GS1100
Principles of Geology (section 2)
2007 Fall Mid-Term Test
Make sure you have
marked your name and student ID correctly on the provided answer sheet. Turn in
your answer sheet to your Lab TA when you are done for him to check your name
and ID number. Note that the
choices A, B, C, D in the question sheet correspond to 1, 2, 3, 4 on the answer
sheet. Be careful not to mark “
Multiple Choices (chose the correct or
the best answer)
1.
Which of the following best defines a mineral and a rock?
A) A rock has an orderly, repetitive,
geometrical, internal arrangement of minerals; a mineral is a lithified or
consolidated aggregate of rocks.
B) A mineral consists of its constituent
atoms arranged in a geometrically repetitive structure; in a rock, the atoms
are randomly bonded without any geometric pattern.
C)
In a mineral the constituent atoms are bonded in a regular, repetitive,
internal structure; a rock is a lithified or consolidated aggregate of
different mineral grains.
D) A rock consists of atoms bonded in a
regular, geometrically predictable arrangement; a mineral is a consolidated
aggregate of different rock particles.
2.
Which of the following is not a mineral?
A)
olivine B) limestone C)
calcite D)
quartz
3.
Which geologic concept is described by "the present is the key to the
past"?
A)
biblical prophesy B) uniformitarianism C)
Aristotelian logic D)
catastrophism
4.
The average thickness of the continental crust is about
A) 35-40 km B)
100-200 km C)
1000-2000 km D)
5-10 km
5.
In correct order from the center outward, Earth includes which layers?
A)
core, inner mantle, outer mantle, crust B) inner core, outer core, mantle, crust
C)
inner core, crust, mantle, hydrosphere D)
core, crust, mantle, hydrosphere
6.
The tectonic plates
A) are the
outermost shell of the solid Earth. B)
are a rigid, solid layer about 100 km thick
C) includes the
crust and the uppermost mantle D) all of the above
7.
At mid-ocean ridges, two plates are
A)
moving towards each other. B) moving away from each other.
C)
sliding along each other. D)
stationary.
8. According to Plate Tectonics theory, most active volcanoes occur
A) on continents. B) in large tectonic plates.
C)
along plate boundaries. D) randomly over continents.
9. What are the two most abundant elements
in the Earth’s crust?
A)
iron and magnesium B) oxygen and silicon
C)
nitrogen and oxygen D)
silicon and calcium
10. Atoms of the same
element (oxygen, for example) have the same number of __________.
A) electrons in the nucleus B) protons in the nucleus
C) neutrons in the outer nuclear shell D) electrons in the valence bond level
11. In table salt (NaCl), sodium and chlorine atoms bond by
A) sharing the electrons in their outer shells.
B) transferring
an electron in the outer shell of the sodium atom to the outer shell of the
chlorine atom.
C) having valence electrons freely migrating among the ions of sodium and chlorine.
D) all above.
12. What mineral is the
hardest known substance in nature?
A) graphite B) native gold C) diamond D) muscovite
13. Why
is basalt finer grained than gabbro?
A) gabbro formed from quick cooling of
magma.
B) basalt
formed from quick cooling of magma.
C) basalt has a mafic composition.
D) gabbro has a mafic composition.
14. Visible quartz and potassium feldspar grains are the main
constituents in a ____________.
A)
granite B) gabbro C) basalt D) rhyolite
15. Which of the following minerals would crystallize
early from a cooling
silicate magma?
A) biotite B) quartz C) olivine D) muscovite
16. Magma
generation in subduction zones are mainly caused by
A) releasing of water and volatiles from the
subducting plate
B) pressure
release in the subducting plate
C) temperature
increase in the surrounding mantle
D) all above
17. Which of the following tend to increase the explosive potential of a magma body beneath a
volcano.
A)
High viscosity and dissolved gas
B) High viscosity; low dissolved gas
content
C) Low silica content, low viscosity
D) Low viscosity; low dissolved gas
content
18. Eruptions dominated by basaltic lava flows typically form what type of volcanoes?
A) composite B) stratospheric
C) cinder cone D) shield
19. Why do magmas rise toward Earth's surface?
A) Magmas are more viscous than solid
rocks in the crust and upper mantle.
B) Most magmas are richer in silica than
most crustal and upper mantle rocks.
C)
Magmas, being melts and having gases, are less dense than the adjacent solid rock.
D) magmas have higher content of pyroxenes than
the surrounding rocks.
20. Which of the following is NOT a process of physical (mechanical) weathering?
A) Frost wedging
B) unloading
C) thermal expansion
D) dissolution
21.
Which of the following silicate minerals are most resistant to chemical
weathering?
A) quartz B)
olivine C)
hornblende D)
potassium feldspar
22. In
the soil profile, the A horizon
A) is located below the O horizon B) is called the zone of leaching
C) is part of the “top soil” D) all above
23. What is probably the
single most important, original, depositional feature in sedimentary rocks?
A) sizes of the sand grains
B) degree of lithification
C)
bedding or stratification
D) compaction of the mud and clay
24. What is the main
difference between a conglomerate and a sedimentary breccia?
A)
Breccia clasts are angular; conglomerate clasts are rounded.
B) A breccia is well stratified; a
conglomerate is poorly stratified.
C) Breccia clasts are the size of
baseballs; conglomerate clasts are larger.
D) Breccia has a compacted, clay-rich
matrix; conglomerate has no matrix.
25. Detrital sedimentary
rocks are classified (named) based on the _________
A) colors of the cementing minerals
B)
grain sizes of the detrital particles
C) compositions of soluble minerals
D) degree of compaction and lithification
26.
A)
quartz; (SiO2) B) hematite (Fe2O3)
C) halite (NaCl) D) calcite (CaCO3)
27. Which of
the following is the most common type of chemical
sedimentary rock.
A)
Limestone B) Chert
C) Phosphate rock D) Quartz sandstone
28. Which of
following sedimentary rocks indicate long-distance transportation of the
sediements?
A) quartz sandstone
B) breccia
C) arkose
(sandstone with lots of feldspar particles)
D) none of above
29. Which of the following
forms at the highest grade of regional metamorphism?
A) gneiss B) schist
C) slate D) phyllite
30. What major change
occurs during metamorphism of limestone to marble?
A)
calcite grains recrystallize to larger and interlocked grains.
B) clays crystallize to micas, forming a
highly foliated, mica-rich rock
C) limestone grains react to form quartz
and feldspars
D) calcite grains are dissolved away leaving
only marble crystals
31. What type of foliation results from the parallel alignment of
abundant, coarse-grained, mica flakes in a metamorphic rock?
A)
schistosity B) gneissic banding
C) slaty cleavage D) phyllitic structure
32. Metamorphic
rocks can form from
A) sedimentary
rocks B)
igneous rocks C)
metamorphic rocks D) all above.
33. For
undisturbed, horizontal strata of sedimentary rocks, their age
A) increases from top to bottom
B) decreases from
top to bottom
C) can be
determined from their color
D) is the same
34. What makes a
good index fossil?
A) big and easy to
see in the field
B) with a hard
shell that can be easily preserved
C) spans over a
long geological time period
D) widespread geographically and limited to a short
span of geological time.
35. An igneous
rock contains a radioactive isotope that has a half-life of 10 million years.
Careful analysis shows that only one quarter of the original concentration of
the parent isotope is left. How old is this igneous rock?
A) 5 million years
old B) 20 million years old C)
40 million years old D)
2.5 million years old
36. Which of the
geological era is the youngest in the geologic time scale?
A) Precambrian. B) Mesozoic. C)
Paleozoic. D) Cenozoic.
37. Lateral offset
in drainage lines is commonly associated with
A) normal faults. B)
reverse faults.
C) thrust faults. D) strike-slip faults.
38. Ductile
deformation become important when
A) the
temperature is hign
B) the confining
pressure is high
C) deformation
happens slowly
D) all above
39. In an
structural basin, the youngest strata is found
A) at the center of the basin
B) on the margins
of the basin
C) half-way
between the center and the margins of the basin
D) beneath the
older strata.
40. Which statement best describes motion on a normal fault?
A)
The hanging wall block moved downward relative to the footwall block.
B) The hanging wall block moved upward relative to the footwall block.
C) The hanging wall block moved horizontally relative to the footwall block.
D) Faults are simple breaks in the crust along which no movement has occurred.