Download 220_11Prelim 1 - Earth and Atmospheric Sciences

EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
Name ______________________
Part I. Fill in the blank with a word or a phrase. 1 point per answer.
1. In the Big Bang, the only chemical elements that were synthesized were ______,
_______ and a small amount of Li.
2. Primitive meteorites, that is those that are thought to preserve material from the solar
nebula and therefore tell us about the early stages of solar system formation, are all of
the class called ____________________, in reference to the small spherical droplets
they contain.
3. Give an example of a carbonate mineral _______________________ .
4. How do we know that the Earth’s outer core is liquid? __________________________
___________________________________________________________________ .
5. In micas, the silica tetrahedra are organized into _____________________.
6. __________________ is an example of a mineral that is actually a solid solution, in
which ____________ may substitute for ________________ and vice versa.
7. Name two properties of water that make it a highly unusual substance:
__________________________________________________________________
__________________________________________________________________
8. The four terrestrial planets are ___________, ______________, _______________
and Earth.
9. The two sources of heat and energy in the Earth’s interior are
____________________, and ____________________________.
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
10. The velocity of seismic waves varies as the square root of the ratio of the elastic
modulus to ________________ .
11. In the spaces provided below, write the name of the appropriate metamorphic facies.
(This question is worth 5 points – you get full credit if you correctly list just 5 facies).
12. The Earth’s moment of inertia has been determined from the rate of precession of its
rotation axis. The moment of inertia turns out to be less than it would be if the Earth
were a sphere of uniform density. What does that tell us about the Earth?
___________________________________________________________________ .
13. The age of the Earth is approximately ______________________________ years.
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
14. The outermost part of the Earth that forms a thermal boundary layer and behaves
rigidly is known as the __________________________________ .
15. A depression in the Earth that forms when the roof of a magma chamber collapses
following a volcanic eruption is known as a ____________________ .
16. Compressive forces typically result in _________________ faults, which are most
common at ________________ plate boundaries.
17. What can you determine about an earthquake from the difference in arrival times of pand s-waves at recording station (i.e., a seismograph)? ________________
_______________________________________________________________.
18. The Rayleigh Number of the Earth’s mantle has been estimated to be 108. What can
we conclude from this? ________________________________________________
_______________________________________________.
19. When strain is elastic, it is linearly proportional to _______________ . Furthermore,
the strain is __________________________ .
20. A metamorphic _____________ is a set of metamorphic mineral assemblages, each
for a specific rock composition, that form over a specific range of pressure and
temperature.
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
21. On the folds below, label the anticlines (antiforms) and synclines (synforms).
22. Newton predicted that form of the Earth would be an oblate spheroid rather than a
sphere. Why? ______________________________________________________
__________________________________________________________________
23. The gravitational equipotential surface of the Earth; i.e., the radial distance at which the
force of gravity is the same, differs slightly from an oblate spheroid. The name of this
surface is the ______________________.
24. What other planetary bodies in our solar system have an oxygen-rich atmosphere?
__________________________________________
25. What is the key difference between amorphous solids and liquids on the one hand and
a crystalline solid on the other?
___________________________________________________________________
___________________________________________________________________
26. The mineral with the chemical formula Fe3O4 is called _________________________.
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
27. The compass direction that the trace of a fault makes on a map is known as the
_____________________ ; the angle that the plane of the fault makes to horizontal is
known as the _______________.
28. A light-colored, fine-grained, relatively silica-rich igneous rock containing the minerals
alkali feldspar, biotite, and quartz is known as a _______________ .
29. An igneous rock having the same composition and mineralogy and the one in the
question above, but with a coarse grain size would be known as a ________________.
30. A foliated, but not banded, metamorphic rock rich in sheet silicates such as mica,
whose individual crystals are large enough to make out with the naked eye would be
called a _________________ .
31. The temperature at which a multiphase substance begins to melt is known as the
____________________ .
32. The energy required to melt a specific mass (e.g., 1g) of a substance is known as its
____________________________________________ .
Part II Answer with a sketch, drawing or a few sentences.
33. What causes the melting the produces the volcanoes in subduction zones? (2 points)
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
34. Sketch the silicon tetrahedron, showing the relative positions of the silicon and oxygen
atoms. (8 points)
35. Explain why volcanoes that form over mantle plumes are analogous to cumulus clouds
(10 points)
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
36. The Ocean Drilling Program (ODP) was initiated as a test of plate tectonic theory.
What predictions of the theory about the ocean floor was ODP designed to test? What
was the outcome? (8 points)
37. The solid Earth consists of 3 distinct layers: the crust, mantle and core. Why does this
layered structure exist? When did these layers form? Did the crust and core form
immediately when the Earth formed, or did they form later? Did the crust and core
form at the same time? (6 pts)
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EAS 2200
Spring 2011
Introduction to the Earth System
Prelim Exam 1
38. Describe the difference between seismic p- and s-waves. In particular, describe the
difference in motion these waves induce in the material through which they travel.
Which wave travels more rapidly? (8 points)
39. Describe how the pattern of magnetic anomalies parallel to mid-ocean ridges can be
accounted for by sea-floor spreading. Use sketches if you wish. (10 points)
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