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ESS 101 Midterm Exam QUESTIONS AND CORRECT
DETAILED SOLUTIONS LATEST UPDATED VERSION
JUST RELEASED
Question: What mechanism have geologists proposed to explain the uplift of the Colorado
Plateau and the rifting of
Nevada and Utah? - CORRECT ANSWER✔✔a spreading ridge was subducted under California
and is now upwelling beneath the Basin and Range
Question: Transform plate boundaries are typically associated with ___________. - CORRECT
ANSWER✔✔divergent margins where the rate of spreading is different along segments of the
spreading ridge
Question: The cause of volcanism observed in the Cascades is similar to that of ________. -
CORRECT ANSWER✔✔the Phillipines
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Question: A shield volcano has a lower slope angle than a strato (composite) volcano because
________. - CORRECT ANSWER✔✔its basaltic lava flows have lower viscosities than the
andesitic flows of strato volcanoes
Question: What is the significance of the change in direction of the Hawaiian Island and the
Emperor Seamount chains? - CORRECT ANSWER✔✔the tectonic plate on which both island
chains sit changed directions
Question: Which tectonic margin would tend to have only shallow focused earthquakes? -
CORRECT ANSWER✔✔Divergent and Transform
Question: Basaltic composition magma can form ____________. - CORRECT ANSWER✔✔at sea
floor spreading zones
AND at continental rift zones
AND above hotspots
AND back arc spreading basins
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Question: P-waves ___________ as they travel through the outer core - CORRECT
ANSWER✔✔decelerate
Question: How can we best explain the fact that the inner and outer cores are both composed
of metallic iron and nickel yet the outer core is liquid and the inner core solid? - CORRECT
ANSWER✔✔the melting temperature for iron-nickel is lower than the geothermal gradient
temperature in the outer core.
Q:Match the magma/lava type with the appropriate geographic/tectonic setting where it likely
formed.
3. Columbia Plateau
4. Asthenosphere
5. Mount Fuji, Japan - CORRECT ANSWER✔✔3) basalt
4) periodite
5) andesite
Question: Match the magma type with the appropriate tectonic setting where it likely forms.
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1. Iceland
2. Sierra Nevada Batholith
3. Philippine Islands
4. Ural mountains
(basalt, granite, andesite, periotite, andalucite)r - CORRECT ANSWER✔✔Iceland = Basalt
Sierra Nevada Batholith = Granite
Philippine Islands = Andesite
Ural mountains= granite
Question: The Columbia Plateau is composed of rock rich in: - CORRECT ANSWER✔✔Basalt
Question: The melting temperature of granitic magma (wet melt) ______________: - CORRECT
ANSWER✔✔increases as pressure is reduced (as it rises). Therefore it solidifies as it rises and
rarely gets to surface. Dry basaltic magma has opposite effect.
ESS 101 Midterm Exam QUESTIONS AND CORRECT
DETAILED SOLUTIONS LATEST UPDATED VERSION
JUST RELEASED
Question: What mechanism have geologists proposed to explain the uplift of the Colorado
Plateau and the rifting of
Nevada and Utah? - CORRECT ANSWER✔✔a spreading ridge was subducted under California
and is now upwelling beneath the Basin and Range
Question: Transform plate boundaries are typically associated with ___________. - CORRECT
ANSWER✔✔divergent margins where the rate of spreading is different along segments of the
spreading ridge
Question: The cause of volcanism observed in the Cascades is similar to that of ________. -
CORRECT ANSWER✔✔the Phillipines
, Page 2 of 47
Question: A shield volcano has a lower slope angle than a strato (composite) volcano because
________. - CORRECT ANSWER✔✔its basaltic lava flows have lower viscosities than the
andesitic flows of strato volcanoes
Question: What is the significance of the change in direction of the Hawaiian Island and the
Emperor Seamount chains? - CORRECT ANSWER✔✔the tectonic plate on which both island
chains sit changed directions
Question: Which tectonic margin would tend to have only shallow focused earthquakes? -
CORRECT ANSWER✔✔Divergent and Transform
Question: Basaltic composition magma can form ____________. - CORRECT ANSWER✔✔at sea
floor spreading zones
AND at continental rift zones
AND above hotspots
AND back arc spreading basins
, Page 3 of 47
Question: P-waves ___________ as they travel through the outer core - CORRECT
ANSWER✔✔decelerate
Question: How can we best explain the fact that the inner and outer cores are both composed
of metallic iron and nickel yet the outer core is liquid and the inner core solid? - CORRECT
ANSWER✔✔the melting temperature for iron-nickel is lower than the geothermal gradient
temperature in the outer core.
Q:Match the magma/lava type with the appropriate geographic/tectonic setting where it likely
formed.
3. Columbia Plateau
4. Asthenosphere
5. Mount Fuji, Japan - CORRECT ANSWER✔✔3) basalt
4) periodite
5) andesite
Question: Match the magma type with the appropriate tectonic setting where it likely forms.
, Page 4 of 47
1. Iceland
2. Sierra Nevada Batholith
3. Philippine Islands
4. Ural mountains
(basalt, granite, andesite, periotite, andalucite)r - CORRECT ANSWER✔✔Iceland = Basalt
Sierra Nevada Batholith = Granite
Philippine Islands = Andesite
Ural mountains= granite
Question: The Columbia Plateau is composed of rock rich in: - CORRECT ANSWER✔✔Basalt
Question: The melting temperature of granitic magma (wet melt) ______________: - CORRECT
ANSWER✔✔increases as pressure is reduced (as it rises). Therefore it solidifies as it rises and
rarely gets to surface. Dry basaltic magma has opposite effect.
