earthquakes
What scale measures the strength of an earthquake??
moment magnitude sclae
What is a volcano?
Anything that shoots out lava from the ground
What are the three plate boundaries?
divergent, convergent and transform
Where does seafloor spreading occur
mid ocean ridges
What was the supercontinent called?
Pangaea
Where do earthquakes occur?
Usually at plate boundaries, especially at transform
Where are most volcanoes located on a map?
the ring of fire
What are three pieces of evidence alfred wegener used to try and prove his theory of continental drift?
fossils, puzzle pieces and mineral deposits
What piece of technology allowed us to map the ocean floors and find the mid ocean ridges?
SONAR
About how fast do the tectonic plates move??
1-2 cm a year
what is the center of an earthquake?
the hypocenter
Where do volcanoes occur or are made at?
at plate boundaries
What is the theory of continental drift and tectonic plates??
The idea that the continent are moving slowly based off the tectonic plates or crust moving do to the convection in the mantle below the crust.
Where is the rock youngest?
at a mid-ocean ridge.
What tool measures the vibrations caused by an earthquake??
seismograph
What is above the hypocenter at the surface?
The epicenter
What are the 4 types of volcanos
caldera, composite, shield and cinder cone
What landforms and events can happen at plate tectonic boundaries? Atleast 5
tectonic plates cause mountains, ridges, volcanoes, earthquakes, tsunamis, valleys
Which rock is older: continental or oceanic
continental, does not subduct
Why are volcanoes important?
They let us look at earth's layers
What is the difference in strength and energy of a earthquake measured a 5 and another measured a 7
it is 100x times stronger and 1089x more energy
How does a hot spot create a chain of islands??
The crust moves but the spot in the mantle where the magma shoot up does not. so everytime it erupts the island above has moved slightly
What are the three types of stresses that can be placed on rocks at the boundaries and the faults that go with them
strike slip - shearing
normal - tension
reverse - compression
Where would you find the oldest rocks in oceanic crust??
subduction zone
Why does the ocean plate subduct at a convergent boundary?
it weighs more and is more dense