Download DCA-geoscience-exam-3-study-guide-key

Name ________________________
Date/Hour __________
Science District Common Assessment #3 Study Guide
Earth's Interior
1. The interior of the Earth can be mapped using
__seismic_______ waves.
2. Seismic waves travel through Earth's layers at different
speeds depending upon the ___density_________ and
composition within the Earth.
3. The fastest traveling seismic wave is a
____primary_______ wave.
4. Using the graph on page 535, the difference in arrival times
between a P-wave and a S-wave 3000 km from the epicenter
is ____4.5min_______.
5. When an oceanic plate collides with a continental plate, the
oceanic plate is subducted because _____Oceanic crust is
denser than continental crust________________.
6. The location of most earthquakes occur in narrow bands
which corresponds with which type of tectonic plate
boundary? ___ continental -continental____(subducting
tectonic plates)__
7. Why does California experience more earthquakes than we
do in Michigan? ____California is located on the boundary
of two crustal plats, but we are not.________
8. A string of volcanoes usually indicates ____plate
boundaries________.
9. Volcanoes are characterized by differences in ___size and
shape____ and composition.
10. Earthquakes are detected, measured, and recorded by
instruments called _seismographs___.
11. The Richter scale measures which earthquake
characteristic? __magnitude___.
12. Describe how a volcanic eruption could change the Earth's
climate. Ash blocks sunlight, causing temperatures to drop
13. What causes new crust to form at mid-ocean ridges?
___seafloor spreading
14. The Himalayan Mountains are still increasing in height
because two ____tectonic____ plates are colliding.
15. Tectonic Plates move because of mantle _convection___ and
the force of __gravity_____.
16. Scientists use GPS to map the rate of tectonic plate
movement and have discovered that the Earth's tectonic
plates move an average of _1-12cm_____ per year.
17. What 2 processes can transform igneous rock into
sedimentary rock? erosion, and sedimentation.
18. What 2 processes can transform sedimentary rock into
igneous rock? ____________melting and cooling_______
19. All igneous rocks begin as __magma____.
20. Heat and pressure inside the Earth's crust change rocks
through this process which is called metamorphism____.
21. Which type of crust, continental or oceanic, is younger,
thinner, and denser? oceanic crust
22. Most of the injuries and deaths due to earthquakes are
caused by movement of the ground_____.
23. This forms when tectonic plates collide. rift valley___
24. ____subducting_ oceanic lithosphere pulls the rest of the
plate along with it.
25. Explain how rock is recycled in subduction zones. ___rock is
recycled as it is pulled back into the mantle of the Earth as
subduction zones_
26. The greatest risk to humans caused by underwater
earthquakes is a __tsunami____.
27. Oceanic plates always go under continental plates because
they are __denser___ then the continental plates.
28. Are continental crusts older or younger than oceanic
crusts? _older____
29. Are continental crusts denser or less dense than oceanic
crusts? ____less dense_______
30. Which is thicker, continental crust or oceanic crust?
_____continental____
31. How does the temperature of continental and oceanic crust
compare? ________They are similar__________
32. What type of rock is obsidian? _____obsidian__________
33. Why was the continental drift theory not originally
accepted? __Wegener couldn't explain why or how
continents moved._
34. How is Earth's atmosphere today different than it was 4.5
billion years ago? _________Has more oxgen now
(cyanobacteria) ____________
35. Which 2 layers of Earth are solid? ____crust and inner
core_________
36. Earth's magnetic field is created by ____The flow of
molten iron in the outer core____.