants that live today according to the _________________.
The fossil record
400
Most deaths and injuries from earthquakes come from what?
Falling buildings, debris, down electrical wires, and fires
400
What type of stress causes a reverse fault?
Tension
400
What is a hot spot?
A hot spot is located over a magma plume and as the plate above moves it forms island chains.
500
Other than ice cores, what other pieces of evidence can scientists use to record changes of Earth's history?
sea floor sediments, tree rings, fossils
500
Relative dating can only give us a ________________ age of an object or event.
estimated
500
What type of energy is involved in earthquakes?
Potential energy builds up in Earth's crust and then as the Earth moves kinetic energy increases and potential energy.
500
What type of stress causes strike-slip fault?
shearing
500
What type of plate boundary is associated with a subduction zone?
Convergent
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