GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
Name the four subsystems that constitute the Earth system. -
correct answer ✅The four components that constitute the Earth
system:
a. atmosphere: the gaseous envelope surrounding the Earth.
b. hydrosphere: the water on or close to the surface of the Earth.
c. biosphere: the organic components.
d. geosphere: the inorganic components that include rock and
other materials.
Which of the four subsystems do we concentrate on most in
physical geology? -
correct answer ✅In physical geology we concentrate on the
geosphere. Nonetheless, we will also examine how the other
components (or spheres) interact with the geosphere to explain
processes that occur on and inside Earth
What advantages does geothermal energy have over fossil fuels as
a source of electric power generation? What environmental
problems are associated with the exploitation of geothermal
energy? -
correct answer ✅As a source of electricity, geothermal energy
offers some advantages over fossil fuels because it has no emissions
such as those associated with coal, oil, or natural gas. However,
,GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
steam from the hot water often contains hydrogen sulphide gas,
which is toxic, and the hot water itself may contain metal ions in
solution such as lead and mercury, which are harmful to biological
organisms. The extraction of water for geothermal energy may also
lead to ground subsidence, although pumping the cooled water
back into the ground may circumvent this. Finally, geothermal fluids
are commonly highly corrosive.
What is the difference between travertine and sinter? -
correct answer ✅When hot water discharges from the ground, it
often has minerals crystallizing from solution as it exits. Under such
circumstances, deposits of calcite form travertine, while
precipitating silica forms sinter. The type of precipitate is
determined by the geology of the subsurface.
What are geodes? -
correct answer ✅Geodes are rock cavity infills with an exterior
that comprises layers of non-crystalline (amorphous) silica, and an
interior that is often hollow and contains well-formed crystals
projecting inwards. Geodes form when crystal growth fills in the
cavities.
How do sinkholes form? -
correct answer ✅Sinkholes are depressions on the landscape that
,GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
form when roofs of subterranean cavities collapse. Alternatively,
sinkholes can form when downward percolating groundwater
enlarges cracks in soluble rocks such as limestone, rock salt (halite),
or gypsum.
How do speleotherms form? -
correct answer ✅Speleotherms are deposits of calcite that form
from dripping water in subterranean cavities. They essentially
belong to two main categories: stalactites and stalagmites.
Stalactites are protrusions that hang from the roof of caves that
form as calcite precipitates from dripping water. They are often
found aligned with cracks in the cave ceiling. Stalagmites, on the
other hand, are conical projections that form on the cave floor as
water precipitates from dripping water. Thus, stalactites grow
downwards, while stalagmites grow upwards.
What is hard water? -
correct answer ✅Hard water describes water with a high content
of dissolved ions, particularly calcium and magnesium. The calcium
usually comes from the weathering of calcium-bearing minerals
such as calcite and dolomite. Magnesium is produced by the
weathering of minerals that contain magnesium, such as dolomite
and ferromagnesium minerals.
, GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
What is the distinction between weathering and erosion? -
correct answer ✅Weathering is the "in place" disintegration and
decomposition of unstable material at the Earth's surface; erosion
is the loosening and removal of material.
Why is artificial recharge sometimes carried out? How is this done?
-
correct answer ✅Extraction of groundwater without adequate
recharge can result in a negative water balance; that is, the water
table drops in elevation. A drop in the water table can result in a
number of other problems such as ground subsidence and
compaction. To circumvent such problems, artificial recharge can be
used to augment natural recharge processes. Water used for
artificial recharge includes flood waters and treated industrial or
domestic waste waters, which are collected and stored in specially-
designed infiltration ponds for percolating into the ground.
Alternatively, water can be pumped into the ground as opposed to
letting it infiltrate from surface ponds.
What is saltwater intrusion? -
correct answer ✅In coastal areas, freshwater usually occurs in the
ground as a distinct zone floating above a more dense saltwater
zone. Saltwater intrusion refers to a process that occurs when wells
sunk to tap freshwater close to the coast are over-pumped such
Questions & Answers (Grade A+)
Name the four subsystems that constitute the Earth system. -
correct answer ✅The four components that constitute the Earth
system:
a. atmosphere: the gaseous envelope surrounding the Earth.
b. hydrosphere: the water on or close to the surface of the Earth.
c. biosphere: the organic components.
d. geosphere: the inorganic components that include rock and
other materials.
Which of the four subsystems do we concentrate on most in
physical geology? -
correct answer ✅In physical geology we concentrate on the
geosphere. Nonetheless, we will also examine how the other
components (or spheres) interact with the geosphere to explain
processes that occur on and inside Earth
What advantages does geothermal energy have over fossil fuels as
a source of electric power generation? What environmental
problems are associated with the exploitation of geothermal
energy? -
correct answer ✅As a source of electricity, geothermal energy
offers some advantages over fossil fuels because it has no emissions
such as those associated with coal, oil, or natural gas. However,
,GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
steam from the hot water often contains hydrogen sulphide gas,
which is toxic, and the hot water itself may contain metal ions in
solution such as lead and mercury, which are harmful to biological
organisms. The extraction of water for geothermal energy may also
lead to ground subsidence, although pumping the cooled water
back into the ground may circumvent this. Finally, geothermal fluids
are commonly highly corrosive.
What is the difference between travertine and sinter? -
correct answer ✅When hot water discharges from the ground, it
often has minerals crystallizing from solution as it exits. Under such
circumstances, deposits of calcite form travertine, while
precipitating silica forms sinter. The type of precipitate is
determined by the geology of the subsurface.
What are geodes? -
correct answer ✅Geodes are rock cavity infills with an exterior
that comprises layers of non-crystalline (amorphous) silica, and an
interior that is often hollow and contains well-formed crystals
projecting inwards. Geodes form when crystal growth fills in the
cavities.
How do sinkholes form? -
correct answer ✅Sinkholes are depressions on the landscape that
,GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
form when roofs of subterranean cavities collapse. Alternatively,
sinkholes can form when downward percolating groundwater
enlarges cracks in soluble rocks such as limestone, rock salt (halite),
or gypsum.
How do speleotherms form? -
correct answer ✅Speleotherms are deposits of calcite that form
from dripping water in subterranean cavities. They essentially
belong to two main categories: stalactites and stalagmites.
Stalactites are protrusions that hang from the roof of caves that
form as calcite precipitates from dripping water. They are often
found aligned with cracks in the cave ceiling. Stalagmites, on the
other hand, are conical projections that form on the cave floor as
water precipitates from dripping water. Thus, stalactites grow
downwards, while stalagmites grow upwards.
What is hard water? -
correct answer ✅Hard water describes water with a high content
of dissolved ions, particularly calcium and magnesium. The calcium
usually comes from the weathering of calcium-bearing minerals
such as calcite and dolomite. Magnesium is produced by the
weathering of minerals that contain magnesium, such as dolomite
and ferromagnesium minerals.
, GEOLOGY 200: Midterm Exam
Questions & Answers (Grade A+)
What is the distinction between weathering and erosion? -
correct answer ✅Weathering is the "in place" disintegration and
decomposition of unstable material at the Earth's surface; erosion
is the loosening and removal of material.
Why is artificial recharge sometimes carried out? How is this done?
-
correct answer ✅Extraction of groundwater without adequate
recharge can result in a negative water balance; that is, the water
table drops in elevation. A drop in the water table can result in a
number of other problems such as ground subsidence and
compaction. To circumvent such problems, artificial recharge can be
used to augment natural recharge processes. Water used for
artificial recharge includes flood waters and treated industrial or
domestic waste waters, which are collected and stored in specially-
designed infiltration ponds for percolating into the ground.
Alternatively, water can be pumped into the ground as opposed to
letting it infiltrate from surface ponds.
What is saltwater intrusion? -
correct answer ✅In coastal areas, freshwater usually occurs in the
ground as a distinct zone floating above a more dense saltwater
zone. Saltwater intrusion refers to a process that occurs when wells
sunk to tap freshwater close to the coast are over-pumped such