Earth Materials, Processes and Environments
GEOL-112 Fall 2015
Practice for Lecture Test #1
Name ________________________
Part I ‑ Multiple Choice (50 pts. ‑ 2 pts. each question).
*Circle the letter of the best answer.
1) The demand for natural resources will nearly double within the next fifty years mostly due to:
a) Aging homes, buildings and infrastructure that needs replacement
b) A continued rapid increase in world populations
c) Internet trading and increased wealth in industrial nations
d) Widespread migration from agricultural areas to urban areas
2) Which of the following is used as evidence of the atom and atomic structure?
a) Study of ice crystals
b) Constancy of Interfacial Angles (in different crystals of the same mineral)
c) X-ray studies of earth materials
d) All of the above
3) Which of the following best describes noble or inert gases?
a) Atoms with equal numbers of protons and neutrons.
b) Atoms with equal numbers of protons and electrons.
c) Atoms that have filled electrons shells without sharing, losing or gaining electrons.
d) All of the above
4) Which of the following is correct for an atom of sodium with an atomic number of 11 and an atomic mass of 20?
a) It has 11 neutrons.
b) It has 11 protons.
c) It will react to gain 1 electron to fill its outermost shell.
d) All of the above
5) Which of the following bond types is responsible for weakly-held sheets of graphite?
a) Covalent
b) Metallic
c) Van der Waals
d) Ionic
6) Which of the following bond types results in high strength, low solubility and brittle behavior?
a) Covalent
b) Metallic
c) Van der Waals
d) Ionic
7) Which of the following materials is held together purely by ionic bonds?
a) Halite
b) Graphite
c) Copper
d) Diamond
8) Which of the following minerals displays simple ionic (solid) solution?
a) Plagioclase
b) Olivine
c) Quartz
d) All of the above
9) Which of following statements concerning graphite and diamond is correct?
a) They both have the same composition.
b) They are held together by different atomic bond types.
c) They are an example of polymorphs.
d) All of the above
10) Which of the following is an example of a nonferromagnesian silicate?
a) Muscovite
b) Plagioclase
c) Quartz
d) All of the above
11) Which of the following is considered a mineral?
a) Window glass
b) Petroleum
c) Table salt
d) All of the above
12) Which of the following causes melting at the atomic level?
a) Decreased electrical charges on the atoms allow them to separate.
b) Added electrons separate atoms due to an excess of negative charges.
c) Increased vibrational energy breaks atomic bonds.
d) All of the above
13) Which of the following magma conditions would result in larger (coarser) crystals?
a) High viscosity and slow cooling rate
b) Low viscosity and fast cooling rate
c) Low viscosity and slow cooling rate
d) High viscosity and fast cooling rate
14) Which of the following is an example of a rifted continent?
a) Western South America
b) Central South America
c) Northern Antarctica
d) East Africa
15) A porphyritic texture results from:
a) A two-stage cooling history
b) A slow intrusive cooling rate
c) Water-rich magma composition
d) All of the above.
16) Which of the following statements concerning scoria is not correct?
a) It has a vesicular texture.
b) It is produced by volcanic eruptions.
c) It is an extrusive rock.
d) It has a phaneritic texture.
17) Which of the following is the most important cause of melting associated with oceanic spreading ridges and rises?
a) Increased temperature
b) Increased water content
c) Decreased pressure
d) Increased heat from radioactive decay
18) A porphyritic texture records which of the following:
a) Rapid cooling of magma on the Earth’s surface
b) Slow intrusive cooling of magma beneath the surface
c) A violent eruptive history where magma is fragmented as it is ejected.
d) A two-stage cooling history involving both slow and fast cooling periods
19) Widespread magma is formed along subduction zones due to:
a) Increased temperature
b) Increased water content
c) Decreased pressure
d) Increased heat from radioactive decay
20) Which of the following best describes how obsidian forms?
a) Slow intrusive cooling of mafic magma
b) Two-stage intrusive and extrusive cooling of mafic magma
c) Violent explosive eruption and cooling of felsic/silicic magma
d) None of the above
21) A type of magma differentiation that results from the melting and addition of wall rock material to the magma is called:
a) Assimilation
b) Fractionation
c) Solid solution
d) Hydrothermal alteration
22) Which of the following is an extrusive igneous rock with a felsic (silicic) composition?
a) Andesite
b) Rhyolite
c) Scoria
d) Diorite
23) Which of the following describes violently-erupted deposits of ash and debris that have been compacted and welded during deposition?
a) Aphanitic
b) Pyroclastic
c) Porphyritic
d) Blastomitic
24) Which of the following is a mantle hot spot?
a) Ring of Fire
b) Hawaiian Island Chain
c) East Africa
d) Mid-Atlantic Ridge
25) The Sierra Nevada Mountains are underlain by a group of granite intrusions of similar age and origin called a/an:
a) Batholith
b) Dike
c) Sill
d) Megatrusion
Part II ‑ Fill in the Blank / Short Answer (50 pts. ‑ 2 pts. each question number)
26-27) Most of the volume of the atom is _________________________, while most of the mass of the atom is defined or results from the ____________________.
28) Isotopes are atoms of an element with the same ________________________ but different ________________________.
29) Define an anion. ________________________________________________
30) Why are minerals grouped according to their anion on anion complexes? ______________________________________________________________
31-32) Describe the following properties for metallic bonding:
a) Electrical conductivity (high, moderate or low): ___________________________
b) Hardness (high, moderate or low): _____________________________
c) Solubility (high, moderate or low): ___________________________
d) Breakage (malleable or brittle): ___________________________
33-34) Silica tetrahedra are linked together or bonded by ________________________ and/or __________________________. Describe how the different tetrahedra structures and linking are observed in the properties of the different silicate minerals.
___________________________________________________________________
35-36) Complete the following table with the correct colors, names and/or impurities for the following varieties of quartz:
|
Impurity |
Color |
Name |
|
None |
|
|
|
|
|
Amethyst |
|
|
Pink |
|
|
Water |
|
|
37) The silicate minerals are the most abundant mineral group in the crust because __________________________________________________________.
38) Name an example of a sulfide mineral. ___________________________
39-40) What is Bowen’s Reaction Series? Why is it useful? ______________________
__________________________________________________________________
__________________________________________________________________
41) The two most abundant elements in magma are ____________ and ___________.
42) Igneous rocks are classified according to _______________ and ______________.
43-44) Igneous rocks that have visible crystals throughout the rock are called _______________________ (textural name). Describe how these rocks form. ____
___________________________________________________________________
45) The two most important factors that determine crystal size in an igneous rock are:
______________________________ and ______________________________.
46) Name two minerals (a mineral pair) that are an example of a discontinuous reaction with the melt during gradual cooling of a magma. ______________________ and
____________________.
47) The magmatic differentiation process where a magma slowly changes composition as it melts and adds rock material from magma chamber walls is called ___________________________.
48) What is that name of an ultramafic intrusive igneous rock that is composed of mostly olivine? _____________________________
49) Name two examples of vesicular igneous rocks. ______________________ and _________________
50) Describe how pegmatites form. _________________________________________
___________________________________________________________________
Extra Credit (2 points): Name an example of a modern or active subduction zone.
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