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Volcanoes and Earthquakes - Exam 3
Questions 1 to 50 are worth two points each (100 points total),
1
Mid-ocean ridges account for
A) about 50%
2
B) about 66%
volume of volcanic activity on Earth.
_out
75%
D) more than 90%
The composition oft_._lava erupted at mid-ocean ridges is:
A) Andesite
3
of th_t_l
(/'B)_asalt
C) Rhyolite
D) Basalt and andesite
E) Basalt and rhyolite
Melting of the mantle under mid-ocean ridges occurs because:
A) Heat from radioactive decay causes melting.
he presence of water in the mantle causes melting.
ising mantle undergoes decompression melting.
oth A) and C).
E) Both B) and C).
4
During circulation of ocean water through the ocean crust close to mid-ocean ridges:
A) The water becomes very hot.
B) The water becomes mineralized.
C) Rocks of the ocean crust become hydrated.
(_oth
5
A) and B).
II of A) to C).
Mid-ocean ridges account for
A) less than 5%
6
B).about 25%
of the total number of earthquakes on Earth.
C) about 50%
_D_D_bout 85%
Mid-ocean ridge earthquakesare:
Shallow focus and mostly light
minorand
(magnitude
moderate 4(magnitude
and smaller).
4 to 6).
C) Shallow and intermediate focus and mostly minor (magnitude 4 and smaller).
D) Shallow and intermediate focus and mostly light and moderate (magnitude 4 to 6).
7
Which focal mechanism in the diagram below would be for a spreading center earthquake on the
Mid-Atlantic Ridge? [North is up; Le., at the top of the page.]
B
8
C
D
Which type of volcano characterizes subduction zones?
A) Caldera
B) Cinder cone
C) Shield volcano
"/' D)_Stratovolcano
k_J
k'l
GEOL 1003 Exan_3
9
•"_'_ "
n
(,.e..
what
me,ts),n
subducf,on
ess.•
"¢_ i _', _ ......
eddotite of the mantle wedge
D) Peddotlte of the over-dding plate
BSedimentsubducted
oth basalt of the subducting
into the mantle
plate and peddotiteB)ofBasalt
the mantle
of the wedge
subducting plate
_)
10 Comparedtooceanicvolcanicarcs,
_)
Lesser proportion
Lesser proportion
Greater proportion
D) Greater proportion
incontlnentalvolcanicarcsthereiserupteda:
of basalt and a lesser proportion of rhyolite.
of basalt and a greater proportion of rhyolite.
of basalt and a lesser proportion of rhyolite.
of basalt and a greater proportion of rhyolite.
11 The difference between the compositional
(previous question) is because:
A)
B)
C)
(_
spectrum
of continental
arc and oceanic arc lavas
There is a difference in the composition of the original magma in the two arc settings.
There is a greater amount of crystal fractionation of rising magma in the continental arc setting.
There is interaction of magma with the continental crust in the continental arc setting.
Both A) and B).
Both B) and C).
12 The 1628 BC eruption of the volcano Thera (Santorini) probably is the origin of the myth of Atlantis.
Thera is located in the:
(_)Atlantlc
Ocean
B) Indian Ocean
C) Mediterranean Sea
D) Pacific Ocean
13 Which volcano had an historic eruption that produced the "year without summer" in Europe and North
America in the year after the eruption?
A) Mt. Pelee
B) Tambora
G
Thera
D) Vesuvius
"
14 The 1985 eruption of a volcano in Colombia produced lahars that killed over 20,000 people. Which
volcano?
Purace
A) Galeras
B) Huila
C_evado
del Ruiz
D)
15 In 1984 and 1986 carbon dioxide released from two crater lakes killed people (by asphyxiation) in
which west African country?
(_Cameroon
B) Ivory Coast
C) Nigeria
D) Senegal
16 Over the last 4,000 years the Cascade Range volcano that has erupted most frequently is Mt.
Rainier.
A) True
_alse
17 In the 1980 eruption of Mt. St. Helens:
A) The initial visible activity was small ash and steam (phreatic) eruptions.
B) There was about two months between the initial activity and the major eruption in May.
C) The major eruption produced a debris avalanche, a pyroclastlc surge, air-fall deposits, and
lahars.
,,_Both
A) and C).
All of A) to C).
18 The VEI 5 major eruption of Mt. St. Helens on 18 May, 1980, was triggered by:
A) A swarm of many small earthquakes (<M3) under Mt. St. Helens.
_)
_ moderate earthquake (M5) under Mt. St. Helens.
ntrusion of basalt magma into the magma chamber.
udden, spontaneous release of gas from the magma chamber.
GEOL 1003 Exam 3
19 In late 2004 a new eruption began at Mt. St. Helens. This eruption has produced:
A) An initial moderately explosive (vulcanian) eruption followed by eruption of andesite lava flows.
Moderately explosive (vulcanian) eruptions every few weeks.
ruption of a lava dome with occasional phreatie explosions.
ruption of a lava dome with occasional pyroctastic flows from lava dome collapse.
20 As of now, November 2009, the eruption of Mt. St. Helens that began in late 2004:
A) Continues; lava is currently being erupted.
(_ls
paused; no lava is currently being erupted, but the eruption has not ended.
Has ended.
21 The 1991 eruption of Mt. Pinatubo was:
A) Unsuccessfully predicted; unsuccessful because the eruption occurred before the predicted
time.
B) Unsuccessfully predicted; unsuccessful because the eruption occurred after the predicted time.
C) Successfully predicted, but no lives were saved because the Philippine authodties did not act on
(_pp_e
prediction and did not evacuate people.
uccessfully
predicted,
many
(probably
tens of thousands)
Philippine
authorities
didand
act on
the lives
prediction
and evacuated
people. were saved because the
22 The 1991 Pinatubo eruption was the:
A) Largest eruption in the last 500 years
C) Largest eruption in the last 100 years
B_Second
largest eruption in the last 500 years
D____econd largest eruption in the last 100 years
23 Compared to the 1980 eruption of Mt. St. Helens, the 1991 Mt. Pinatubo eruption produced about
times the amount of/_clastic
A) 10;5
deposits; therefore it was a VEI __ eruption.
(" B)jIO;6
C) 100;6
D) 100;7
24 The 1991 eruption of Mt. Pinatubo injected large amounts of sulphur dioxide (SO,) gas high into the
atmosphere. Over the few years after the eruption this gas:
A) Caused a significant but small (less then 1°C) drop in global surface temperature.
B) Caused a significant large (greater than 5°C) drop in global surface temperature.
Had no significant effect on global surface temperature.
Caused a significant but small (less than 1°C) rise in global surface temperature.
Caused a significant large (greater than 5°C) rise in global surface temperature.
25 The eruption that began in 1995 on the Caribbean island of Montserrat has produced:
A) A lava dome.
B) Pyroclastic flows and air-fall from collapse and explosion of the lava dome.
C) Lahars from heavy rainfall on pyroclastic deposits.
(_)Both
A) and C).
All of A) to C).
26 The Montserrat eruption:
A) Was small and localized and had little impact on the island.
B) Somewhat affected the southern part of the island and resulted in the short-term evacuation of a
small proportion of the population.
Devastated
thepopulation
central and
of most of the
of southern
the island.parts of the island and resulted in the long-term evacuation
D) Devastated the entire island and resulted in the long-term evacuation of the total population of
the island.
27 During the Montserrat eruption there have been periods of lava dome growth separated by periods
when lava was not being erupted (quiescence). As of now (October-November 2009):
(_qlVa
is being erupted and the lava dome is growing.
e lava dome stopped growing a number of months ago and the eruption is paused
uiescence).
e lava dome stopped growing a number of months ago and the eruption has officially (by the
Montserrat Volcano Observatory) been declared to have ended.
28 Of the total energy released g_obally by earthquakes,
zone earthquakes?
A) 50%
B) 75%
what percentage is released by subduction
C) 90%
CD_98%
E) 100%
29 Earthquakes in subduction zones occur to as deep as 700 km, but no deeper. This is because:
A) 700 km is the greatest depth to which we can record earthquakes.
B) The subducting plate has broken up by the time it reaches 700 km depth in the mantle.
(_!he
subducting plate remains intact but does not go deeper than 700 km in the mantle.
he subducting plate remains intact and does go deeper than 700 km in the mantle, but has
eleased all of its stored stress by 700 km depth.
30 The largest magnitude earthquakes in subduction zones are of:
A) Shallow focus and occur in the subducting plate where it starts to bend.
haallowfocus and occur in the over-riding plate.
allow focus and occur on the mega-thrust boundary between the subducting and over-riding
tes.
D) Intermediate focus and occur in the subducting plate.
E) Deep focus and occur in the subducting plate.
31 A large tsunami in January 1700 caused extensive damage along the east coast of Japan. The
earthquake that triggered_nami
A) Aleutian
occurred in the
C._ascadia
trench.
C) Mariana
D) Peru-Chile
32 The shallow part of the Cascadia subduction zone has produced very few earthquakes (is aseismic)
over the last 50 years. This is because:
Subduction of the Juan de Fuca plate under the North American plate has stopped.
,,_:_here is continuous, smooth slip (creep) on the fault plane between the two plates.
_he
fault plane between the two plates is completely locked.
33 On the Cascadia subduction zone:
(_he
recurrence interval for M9 earthquakes is about 50 years.
he recurrence
recurrence interval for M9 earthquakes is about 500
years.
5,000
years.
D) Earthquakes as large as M9 do not occur.
34 The December 2004 Great Sumatra earthquake:
•/A) Occurred on a segment of the subduction zone that had very few earthquakes in the previous 40
years (a seismic gap).
B) Was of intermediate focal depth.
WaS larger than M8.5.
oth A) and C).
oth B) t_ C).
GEOL 1003 Exam 3
35 The tsunami generated by the 26 December, 2004, Great Sumatra earthquake was recorded in the
Atlantic and Pacific Oceans.
A) True
(B_ False
36 The May 2008 Sichuan, China, earthquake:
A) Was a great (M8.0 or larger) earthquake.
B) Occurred on a thrust fault.
(_) AKilledless than 100,000 people because the quake was predicted and people evacuated.
Both A) and B).
ttof A) to C).
37 Volcanic activity is rare on transform faults. Where it does occur it is associated with:
A) Ridge-ridge transform faults.
B) Ridge-subduction transform faults.
C) Subduction-subduction transform faults.
ansform fault segments where there is transpression.
ansform fault segments where there is transtension.
38 Which focal mechanism in the diagram below would be for an earthquake on a right-lateral transform
fault on the Mid-Atlantic Ridge? [North is up; Le., at the top of the page.]
B
C
39 The earthquake hazard to the Bay Area (San Francisco and Oakland) is from:
A) The Calaveras fault.
B) The Hayward fault.
C) The San Andreas fault.
(_ABOth B) and C).
II of A) to C).
40 On the creeping segments of the San Andreas, Hayward, and Calaveras faults the seismic hazard is
on the non-creeping segments of these faults.
ower than
B) the same as
C) higher than
41 The Hayward fault last produced a large earthquake (M6.8) in 1868. The present-day seismic risk to
the Bay Area from the Hayward fault is:
A) Negligible because the average recurrence interval for large earthquakes on the Hayward is
about 1,000 years.
ery serious because the average recurrence interval for large earthquakes on the Hayward is
_,_p_ye_a[s con_seque_nt
y a a[ge earthquake on the Hayward is very likely in the near future.
C) Extremely serious because the average recurrence interval for large earthquakds_on the
Hayward is 50 years; consequently, a large earthquake on the Hayward is long overdue.
42 This California earthquake is significant because it triggered a large earthquake on_arby
A) 1906 San Francisco
B) 1975 Oroville
C) 1989 Loma Prieta
_1992
fault:
Landers
r
GEOL 1003 Exam 3
43 Atthe "big bend" in the San Andreas fault (to the north and east of Los Angeles) there is:
(_l'ranspression,
and therefore a component of normal faulting.
"-B') Transpression, and therefore a component of reverse/thrust faulting.
..G)_ranstension, and therefore a component of normal faulting.
,J_Transtension, and therefore a component of reverse/thrust faulting.
44 The 1906 San Francisco earthquake:
A) Was a great (M8.0 or larger) earthquake.
B) Caused less than 10,000 fatalities.
C) Made almost 250,000 people homeless.
•_.)_B0th A) and C).
_Both
B)._).
45 Which focal mechanism in the diagram below best represents the 1906 San Francisco earthquake?
[North is up; i.e., at the top of the page.]
B
46 The 1989 Loma Prieta earthquake was forecast the year before the earthquake occurred (Le., in
1988).
rue
B) False
47 The 1994 Northridge earthquake occurred on a:
A) Left-lateral strike-slip fault.
B) Right-lateral strike-slip fault.
(_everse/thrust
fault.
lind reverse/thrust fault.
48 Compared to the M6.7 1994 Northridge earthquake, in the M6.9 1995 Kobe earthquake there were:
A) Many fewer fatalities and much less (in $ terms) damage.
(_A
similar number of fatalities and a similar amount (in $ terms) of damage.
Many more fatalities and much more (in $ terms) damage.
49 In both the Northridge and Kobe earthquakes the only bridges that collapsed were those:
A) At the epicenter.
l-hat were not reinforced/strengthened.
B) Carrying the heaviest traffic.
D) Made of steel.
50 The large volcano ont/_ltalian
island of Sicily that has had numerous eruptions in historic time is:
A) Etna
,/ B),E;tromboli
C) Vesuvius
D) Vulcano
Name :
Volcanoes and Earthquakes : Exam 2
Questions 1 to 50 are worth two points each (100 points total).
1
A stratovolcano is a:
A) Small volcanic cone with steeply dipping flanks constructed of basaltic pyroclastic deposits from
a single eruption.
B) Large volcanic cone with gently dipping flanks constructed by numerous passive eruptions of
basalt lava flows.
C) Large volcanic cone with gently dipping flanks constructed by numerous passive and explosive
ruptions of andesite or higher silica lava.
arge volcanic cone with steeply dipping flanks constructed by numerous passive eruptions of
asalt lava.
l
E) Large volcanic cone with steeply dipping flanks constructed by numerous passive and explosive
eruptions of andesite or higher silica lava.
2_an°'2
A
C) Mt. St. Helens, Washington
nO_ _It.
Fuji, Japan
"-D) Vesuvius, Italy
3
_d
volcanoes are characteristic of which geological setting on Earth?
4
_.__Hotspots
B) Mid-ocean ridges
C) Subduction zones
Olympus Mons, the largest volcano in the Solar System, is e:
hield volcano on Mars
-C) shield volcano on Venus
5
B) stratovolcano on Mars
D) stratovolcano on Venus
Volcanic activity in the western US is related to:
A) A hotspot
6
D) Transform faults
(/'B)j_ubduction
C) Continental rifting
D) All of A to C
An extremely large and violent explosive eruption that produces a very high eruption column and
major pyroclastic flow/_-_om eruption column collapse is termed:
A) hawaiian
7
8
C) plinian
D) strombolian
E) vulcanian
Worldwide, approxihtafely how many volcanoes are in eruption at any given time?
5OO
B) 60
,_15
C)
D) t,300
E) 2,500
A volcano with a repose time of 15,000 years last erupted 9,000 years ago. This volcano would be
(_acterized
9
/ B) _eleean
as
active
B) dormant
C) erupting
Volcanic eruptions most commonly are triggered by:
_A_arthquakes
///C)/Recharge
10'-On the VEI
of the magma chamber
scale, a VEI 4 eruption is
A) 2
11 /,_u_toric
(_,Krakatau,
B) 10
B) Rainfall
D) Vesiculation in the magma chamber
times larger than a VEI 2 erupt_l_
C) 100
I_)1,000
time there has only been one VEI 7 eruption. Which eruption?
1883
D) extinct
B) Mt. St. Helens, 1980
/E)_10,000
,,.../
.
C) Pinatubo, 1991
D) Tambora, 1815
d
GEOL 1003 : Exam 2
12 VEIL8 _mega;eruptlons'_ifr9,_mca_l_:)er-volcanoes:
A) Are of rhyolite magma and highly explosive.
B) Are caldera-forming.
C) Occur approximately every 500,000 years.
_D)_oth
A) and B).
II of A) to C).
13 VEI 8 "mega-eruptions" from "supervolcanoes" have:
A) No impact on global climate.
B) A significant impact on global climate, causing climate cooling in the years following the
(_
eruption.
A significant
eruption.
impact on global climate, causing climate warming in the years following the
14 The most recent VEI 8 eruption occurred 74,000 years ago. This was an eruption of:
A) Tambora
B) Tebe
K_)
_esuvius
D) Yellowstone
15 Volcanoes with short repose times (years to tens of years) typically have larger eruptions (higher VEI)
than volcanoes with long repose times (hundreds to thousands of years).
A) True
(ZB_False
,.
16 Historically, the volcanic product that has caused the second greatest number of human fatalities is:
A) Air-fall ash
B) Lahars
(_.ava
flows
D) Pyroclastic flows
17 The point on the Earth's surface directly above the point inside the Earth where an earthquake occurs
med the _
of the earthquake ....
picentre
B) hypocentre
C) quakicentre
18 A fault occurs when rockb_esasa(n)
A) brittle-plastic
material
_ _lastic-brittle
C) elastic-ductile
19 The fault shown in the block diagram to the right is a:
(A)
Normal fault
C) Blind normal fault
'
B) Reverse/thrust fault
D) Blind reverse/thrust fault
20 The fault shown in the block diagram to the right is a:
"/_Normal
left-lateral oblique-slip fault.
_B)..Reverse left-lateral oblique-slip
//_Normal
D) supercentre
fault.
right-lateral oblique-slip fault.
everse right-lateral oblique-slip fault.
rll_llt,j__.'_'_
D) elastic-plastic
GEOL 1003 : Exam 2
21 The photo to the right is of rock layers exposed in a
vertical road cut. These rock layers are:
A) Not faulted.
B) Faulted by a normal fault.
C) Faulted by a reverse fault.
D) Faulted by a left-lateral stdke-slip fault.
(_aulted
by a right-lateral strike-slip fault.
22 At subduction zone plate boundades faulting is characteristically of the
A) normal
B) oblique-slip
23 The San Andreas Fault is a
fault.
A) normal
B) reverse
_
type.
D) stdke-slip
reverse
C) left-lateral strike-slip
ight-lateral strike-slip
24 Rock has variable strength under different stresses. The strength of rock, from weakest (least force to
break) to strongest (most force to break), with stress is in the order:
A) compression; extension; shearing
C) extension; compression; shearing
/_compression;
shearing; extension
_" D)_extension; shearing; compression
25 The strength of rock under different stresses (previous question) means that, in general terms, the
s(_st otspots
earthquakes occur
B) Mid-ocean
at:
ridges
C) Subduction zones
D) Transform faults
26 On a particular plate boundary strike-slip fault earthquakes occur with a recurrence interval of 150
years and the displacement on the fault in each earthquake is 7.5 metres. Therefore, the relative
velocity of the two plates is __
A) 2
centim_e_year.
B) 3
C C)_4
g) 5
E) 6
27 P-waves travel through:
A) Only liquids
B) Only solids
_Both
solids and liquids
D)
Neither solids
nor
liquids
28 Rayleigh waves have a vibration direction that is:
_)
parallel to the direction in which the wave is travelling.
erpendicular to the direction in which the wave is travelling.
erpendicular to the direction in which the wave is travelling and parallel to Earth's surface.
D) Retrograde elliptical.
E) Prograde elliptical.
29 The order, first arrival to last arrival, in which a seismic station will detect seismic waves from an
earthquake is:
(_ove,
Rayleigh, P, S
13)P, Rayleigh, S, Love
, S, Love, Rayleigh
D) P, S, Rayleigh, Love
30 A seismograph works on the basis of the principle of
A) impulse
B) ineptitude
JC_nertia
D) momentum
GEOL 1003 : Exam 2
31 Almost 2,000 years ago the Chinese invented the seismoscope, a simple type of seismograph. It was
able to:
A) Detect a distant earthquake that was not felt at the location of the seismoscope.
_)
BGivean indication of the focal depth of the earthquake.
stimate the magnitude of the earthquake.
oth A) and B).
E) All of A) to C).
32 Measurement of the ground motion close to the epicentre of a large earthquake requires the use of:
A) a horizontal broadband seismograph.
(_)
b vertical broadband seismograph.
strong motion seismograph.
oth A) and B).
33 For a seismograph station with three broadband seismographs recording the E-W horizontal ground
motion (the E component), the N-S horizontal ground motion (the N component), and the vertical
ground motion (the Z component), P-waves will show up best on the: _
A) E component
B) N component
C) E and N components
/(/Dj) _Zcomponent
34 With increasing distance of seismic stations from the epicentre of an earthquake,
between the time of arrival of the P-wave and of the S-wave (the S - P time):
A) deceases
B) is constant
_-'_
i.i.i_creases
the difference
D) varies erratically
35 The National Earthquake Information Center (NE1E_ rapidly and accurately locates (epicentre, time of
occurrence, focal depth) worldwide earthquakes based on the:
-wave arrival time for one seismograph station.
-wave arrival time for many seismograph stations.
- P time for one seismograph station.
D) S - P time for many seismograph stations.
36 The Mercalli Intensity scale is a:
A) Qualitative scale that ranges from intensity ] to intensity XII.
(__B
Qualitative scale that ranges from intensity 1 to intensity XIV.
uantitative scale that ranges from intensity 1to intensity Xll.
D) Quantitative scale that ranges from intensity 1to intensity XIV.
37 Compared to solid rock (granite, etc.), in sand, mud, and land-till:
_) _heismicwaves travel slower and are of larger amplitude.
eismic waves travel faster and are of smaller amplitude.
ere is liquefaction and a loss of mechanical strength.
D) both A) and C).
E) both B) and C).
38 T_argest
earthquake ever recorded was the
earthquake.
_'1906
San Francisco
B) 1960 Chile
C) 1964 Alaska
D) 2004 Sumatra
39 The Moment magnitude scale has replaced the Richter magnitude scale because the Richter scale
underestimates the size of large earthquakes (M7.3 and greater).
A) True
40 AtA)
the-5present time,
@alse
the smallest recordable e_quakas
B)-2to-3
/'C))
to2
LJ
are of about magnitude
D) 2to3
E) 5
GEOL 1003 : Exam 2
41 Which of the focal mechanisms (beach-ball diagrams) below best represents earthquakes occurring
in the Peru-Chile trench? [North is up; i.e., at the top of the page.]
B
D
42 Which of the focal mechanisms (beach-ball diagrams) below best represents earthquakes occurring
on the San Andreas fault? [North is up; i.e., at the top of the page.]
B
C
D
43 In terms of earthquake magnitude:
(_TmheOretically and practically the maximum possible magnitude is about 10.
heoretically there is no maximum possible magnitude, but practically the maximum possible
agnitude is about 10.
C) Theoretically there is no maximum possible magnitude, but practically the maximum possible
magnitude is about 15.
D) Theoretically and practically there is no maximum possible magnitude.
44 V_increasing
distance from the epicentre of an earthquake:
A)J]-he Mercalli intensity decreases, the magnitude decreases.
"t_ The Mercaili intensity decreases, the magnitude is constant.
C) The Mercalli intensity is constant, the magnitude decreases.
D) The Mercalli intensity is constant, the magnitude is constant.
45 Compared to a M2 earthquake, a M4 ea_ake
A) 2
B) 100
releases __
times as much energy.
'_C)JS00
D) 1,000
v
E) 27,000
46 In terms of great, M8.0 or larger, earthquakes globally, compared to the long-term (since 1900)
average this year (2009) so far (October) has been:
A) Below average; there have been no great earthquakes.
_)
AAverage;there has been one great earthquake.
Above average; there have been two great earthquakes.
bore average; there have been three great earthquakes
47 Subduction zone earthquakes occur at foc.c.c_depthsof__
/_)
0 to 70
B) 0 to 300
(" C)/0 to 700
kilometres.
D) 70 to 300
E) 70 to 700
GEOL 1003 : Exam 2
48 In an average year there is one great, M8 or larger, earthquake globally. In terms of the annual global
energy budget of earthquakes, one great earthquake releases:
_)
Less energy than
Less energy than
The same amount
D) More energy than
the three milrion earthquakes that are M3 or smaller.
all of the earthquakes that are smaller than M8.
of energy as all of the earthquakes that are smaller than MS.
all of the earthquakes that are smaller than M8.
49 In 1993, nine peopte (6 volcanologists and 3 tourists) were killed by a rain of blocks and bombs in a
small eruption of a volcano in Colombia. Which vorcano?
A)
Dona Juana
B) Galeras
_C_Nevado
del Ruiz
D) Purace
50 A European city was devastated by an earthquake in 1755. Which city?
A) Lisbon
B) London
C) Madrid
(f_aples
Name
Volcanoes
:
and Earthquakes
: Exam 1
Questions 1 to 50 are worth two points each (100 points total).
1
Which is not part of the scientific method?
atural phenomena are explained in terms of natural processes.
bservations and data are used to formulate an hypothesis•
C) The hypothesis is used to make predictions, and those predictions are then tested.
D) A rigorously tested and accepted hypothesis becomes a theory.
E) A theory is not falsifiable, i.e., cannot be disproved.
2
In science, plate tectonics and evolution are
A) untested hypotheses
C) untested theories
3
B) well-tested and accepted hypotheses
_vell-tested
and accepted theodes
E) laws
Which was not a piece of evidence that Alfred Wegener used to argue the case for continental drift?
at fossils of the same freshwater and land reptiles are found in Africa and South America.
at ancient volcanic rocks are found in Africa and South America.
C) That rock types and ages match up between Africa and South America when the Atlantic Ocean
__. is 'closed'.
-,
/fD) That ancient glacial deposits are found on continents now near the equator.
4
Wegener proposed that 200 million years a supercontinent existed that he named
A) Gondwanaland
5
B) Panamerica
D) Tethys
______angaea
The general rejection of Wegener's continental drift hypothesis by the 1930s was due to the inability
of the hypothesis to explain:
A) Why fossils of the same ancient animals and plants are found in both Africa and South America.
B) Why deposits from ancient glaciations are found on continents now close to the equator.
C) Why the types, ages, and structures of ancient rocks match when the African and South
.
(_Ameriean
6
continents are fit together.
e mechanism whereby the continents could move around Earth's surface.
An ancient lava flow has a. magnetization direction that points (declination) to the south and
(inclination) down into the ground at a low angle. This lava flow was erupted and crystallized at:
A) Low northern latitude during a time of normal magnetization.
B) Low southern latitude during a time of normal magnetization.
.,_ The equator during a time of either normal or reverse magnetization.
"/_D))Low northern latitude during a time of reverse magnetization.
Low southern latitude during a time of reverse magnetization.
7
Which piece of evidence was the "foundation stone" for the development of plate tectonic theory?
A) That submarine mountain ranges - mid-ocean ridges - are found in all of the major ocean
_
8
basins (Atlantic, Indian, Pacific).
T,_e4_gn_
stripes associated with mid-ocean ridges could be explained by the
process"6_ sea-flo6r _pre:_ding.
C) That deep ocean trenches could be explained by the recycling of sea-floor into the Earth.
D) That hotspot volcanic islands could be explained by mantle plumes.
At which type of plate boundary is old plate destroyed?
A) Fracture zone
B) Mid-ocean ridge
f_C)"_ubduction
L_J
zone
D) Transform fault
GEOL 1003 : Exam 1
9
At wh,c_."_pe ,oftplate,,bou _;$r_
A) Fracture zone
plat e con served?
B) Mid-ocean ridge
C) Subduction zone
10 At which type of plate boundary do the greatest numberof
but their impact is negligibJ#?
A) Fracture zone
_ B))Vlid-ocean ridge
11 The Himalaya mountains a_
A) Africa and Arabia
__
_E))_'ransform
volcanic eruptions and earthquakes occur,
/
C) Subduction zone
/
result of cont_inent collision between:
B(_frica
and Eurasia
fault
/D_ Transform fault
'
C) India and Africa
D) India and Eurasia
12 The plates (lithosphere) are able to move because the layer underneath them (the asthenosphere) is:
A) Hot and solid, but of different composition and much higher density, such that the lithosphere
(_Hiloats
on the asthenosphere.
ot and solid, but of low rigidity and capable of flow on a long time-scale, allowing the cold, dgid
ithosphere to slide around on it.
C) Hot and melted, allowing the cold, rigid lithosphere to slide around on a liquid layer.
D) None of A) to C).
13 The North American and Eurasian plates are separating across the Mid-Atlantic Ridge•
Consequently, since the Declaration of Independence the distance between North America and
Europe has increased by approximately.
(_10
B)
centimetres
10 kilometres
(_)'_0
D)
metres
10 millimetres
14 A hotspot volcanic island on the Indian plate is composed of lava flows that are 5 million years old
and the island is now 300 kilometres away from the location of the mantle plume that caused the
volcanism. Therefore, the rate of absolute motion of the Indian plate over the mantle plume is:
A) 2 centimetres per year.
B) 4 centimetres per year•
(_)6 centimetres per year.
D) 8 centimetres per year•
15 Plate tectonics is driven by Earth's internal heat• That heat is transferred from the deep interior to the
surface of Earth by:
A) Advection
B) Conduction
(C/_onvection
D) Radiation
16 Mafic minerals are
_)
digarkin colour and
ark in colour and
ht in colour and
D) light in colour-and
relatively
relatively
relatively
relatively
low in density.
high in density.
low in density.
high in density.
17 Which is nota mafic mineral?
A) Amphibole
B) Olivine
C) Pyroxene
(_D)_uartz
V
18 Which describes rhyolite?
A) Light in colour•
D) Both A) and C).
19 Comparedto
rhyolitelava,
LfC_"Low in eruption temperature.
B) Low in silica content.
E) All of A) to C).
andesite lava has
_)4ower silica, lower eruption temperature
C) higher silica, lower eruption temperature
('_ lower silica, higher eruption temperature
"13) higher silica, higher eruption temperature
IouJ
P--
%
GEOL 1003 : Exam 1
20 Magma originates in the uppermost part of Earth's 2,9OO-km-thick mantle, which is composed of the
rock peddotite. Melting of mantle peridotite produces
magma.
(_oasalt
B) andesite
C) rhyolite
D) basalt, andesite, and rhyolite
21 Crystal fractionation of magma in a magma chamber results in
of the remaining,
residual, magma.
A) a decrease in both the silica and water content
a decrease in the silica content and an increase in the water content
n increase in the silica content and a decrease in the water content
n increase in both the silica and water content
22 Rhyolite lava is about 1,0OO,O00times more viscous than basalt lava. This is because, compared to
basalt lava, rhyolite lava is:
A) higher in silica content.
_,
_"_
_B_)
higher in eruption temperature.
both A) and C).
lower in eruption temperature.
"-15) both A) and B).
23 At low pressure (Le., at shallow depth in the Earth) magma contains more dissolved gas than at high
pressure (Le., at great depth in the Earth).
A) True
Oalse
24 The most explosive volcanic eruption will occur for:
magma
B) Basalt
of high water content.
D) Rhyolite magma of high water content.
magma
"_Basalt
of low water content.
"13) Rhyolite magma of low water content.
25 Volcanic gases can be hazardous as a result of:
A) Short-term exposure to low gas concentration.
B) Short-term exposure to high gas concentration.
C) Long-term exposure to low gas concentration.
__l_Both
A) and B).
(f_ ,12f)j_oth B) and C).
I
26 In 1986, 1,700 people in Cameroon, West Africa, died as the result of a burst of
from the crater lake of a volcano.
(_arbon
dioxide (COz)
ulphur dioxide (SO2)
27 A1_oehoe
gas
B) carbon monoxide (CO)
D) water (H,O)
lava flow has a rough, blocky surface.
(_-rue
B) False
28 The hazards associated with a lava dome are that:
A) The low viscosity dome lava can flow down the flanks of the volcano very fast.
B) Gas pressure can build in the dome, resulting in explosion of the dome.
C) The dome can develop steep sides, resulting in collapse of the dome.
(_Both
B) and C).
All of A) to C).
29 For jet aircraft the cloud of volcanic gas and ash injected high into the atmosphere during a large
explosive eruption is:
A) Insignificant; jets fly through gas and ash clouds without noticing.
B) A slight problem because visibility is reduced.
(_
significant problem because the plane becomes more difficult to maneuver.
major problem because the ash sucked into jet engines can cause them to shut down.
GEOL 1003 :"Exam 1
30 Air-fall ash is hazardous hundreds of kilometres from an erupting volcano because it can:
A) Cause building roofs to collapse because of the weight of ash.
B) Disrupt transportation and communication.
lgnite vegetation because the ash is so hot.
Both A) and B).
All of A) to C).
31 Volcanic cinders are
_)
_aerysmall (powdery) fragments of lava
mall (roughly pea-sized) fragments of lava
rge (fist-sized or bigger) angular piece of rock
D) large (fist-sized or bigger) rounded or elliptical blob of lava
32 Pyroclastic flows and surges can be produced by:
ravitational
ravitational collapse
collapse of
of aanlava
eruption
dome.column.
B) Both
D)
Explosion
A) ancl
of B).
a lava dome.E) All of A) to C).
33 Pyroclastic flows and surges are the most hazardous volcanic product. If you are caught in a
pyroclastic flow or surge you are
likely to die than to be injured_,,._
and survive.
A) ten times less
B) two times less
C) two times,more
(D)_ten times more
34 The large explosive 1980 Mt. St. Helens, 1991 Pinatubo, and 1995 Montserrat eruptions all were
ded by phreatic eruptions.
rue
35 Alahar is a
B) False
A) low density mixture of air and votcanic ash
B) ,very dense and mobile mixture of rock and lava fragments with hot volcanic gas
Avery
dense and mobile mixture of rock and lava fragments with water
"E)) type of rhyolite lava flow with a smooth surface
36 In terms of the hazards posed by volcanic products, lahars are:
A) Less hazardous
(_Mess
hazardous
ess hazardous
ore hazardous
than both lava flows and pyroclastic flows.
than lava flows but more hazardous than pyreelastie flows.
than pyroctastie flows but more hazardous than lava flows.
than both lava flows and pyroclastic flows.
37 In 1902 some 30,000 people died in a volcanic event on the Caribbean island of Martinque
associated with the volcano Mt. Pelee. They were killed by:
(_
lava
pyroclastic
flow. flow.
B) Volcanic
E)
A debris avalanche.
gases.
C) A lahar.
38 In 1985 some 22,000 people died in a volcanic event in Colombia associated with the volcano
Nevado del Ruiz. They were killed by:
_)
A lava
pyroclastic
flow. flow.
B) Volcanic
E)
A debris avalanche.
gases.
C) A lahar.
39 The devastating 26 December, 2004, Indian Ocean tsunami was the result of:
A) Eruption of a volcano in Indonesia.
Sector collapse of a volcano in Indonesia.
A very large earthquake on the Indian Ocean ridge.
A very large earthquake in the Java trench.
GEOL 1003 : Exam 1
40 At the time of the December 2004 tsunami (previous question) there was a tsunami warning system
for the Indian Ocean, but this system malfunctioned and gave no waming of the tsunami.
A) True
_alse
41 In the Atlantic Ocean there is a:
Negligible tsunami
Significant
seismogenic
hazard
tsunami
from any
hazard
source.
from earthquakes on the Mid-Atlantic Ridge.
C) Significant volcanogenic tsunami hazard from volcanic eruptions on Iceland.
D) Significant volcanogenie tsunami hazard from sector collapse of ocean island volcanoes.
E) All of B) to D).
42 As Simon Winchester points out, the speed and effectiveness of the federal government response to
06 San Francisco earthquake disaster and the 2005 hurdcane Katrina disaster was:
uch worse in 1906 than in 2005.
milar in 1906 and 2005.
C) Much better in 1906 than in 2005.
D) Very slow and ineffectual in both 1906 and 2005.
43 The 1906 San Francisco earthquake was the first major earthquake to which the overwhelming
nse was one that sought to understand the natural causes of the earthquake.
rue
B) False
44 The major eruption of Vesuvius that destroyed the Roman cities of Pompeii and Herculaneum
occurred in
A) 1979 BC
C_79
BC
C) 79 AD
D) 1979 AD
45 The largest earthquake ever recorded occurred in
A) San Francisco in 1906
Lt"-B)_hile
in 1960
v
C) Alaska in 1964
D) Indonesia in 2004
Questions 46 to 50 refer to the attached map of the world which shows the continents (white), the oceans
(grey), and the plate boundaries (thick black lines). The major plates are numbered from 1 to 14, and
some major geological features are lettered from A to H. From the map:
46 Which number is_
A)1
Arabian plate?
[ By
%=
Cl3
D)5
E)6
C) 11
D) 12
E) 14
47 Which number is={T_eCocos plate?
A) 7
48 V_ch
(B)_0
letter is the mid-ocean ridge in the Pacific Ocean?
B) C
C) E
D) G
E) H
49 Which letter is a subduction plate boundary?
A) B
B) C
C) E
50 Which letter is a major hotspot in t_tlantic
A)B
B)c
4c)
L.Y
_
E) H
Ocean?
D)E
.E)
Earthquakes
and Earth's
Interior-
Name:
Chapters
19 and 20
_"
//t_
TA name or Section #
Objectives: by the end of this lab you should be able to:
*
Examine an earthquake seismogram and recognize the P waves, S waves, and surface waves.
*
Use a seismogram and travel-time graph to determine how far a seismic station is from the epicenter
ofan earthquake.
*
*
*
*
*
Determine the actual time that an earthquake occurred using a seismogram and travel-time graph.
Locate the epicenter of an earthquake by plotting seismic data from three seismic stations.
Explain how earthquakes are used to determine the structure of Earth's interior.
List the name, depth, composition, and state of matter of each of Earth's interior zones.
Describe the temperature gradient of the upper Earth.
*
Explain why Earth scientists think that the asthenosphere consists of partly melted, plastic material at
a depth of about 100 kilometers.
*
Explain how earthquakes and Earth's temperature gradient have been used to explain the fact that
large, rigid slabs of the lithosphere are descending into the mantle at various locations on Earth.
1. It took approximately (5, 7,fi-_)minutes.
2.(_Fiv_ seven) minutes elapsed between the first P and S waves
3.
(Five, sev_
minutes elapsed between the first P and surface waves
4. Maximum amplitude is approximately (__times
greater
0_-""
5. The approximate period is (10_/3_ 60)
6. The period of the surface waves is_
less)
7. Difference in arrival times_eases)
8. tO00 miles:
"_
minutes difference
(,._ "'3,_
2400 km:
Uf
minutes difference
_._ - _, _
(O, _
minutes difference
IS-
3000 miles:
9.
_r 0 t_ 0
_,2
miles
10. The first p wave arrived approximately (3_ 14) minutes after
11.
i0 _'_
P.M. local time
12.
? New,:Y6r_;_ _""
' " _
-:. :""_Seattle':..:.,::'_
_5_xic&,CityS
Elapsed time between first P and first S waves
Distance from epicenter in miles
(Q [q(_ _(..)
"_0
L.__,)q _],)
I_.)_.._
13. Label the cities on the figure below (approximate locations have been provided)
14. Draw distance circles on the figure below
_, 513"_ itr_
I I O_3
'
20. Extends to a depth of about (18_250)
a. Zone B is (crust,__
kilometers
core)
h.Velocity
_incr__2_
c. Zone B (is_
s'tml
ar---l_'_to-_to
Zone A
21. Extends to a depth of about
c:_qO_
a. Zone C is called Earth's
r)(-_(--i
kilometers
_/¢0__
b. 5-_C_e-S (._nr'O_ +g_veA fhrc_qV_ li__c&_
22. Extends to abo_6100)
kilometers
a. ZoneO isEarth's Ott-I'C'T._
('_
-0
.
c. Velocity (increases,
23. Zone E is Earth's
_
,
0(_ _._
a. Extends from a depth of
$
C.o¢2_
_
OO
O
_f_f'_Tgt
_'k
km to the
CAP.[ "] "_.l_
of Earth
"
(gv_le-.
Cc4"z_
¢% goliol.
c. I,c_oacd.- CA.L4-¢;_Ce.x_,, _wrv_,_ i_/.e.% c'_._se,
3 <_ _P-,Nc'-_5 CsN r; ,,_ ; ¢_e.!.
4hr_qh
24.
A=
c=
I
.
_.
•
¢Y_Tt_-Vl,.c.
D: Cx.,c-t_r<
Co.,e-e.( _qta_ct)
E=
ttqrlx.v.. C_._
25.
q /3ql_
(ICo,n+-'lLf{&
iS
5o
.
\
_-_lOG
\
I 8 ! I
! I ! I
i I I 11
Temperature
(°Cl
26. Rate of increase (is constan_
27. Rate of increase
28. Temperature
i_-eate_,
less)
at base of lithosphere
29. °C,100 km:
IL'_0
30. See figure in question
is (600_1800)
O
, °C/km:
I k_
25 - only do basalt
31. Omit
32. Lithosphere
33. Reaches
34.
35.
36.
(has_
reached melting temperature
I
melting temperature
_'[_"/_,
at
and should be(_molten)
] _)
km. (Solid, partly melted)
['3 _ _ _ _1._ _sO_..
_.t70 __)
37. Foci are distributed
38 and 39. Omit
kilometers
(in a random manner,___yalong
aIm_e
material below this.
1
+
GeologicStructuresand Maps - Chapter 11 and 18
Name:
TA name or Section #
'? _CJl_
Strike and dip: Recall that three pieces of information fully define the strike and dip of a layer.
Reminders:
1) Trend of the strike line, 2) The magnitude (angle) of dip, and 3) The direction of dip
/
Yw
These data are recorded on a map by a small symbol like this" 4s-]
Folds:
Folds:
_:_i°_ -"
- _
On a map view, eroded folds will show stripes of layers
Anticlines - upside down U-shaped fold, oldest beds in middle, and limbs dip away from middle
Syncline_ - U-shaped fold, youngest beds in middle, limbs dip towards the middle
.
Plunging folds: On a map view, eroded plunging folds show U-shapes.
Plunging anticline - U-shape points in the SAME direction that the fold axis dips
Plunging synciine - U-shape points in the OP[_OS[TE direction that th_ fold axis dips
Faults:
Strike-slip fault- movement of the rock layers is mostly horizontal
Dip-slip fault - movement of rock layers is mostly vertical
Determining
the movement
In determining the movement
of faults in map view:
of faults with only a map view, there are two important principles
1. Faults always dip TOWARD
--
the hangingwall.
to remember.
Map View
2. The side with the older rock layer is the side that moved up.
,_
--r_
I
B
[
C
B
As an example in the figure to your left: Assume
_'youngest layer and layer B is the oldest.
1. Determine
layer D is the
which side of the fault is the hangingwall
and which side
C
of the fault is the footwall.
The squareson the west side of the fault areused to indicatethe directionof dip(to the
west in this case). Therefore, the hangingwall is the west side of the faultbecausethe
fault is dipping to the west.
0ld-_
_
2. Pick a spot along the fault and compare the relative ages ofthe
layers aeross the fault.
Comparingages across the fault at Z indicatesthat the west side of the faultcontains
older rocks(C) than the east side (D) andthus, the west side movedup.
Therefore,
the hangingwall
moved up. It is a REVERSE
FAULT.
|
_ -OZ
•
D
D
_x_)
|
_O'_Od_5_-X]/
]:_
Sideview of this edge
I
D
lc8
/
/
/
[
°
c
I
Exercise 1:
View
1. Determine Whether the fault in the figure to the right is a
normal or reverse fault:
B
/4"
C
The small squares along the fault point in the direction of the dip
of the fault plane (i.e. in this case the fault dips south). Assume
that B is the youngest layer and D is the oldest layer.
D
B
The fault is a:
)_,J0_f_l._
/4"
/c
/
o
Exercise 2: Use the map on the right to answer these questions. Assume that layer A is the oldest and layer D
is the youngest. Also assume that the small squares show the direction of the dip of the fault plane.
1. What direction does layer B strike on the
west side of the fault?
_,J--)
'
_-_
2. What direction does layer B dip on the
west side of the fault?
Map View
I-
30
30 C
D
30
3. What direction does the fault plane strike?
4. What direction doesthe fault plane dip?
C
01d.LS"_'_ k)
3O
5. Which side (west or east) of the fault
moved up?
' _
6. Therefore, this is a
C
fault.
7. What type of structure is depicted on the east side of the map?
Exercise 3: From lab manual-0K._.:_Z-_C.,_I.A.5.
r_3°
/
k
24. A.a.
B
__j
_--(,_
S?oungest
IOt e..e..
{9a\.Loz--oio
B
i '0
__L_
l
Exercise 4: Geologic History of the Arbuckle Mountains
Background:
It may not seem like it today, but the geology of Oklahoma is extremely rich and varied. The oldest
rocks in Oklahoma date back to the Preeambrian - more than a billion years ago. Although it presently lies in
the middle of the North American tectonic plate, Oklahoma has experienced many tectonic events. First,
Oklahoma was almost split in two from a rifting event during which large volumes of extrusive and intrusive
igneous rocks crystallized. Soon afterward, Oklahoma was the site of a large ocean. Later, two tectonic plates
collided and fused together across southeast Oklahoma. During this time mountains grew, shedding sediment
toward the west and the south. Still later, ocean water slowly migrated northward so that during the Age of the
Dinosaurs, an ocean lay approximately along the Texas-Oklahoma border. Finally, as large glaciers advanced
and retreated from Canada, Oklahoma fluctuated between a land of large rivers and a land of sand dunes. These
events can be read from knowledge of the distribution, age and orientation of the rock types - all of which are
displayed on a geologic map.
C
"i
Parts of a Geologic Map:
The Explanation (right upper part ofmap) contains information about the symbols used for the differenl
rock types, their relative ages, and the structures.
1. In most places rock units have been given a formal name, called aformation (e.g. Woodford Shale).
Each formation contains one or more specific rock types. For each formation the explanation shows a
box with: 1) the name and a description of the rock type underneath; 2) a color used to display the unit
on the map; 3) a symbol used for the unit on the map.
What is the rock type(s) making up the ADA FORMATION?
What is the symbol used on the map for the ADA FORMATION:
2. The explanation also depicts the relative ages of the different rock types of the map area. The oldest
rocks are arranged so that the bottom of the right column is the oldest rock type and the top of the left
column is the youngest unit. The explanation also shows the geologic period of each of the formations
on the right side of each column (e.g. Cambrian, Ordovician).
What is the name of the SECOND youngest unit found in the map area?
What geologic period does the CANEY SHALE represent?
3. The explanation also displays symbols usedto depict vmious geologic structures. Look them over.
What does Ibis symbol mean? _
Orientation
of beds
1) Find the town of Ravia at the southern edge of the map. Now, refer to the sequence of peach, pink,
brown and purple layers (Ocm, Owk, Ooj, Obm, Osv DsOh, and Mdsw) to the left of the town.
What is the general strike of these !ayers?
What is the general direction of dip of these layers?
2) In the far western part of the map this same sequence of layers appears.
/k)
,__*
What is the general strike of these layers?
What is the general direction of dip of these layers?
Therefore, in both cases above the layers are getting younger in what direction?
SI ,.J
W
•
lysis
3) Locate the town of DouUooRgJ__r_
(south of Lake of the Arbuckles). Now, move two squares north and
then two squares to the west. You should find the unit Osv surrounded by a purple unit and in turn by a
blue unit. This structure is a fold.
Is the oldest bed in the _or
(_u_u_
the b_ide'Xof this structure?
Therefore, is this structure an anticline or syncline?
What is the approximate compass direction of the fold axis of this fold? (Remember that the
fold axis divides the fold in two.)
4) Now, move one square farther east and find the pink unit Osv. This unit is surrounded by the units
DSOh and MDsw. Note that each of these units wrap aroun_t - forming a U-shape map pattern. Recall
that this U-shape on a map represents a plunging fold.
Is this structure an anticline or a syncline?
RnMc\ v'
What is the approximate compass direction of the fold axis of this fold.'?
NbO- %co..
In what direction is the fold plunging?
%L
Fault Analysis:
5) Find the long fault at the very east end of the Lake of the Arbuckles, right near the words "Chickasaw
Nat. Recreation Area." This fault trends to the NW-SE. Follow along this fault and find the small
triangles on the southwest side of this fault. These triangles indicate that the fault dips to the SW. The
"U" and "D" on opposite sides of the fault indicates the relative movement of the fault. "
Therefore... (circle correct answers)
oft ,ou,,
ison
The side of the fanlt that moved up is th_/NE.
Therefore this fault is _'-X4rmal_everse_ult2-x_./.
._-x
Remember, even with no little U's and D's to tell you which side of the fault moved up, you can
determine relative movement of a fanlt on a geologic map. You do this by determining which side o f
the fault contains the older unit when you compare two spots on opposite sides of the fault directly
across from each other. The side of the fault with older rocks must have moved up relative to the other
side of the fault.
6) Now, go the southern base of the map on the west side. Find the marker "R 1 E'. Then go up one
square to the fault. This fault is dipping to the SW because the small triangles are on the southwest side.
1
What is the compass direction of the strike of the fault?
' 1
k/H- 5Z .
Which side of the fault moved up--th_E_r
th_/s_de
of the fault?
Therefore, what type of fault is this?
Now that you have practiced interpreting specific structures on the geologic map, you will now try to synthesize
some of this material into a geologic history or story.
Chapter 1: The early years,
Look in the explanation at the description of the oldest rock units in the map area.
Note: there are actually four different units (pCti, pCtr, pCgr, and pCgg) that are all grouped together you can lump all four together for this discussioh. These rocks have been radiometrically dated at 1.4
billion years old ....
What is the most common rock type mentioned?
Do these types of rocks form at Earth's surface or deep in Earth's crest?
The second oldest rock type is the Carlton Rhyolite. Rocks similise
dated at 525 mil!ion years old. Does a rhyolite form at the _r
•
/_/9_._
%."_
r"
have been radiome,_cally
deep in the Earth s crust?
,..,_¢4-"
If we assume that the Carleton rhyolite lies directly on top of the granites, what must have happened
between the crystallization of the granite at 1.4 billion years ago and the eruption of the lava' forming
the Carleton Rhyolite 525 million years ago?
' qp--gc
What type of contact exists between the granite and the rhyolite?
Cix_
How much time is represented by this surface? (Use the radiometric ages given above.)
The Carlton Rhyolite is part of a major suite of ancient lava that filled-in an elongate trough which
extended across Oklahoma. These volcanic rocks mark a stage when the crust across Oklahoma was
stretched, thinned and slowly sank.
Chapter 2: The formative years.
Go back to the explanation and read throug h the descriptions of all the Units between the TIMBERED
HILLS GROUP and the CANEY SHALE. Although you will not be familiar with all the different rock
types listed, you should recognize many of the rock names.
Are most of these rocks igneous, sedimentary or metamorphic rocks?
5Cck cn-wrc
Therefore, these rocks formed at the Earth's surface, or deep in the crest?
Fossils present in the Hunton Group and the Bromide Formation indicate that the sedimentary layers
formed on the ocean floor. In fact, the whole sequence of rocks, from the TIMBERED HILLS GROUP
to the CANEY SHALE, was deposited within an ocean that covered this part of Oklahoma for over 200
million years. The thickness of these sedimentary layers is well over 11,000 ft. The ocean could not
have been 11,000 feet deep when it first covered Oklahoma, since most of the fossil organisms found in
the formations could only have lived in very shallow waters.
Therefore, what must have happened to the crust as 11,000 feet of sediments were being deposited?
What was the average rate at which these sediments accumulated?
Show your calculations.
.ooo,6S
In one location the Hunton Group (DSOh) contains a basal oolitic limestone overlain by a green shale
unit. This formation is capped by black shale named the Woodford Formation (Mdsw). The Woodford
is an important source ofoil in Oklahoma. This change in sedimentary layers suggests that the
depositional environments were changing over time from shallow-water to deeper-water environments.
Chapter 3: The turbulent years.
Virtually all of the faulting and folding that you interpreted on the geologic map occurred during a small
part of the Pennsylvanian Period. The Pennsylvanian Period represents about 35 million years.
What is the compass direction of the fold axes of all the folds that you analyzed? (see questions 3 & 4)
w-52_
Therefore, what compass direction were the forces oriented to produce the folds?
Were these forces compressional _r
extensional (pulling apart)?
What is the compass direction of most of the longest fault traces on the geologic map?
What compass direction were the forces oriented to produce these faults?
Are most of the largest faults c(c(cc(c(c_mpressionaJ)or
extensional?
(
To sum up...
...in looking at both the faults and folds, the predominant forces that created the structures are
--('/r)l'_lO_%-_
t'_l
and these forces were oriented
_k/_--'_(...
In fact these folds and faults were created when a large tectonic plate slammed into the North,
plate. As the two plates collided the crust caught on either edge of the plate crumpled as the two'p.l,ates
continued to push together. The boundary between these plates runs approximately along the
Appalachian, Ouachita, Arbuckle and Marathon Mountains (in Texas). All of these mountains were
formed about the same time from this collision of two tectonic plates.
Chapter
4: Mid-life crisis.
Just as rapidly as all the buckling and breaking of the sedimentary layers started, it stopped. The
youngest rock unit that was folded and faulted is approximately 320 million years old.
We can determine the age at which most of this folding and faulting ended by finding a location where
rock units appear to blanket or cover over the folds and faults. The folding and faulting must have
occurred before the younger sedimentary layers covered them.
Look at the far western part of the map. The _ock layers are striking NW, but end abruptly. What three
units appear to cover or blanket these NW striking layers?
What rock types arethese
three units? Did these rocks form at the Earth's surface or deep in the crust?
Therefore, as these three rock units _"ere deposited, the rock units that ttiey cover must have already
been folded and faulted and exposed at Earth's surface. The oldest of these units that blanket the folded
and faulted rock units began to form approximately 300 million years ago. The youngest rock unit that
was folded and faulted is approximately 320 million years 01d.
This same area is included in a cross section (a side view) along the line A-A' (top left part of the map
sheet). Look at the leftmost part of the cross section where the unit IPvs overlies the folded sequence.
Note that the large fold along line A-A' is an anticline.
What is the youngest unit that has been folded along thi_.__ss
cross section line?
What's the surface between the folded layers and the overlying unit IPvs called? (Hint:it's a typeof
unconformity.)
_
_1 _ _"
CC,n
f _._.._.,_i_.j_
How much time is represented by this contact? usetheagesgiven abovetomakecalculations
9_ 3
Chapter 5: Old age.
We will move to the end of the story with an analysis of the youngest unit, termed ALLUVIUM. It
represents deposits less than one million or so years old that were deposited by rivers and streams.
Does the ALLUVIUM follow the structures (folds and faults) or does it appear to cut across them?
Therefore, as the alluvium begins to blanket the Arbuckle Mountains, the area is becoming buried for
the THIRD time.
VE Final
THIS IS ONLY THE NEW INFORMATION.
THERE WAS NOT ENOUGH TIME TO
WRITE DOWN ALL THE NEW INFORMATION AND THE OLD QUESTIONS.
i.
The east African rift system:
D. Both A and B
2.The most volcanically active body in the solar system is:
C. Io
3. lben Brownings projection of a large earthquake in the new Madrid region in 1990 was
based on:
D. Tidal forces
,_4.
how many earthquakes on average occur in Oklahoma each year:
A.I to2 -
G. 3-qo
5. the largest known mass extinction event occurred 250 million years ago,_t-the
between the Permian and traisic..:
boundary
D. both B and C
6. the December 1811 new Madrid earthquake:
-felt in quebec Canada and made the Mississippi river flow backwards.
7. there is seismic activity on the moon. The largest recorded moonquakes are of about MS.
Moonquakes of this size pose a significant risk to any future named lunar outpost:
True
8. large caldera forming eruptions at Yellowstone occurred 2.1 and 1.3 million years ago and
640,000 years ago. Of these eruptions:
D. two VE1 8 and one VEI 7
9. the present and predicted future, human population of the earth exceeds the carrying
capacity of the planet:
True.
10. since the 1989 loma prieta and 1994 northridge earthquakes, how much has been spent
on seismic retrofit on bridges in California:
C. billions of dollars
11. in the short term the most probably serious threat the human race is:
C. climate change
_12. would
on be
a particular
released on
fault
thea fault
M8 earthquake
in 150 yearsoccurs
if there
every
was 150
: years the same amount of enry
B. M6 earthquake ...... _ .... L_
eA/eA,_ "L L_v_
13. the megacity with the highest risk index from natural hazards is:
D. Tokyo
14. in the build up to a volcanic eruption there is an increase in the number and size of
earthquakes and a transition from VT earthquakes to LP earthquakes
False
._
15. in a large earthquake which type of building construction is most dangerous:
D.T!mberF ....
A,
_0_
16. for the 1883 Krakatau eruption and the 1815 tambora eruption, ice comes from
Greenland and the Antarctic show that the effect of these eruptions on the atmosphere:
D. occurred in both the northern and southern hemispheres at all latitudes.
t_
17. The only official earthquake prediction in thel_,s.was made for a fault segment in the
area of:
C. Parkfield, CA.
18. the official earthquake forecast was primarily based on:
A. the regular recurrence interval for historic earthquakes on this fault segment.
19. the official earthquake forecast was:
The regular recurrence
21. of the 18 very high risk and 37 high risk volcanoes identified in the us, currently:
D. a few of the very high risk and none of the-_¢-_" high risk are monitored in real time.
22. mitigation of the adverse consequences of a large earthquake can be achieved by:
D. All A to C
I
23. the 1991 eruption of Pinatubo resulted in for 2-3 years after the eruption:
B. a significant but small decrease in average global surface temperature
24. seismicity in the new Madrid region most likely occurs because:
C. of motion on faults that bound an ancien _ri
td ge.
25. of the top ten worst natural disasters in the Us since 1900 the majority occurred over 60
years ago and this likely resulted in recent social and political complacency about natural
hazards:
True
26. one component of volcano monitoring involves measuring the flux of gases coming out
of a volcano. Which specific volcanic gas is most useful in eruption prediction?
D.SO2-
oao
u.xu i
27. climate models show that a hypothetical low latitude Yellowstone type VEI 8 super
volcano eruption would result in:
B. average temp. being cooler by 12 degrees and followed by a decade long volcanic winter
28. a catastronho
hand essentially is a bet that a natural disaster in a particular region in a
particular time frame:
B. _dll not haooen
29. the largest Oklahoma earthquake recorded was of M5.5 in 1952 the epicenter was in:
B. El Reno
30. over the last 400 million years of geological time there have been a number of mass
extinction events and flood basalt eruptions:
D. all of the flood basalt eruptions have occurred
31. the lava erupted in association with continental hotspots and continental rifts is:
C. Basalt and rhyolite.
32. the USGS has forecast that in the next thirty years in _
there is a __
probability of a M,._Z.5.
or larger earthquake:
33. the probability of a M7.5 or larger CA earthquake in the next thirly years is:
i
C. higher in southern California than in northern california
34. the effects of the 1815 tambora eruption were:
E. all of A to C
35. _
earthquake _
_e.a,x" _]o
_orvar_r-
can be obtained by:
E. none._ofthe above
36. in the new Madrid seismic zone the recurrence interval for earthquakes the magnitude of
the December 1811 event probably is the order of
of years:
C. thousands
37. statistically in the US the odds of dying in an earthquake are:
A. less than the odds of dying in a plane crash.
38. the events portrayed in the movie docudrama supervolcano are:
B. Realistic because a VEI 8 eruption at Yellowstone would produce air fall ash that would
cover much of the contiguous us and cause the catastrophic effect depicted in the movie
39. in the last 100 years we have experienced the largest eruptions that can occur, but we
have not experienced the largest earthquakes that can occur:
False
40. the sulfur dioxide released to the atmosphere during explosive volcanic eruptions are VEI
3 or larger:
E. all of the above
41. the swaying of multistory buildings in an earthquake can cause them to collapse. This is
best mitigated by:
A. Base isolation
42. the earthquake that produced the meers fault scaro in southwestern Oklahoma occurred
about __ years ago and had an estimated magnitude of:
A. 1200:7
43. the ultimate prediction dilemma at Vesuvius is that:
Y
D. the Italian authorities do have a vicil defense plan for evacuation, but it requires two
weeks advance warning of an eruption and the best that volcanologists can do is a one or two
day warning of certain eruptions
44. over the last two centuries the amount of CO2 in earths atmosphere has steadily increased
as a result of human activity. The consequence is:
C. significant atmosphere warming
45. in the rocky mountain arsenal experiment earthquakes were:
C. Induced by injection of fluid into a deep well.
. e.e.axL-V_
46: comparing since 1900 me _ worst earthquakes and eruptions globally:
C. th_worst
earthquake_ansed
more fatalities than the worst eruption
47. at which caldera in the western US did in the early 1980's increased seismicity and
ground deformation lead to the USGS issuing a notice of potential volcanic hazard:
B. Long Valley
48. which earthquake was successfully predicted in China and hundreds of thousands of lives
saved because of evacuation before the earthquake struck:
B. Haicheng, 1975
49. what is the current state of the mauna loa volcano, Hawaii:
B. deformation and seismicity..,
advisory
50. the eruption between 70,000 and 80,000 years ago that coincided with a drastic reduction
in the size of the global human population was of the Indonesian volcano:
D. Toba
51. the north American and Eurasian plates are separating across the mid atlantic ridge.
Consequently since the declaration of independence the distance between north America and
Europe has increased approximately:
C. 10 meters
52. compared to the M6.7 1994 northridge earthquake, in the M 6.9 1995
56. in the atlantic ocean there is:
D. significant
o
"
80. on a particular strike slip fault the plates in contact across the fault plane have a relative
year ant the displacement on the fault in each earthquake is 3 meters, therefore the
earthquakes on the fault is __ years:
B. 50
82. compared to a M3 earthquake, a M6 earthquake releases __
E. 27,000
times more energy: