1.
1) The San Andreas fault can best be classified as a __________ fault.
Correct Answer
C. Transform (strike-flip)
Explanation
The San Andreas fault is best classified as a transform (strike-flip) fault because it is a boundary between two tectonic plates that are sliding past each other horizontally. This type of fault is characterized by lateral movement and the release of energy in the form of earthquakes. The term "strike-flip" refers to the fact that the fault line changes direction at certain points, causing a shift in the orientation of the rocks on either side of the fault.
2.
The location inside the Earth where an earthquake originates is termed the ____________.
Correct Answer
A. Focus
Explanation
The focus is the correct answer because it refers to the specific location inside the Earth where an earthquake originates. It is the point where the seismic energy is released and the rocks break, causing the earthquake. The focus is usually located underground and can vary in depth, depending on the type of earthquake. The term "focus" is commonly used in seismology to describe this specific point of origin for earthquakes.
3.
The correct term for a marine wave caused by volcanic or earthquake activity is a ________.
Correct Answer
D. Tsunami
Explanation
A tsunami is a marine wave caused by volcanic or earthquake activity. Unlike hurricanes or storm surges, which are caused by atmospheric conditions, tsunamis are triggered by seismic events. A pingo is a dome-shaped mound of ice found in Arctic regions, and a tombolo is a sandbar that connects an island to the mainland. Therefore, the correct term for a marine wave caused by volcanic or earthquake activity is a tsunami.
4.
A major mud flow emanating from the eruption of a composite volcano is termed a(n)_______.
Correct Answer
B. Lahar
Explanation
A major mud flow that occurs during the eruption of a composite volcano is called a lahar. Lahars are formed when volcanic ash, debris, and water mix together, creating a fast-moving mixture that can flow down the slopes of the volcano and into nearby valleys or rivers. These mudflows can be extremely destructive, causing significant damage to infrastructure and posing a threat to human lives and the environment.
5.
Lava associated with composite volcanoes is ________________.
Correct Answer
A. Thick, gassy, and felsic
Explanation
Lava associated with composite volcanoes is thick, gassy, and felsic. Composite volcanoes, also known as stratovolcanoes, are characterized by their explosive eruptions. The lava that erupts from these volcanoes is high in silica content, which makes it thick and viscous. The high gas content in the lava leads to explosive eruptions. Felsic lava also tends to have a higher viscosity due to its high silica content. Therefore, the correct answer is thick, gassy, and felsic.
6.
Which of the following features may be associated with the eruption of a stratovolcano?
Correct Answer
C. A glowing avalanche of hot gases and fine ash
Explanation
A glowing avalanche of hot gases and fine ash may be associated with the eruption of a stratovolcano. This is because stratovolcanoes are known for their explosive eruptions, which can produce pyroclastic flows. These flows consist of hot gases, volcanic ash, and other volcanic materials that move rapidly down the slopes of the volcano, often glowing due to the high temperature. This phenomenon poses a significant hazard to surrounding areas as it can cause widespread destruction and loss of life.
7.
Another term for stratovolcano is a ______________.
Correct Answer
A. Composite cone
Explanation
A stratovolcano, also known as a composite cone, is a type of volcano characterized by its steep sides and alternating layers of lava flows and pyroclastic materials. These volcanoes are typically large and explosive, with eruptions that can be highly destructive. The term "composite cone" refers to the composite nature of these volcanoes, which are built up over time by multiple eruptions. This term is used to describe the cone shape of the volcano, formed by the accumulation of different types of volcanic materials.
8.
Crater Lake in Oregon is an example which type of volcanic feature?
Correct Answer
C. Caldera
Explanation
Crater Lake in Oregon is an example of a caldera. A caldera is a large volcanic crater that forms when a volcano collapses after a massive eruption or when the magma chamber underneath the volcano empties. In the case of Crater Lake, it was formed around 7,700 years ago when Mount Mazama erupted and collapsed, leaving behind a deep basin that eventually filled with rainwater and snowmelt, creating the stunning lake we see today.
9.
Fragments ejected from a volcano ranging in size from boulders to fine dust are collectively referred to as ____________.
Correct Answer
D. TepHra
Explanation
Tephra refers to the fragments ejected from a volcano, which can vary in size from boulders to fine dust. It is a collective term that encompasses a range of volcanic materials such as ash, lapilli, and volcanic bombs. Therefore, tephra is the correct answer to describe the fragments ejected from a volcano.
10.
Which of the following volcanoes is an example of a stratovolcano?
Correct Answer
D. Mount St. Helens
Explanation
Mount St. Helens is an example of a stratovolcano because it is a steep-sided, symmetrical cone-shaped volcano composed of layers of volcanic ash, lava, and other volcanic materials. Stratovolcanoes are known for their explosive eruptions and Mount St. Helens is famous for its catastrophic eruption in 1980, which resulted in the loss of lives and extensive damage to the surrounding area. This eruption was caused by the buildup of gas and pressure within the volcano, leading to a violent explosion and the collapse of the volcano's summit.
11.
Volcanoes associated with midoceanic ridges have lava that is ______________.
Correct Answer
E. Fluid, with little gas, and mafic
Explanation
Volcanoes associated with midoceanic ridges have lava that is fluid, meaning it has low viscosity and flows easily. This lava also contains little gas, which allows it to flow more smoothly. Additionally, the lava is mafic, which means it is rich in magnesium and iron, making it darker in color.
12.
A jetlike emission of steam and hot water where groundwater is heated by geothermal heat is referred to as a ____________.
Correct Answer
B. Geyser
Explanation
A jetlike emission of steam and hot water where groundwater is heated by geothermal heat is referred to as a geyser. Geysers occur when underground water becomes heated by geothermal energy and erupts in a powerful jet of steam and water. This phenomenon is commonly associated with volcanic areas and is a result of the combination of heat, pressure, and water underground. Geysers are distinct from hot springs, which typically have a continuous flow of hot water without the explosive eruption.
13.
Trough-like downfolds are referred to as _____________.
Correct Answer
A. Synclines
Explanation
Trough-like downfolds in geological formations are known as synclines. These are characterized by downward curving layers of rock, with the youngest layers found in the center of the fold. Synclines often form in response to compressional forces in the Earth's crust, causing the layers to fold and bend downwards.
14.
Arch-like upfolds are referred to as ________________.
Correct Answer
B. Anticlines
Explanation
Arch-like upfolds in the Earth's crust are referred to as anticlines. Anticlines are formed when rock layers are pushed together and folded, causing the outer layers to bend upwards into an arch shape. These folds often result from tectonic forces and can be found in areas of mountain building or compression. Anticlines are important in geology as they can trap and accumulate oil and gas deposits within the folds.
15.
The surface across which movement takes place in a fault is referred to as the ___________.
Correct Answer
C. Fault plane
Explanation
The correct answer is "fault plane." The fault plane is the surface where movement occurs during a fault. It is the boundary between the rocks on either side of the fault, and it can be vertical, horizontal, or at an angle. The fault plane is where the rocks slip past each other, causing earthquakes. It is an essential concept in understanding the mechanics and behavior of faults.
16.
A fault scarp results from which of the following types of faults?
Correct Answer
E. Normal
Explanation
A fault scarp is a steep slope or cliff-like feature that forms when the Earth's crust is pulled apart along a normal fault. In a normal fault, the hanging wall moves downward relative to the footwall, resulting in the formation of a fault scarp. This type of faulting is commonly associated with tensional forces that occur when the Earth's crust is stretched or extended.
17.
The Richter scale measures what characteristic of earthquakes?
Correct Answer
B. Quantity of energy released
Explanation
The Richter scale measures the quantity of energy released during an earthquake. This scale was developed by Charles F. Richter in 1935 to quantify the strength or magnitude of earthquakes. It is a logarithmic scale, meaning that each whole number increase on the scale represents a tenfold increase in the amplitude of the seismic waves and approximately 31.6 times more energy release. Therefore, the Richter scale provides a way to compare the energy released by different earthquakes and assess their relative strength.
18.
The most intense earthquake activity is associated with which of the following plate boundaries?
Correct Answer
A. Converging boundary
Explanation
Converging boundaries, also known as destructive boundaries or subduction zones, are characterized by intense earthquake activity. These boundaries occur when two tectonic plates collide and one plate is forced beneath the other into the Earth's mantle. This process, called subduction, leads to the formation of deep trenches and is often associated with volcanic activity and the release of large amounts of energy, resulting in frequent and powerful earthquakes. Therefore, the correct answer is converging boundary.
19.
The East African Rift Valley demonstrates the early stage of the ___________.
Correct Answer
A. Formation of a new ocean basin
Explanation
The East African Rift Valley demonstrates the early stage of the formation of a new ocean basin. This is because the rift valley is a divergent boundary where two tectonic plates are moving apart. As the plates separate, magma rises to fill the gap, creating new crust and eventually leading to the formation of a new ocean basin. The East African Rift Valley is an example of this process in its early stages, where the continental crust is starting to split apart and form a new ocean basin.
20.
Which of the following terms is most closely associated with the description of earthquake activity?
Correct Answer
E. Seismic
Explanation
The term "seismic" is most closely associated with the description of earthquake activity. This is because "seismic" refers to anything related to earthquakes, including the study of their occurrence, measurement of their magnitude, and analysis of their effects. It encompasses the study of seismic waves, which are the vibrations that occur during an earthquake and can be measured to determine the earthquake's characteristics. Therefore, seismic is the most appropriate term to describe earthquake activity.
21.
Frothy magma ejected under high pressure from a narrow vent is most characteristic of which type of volcano?
Correct Answer
B. Cinder cone
Explanation
A cinder cone volcano is formed when frothy magma, rich in gas, is ejected under high pressure from a narrow vent. The gas bubbles in the magma expand rapidly as it reaches the surface, creating a frothy texture. This type of volcano is typically small in size and has steep sides. Stratovolcanoes, shield volcanoes, and calderas are not typically characterized by the ejection of frothy magma under high pressure from a narrow vent.
22.
Erosion of volcanic landforms often leaves behind a table-topped plateau called a _______.
Correct Answer
A. Lava mesa
Explanation
Erosion of volcanic landforms often leaves behind a table-topped plateau called a lava mesa. This is because volcanic eruptions can create large, flat areas of hardened lava. Over time, weathering and erosion wear away the surrounding softer rock, leaving behind a mesa with a flat top and steep sides. The term "lava" refers to the volcanic origin of the mesa, while "mesa" describes its characteristic table-like shape.
23.
A circular or oval structure in which strata have been forced upward, often associated with igneous intrusions or upthrusting on deep faults, is a/an ___________.
Correct Answer
E. Dome
Explanation
A dome is a circular or oval structure where layers of rock have been pushed upward, typically due to the intrusion of igneous rocks or the uplifting of deep faults. It is a geological feature characterized by its rounded shape and upward displacement of strata.
24.
Sometimes sedimentary beds are tilted upward. When weaker layers erode, the stronger layers left behind are called _____________.
Correct Answer
C. Hogback ridges
Explanation
When sedimentary beds are tilted upward, it means that the layers of rock have been tilted or inclined. As erosion occurs, the weaker layers of rock are eroded away, leaving behind the stronger layers. These stronger layers form ridges that are known as hogback ridges. Hogback ridges are characterized by their steep, narrow, and elongated shape, which is a result of the erosion of the weaker layers.
25.
When a resistant rock type is exposed at the center of a downturned fold and the rock stands up as a ridge, which of the following features may result?
Correct Answer
A. Synclinal mountains
Explanation
When a resistant rock type is exposed at the center of a downturned fold and the rock stands up as a ridge, it forms a synclinal mountain. In this scenario, the fold has a trough-like shape with the resistant rock forming the core of the fold and standing up as a ridge. The surrounding rocks are less resistant and erode more easily, creating a mountain range that follows the shape of the fold. The other options, such as fault scarps, hogbacks, cuestas, and anticlinal valleys, do not accurately describe the features that would result from this specific geological process.
26.
The erosion of shield volcano would result in all of the following except ___________.
Correct Answer
C. A tall volcanic neck, with nothing else remaining once the volcano is extinct
Explanation
The erosion of a shield volcano would result in a newly formed volcano with a central depression, deeply eroded valley heads at the early stages of erosion, canyons that eventually develop into steep-sided amphitheaters, and radial consequent streams cutting deep canyons once the volcano is extinct. However, it would not result in a tall volcanic neck with nothing else remaining once the volcano is extinct.
27.
___________ volcanoes are formed by lavas which are highly explosive.
Correct Answer
C. Strato
Explanation
Strato volcanoes, also known as composite volcanoes, are formed by highly explosive lavas. These volcanoes are characterized by alternating layers of lava flows and pyroclastic materials, such as ash, cinders, and volcanic bombs. The explosive nature of strato volcanoes is due to the high viscosity of their lavas, which trap gases and build up pressure until they explode. This results in violent eruptions with ash clouds, pyroclastic flows, and lava flows. Shield volcanoes, on the other hand, are formed by low viscosity lavas that flow easily and do not explode.
28.
The chain of Hawaiian volcanoes were created by the motion of the ________ Plate over a __________.
Correct Answer
D. Pacific, hotspot
Explanation
The chain of Hawaiian volcanoes were created by the motion of the Pacific Plate over a hotspot. Hotspots are stationary areas of intense volcanic activity beneath the Earth's surface. As the Pacific Plate moved over the hotspot, a series of volcanic islands and seamounts were formed, resulting in the chain of Hawaiian volcanoes.
29.
One form of alternative power, _______________, is conducted to the surface by circulating groundwater.
Correct Answer
C. Geothermal energy
Explanation
Geothermal energy is the correct answer because it is a form of alternative power that is conducted to the surface by circulating groundwater. Geothermal energy utilizes the heat stored within the Earth's crust to generate electricity or heat buildings. This heat is accessed through steam vents and fumaroles, which are natural openings in the Earth's surface that release steam and gases. By harnessing this geothermal energy, we can reduce our dependence on fossil fuels and utilize a sustainable and renewable source of power.
30.
A(n) ___________ is a motion of the ground surface, ranging from a faint tremor to a wild motion capable of shaking buildings apart.
Correct Answer
B. Earthquake
Explanation
An earthquake is a motion of the ground surface that can range from a faint tremor to a wild motion capable of shaking buildings apart. It is a geological phenomenon caused by the sudden release of energy in the Earth's crust, resulting in seismic waves that cause the ground to shake. Unlike tsunamis, volcanoes, and tornadoes, earthquakes specifically refer to the shaking of the ground surface. Therefore, the correct answer is earthquake.
31.
Earthquakes can occur in locations far from plate boundaries.
Correct Answer
A. True
Explanation
Earthquakes can occur in locations far from plate boundaries due to a phenomenon known as intraplate earthquakes. These earthquakes happen within the interior of tectonic plates, rather than at their boundaries. The exact cause of intraplate earthquakes is still not fully understood, but they are believed to be caused by a combination of factors, such as stress accumulation in the crust, ancient faults reactivating, and the movement of magma beneath the surface. These earthquakes can be less frequent but can still cause significant damage and are an important area of study in seismology.
32.
The San Andreas fault is a major normal fault with the potential for severe earthquakes.
Correct Answer
B. False
Explanation
The San Andreas fault is not a major normal fault with the potential for severe earthquakes. It is actually a major strike-slip fault, where the two plates slide horizontally past each other. While the San Andreas fault is capable of producing significant earthquakes, it is not classified as a normal fault.
33.
Stratovolcanoes are formed by the emission of gassy mafic lava.
Correct Answer
B. False
Explanation
Stratovolcanoes are actually formed by the emission of viscous felsic lava. This type of lava is rich in silica and has a high viscosity, which means it is thick and does not flow easily. As a result, stratovolcanoes are characterized by steep slopes and explosive eruptions. Gassy mafic lava, on the other hand, is associated with shield volcanoes, which have gentle slopes and more fluid lava flows. Therefore, the statement that stratovolcanoes are formed by the emission of gassy mafic lava is false.
34.
Most active stratovolcanoes are located along the Pacific Ring of Fire.
Correct Answer
A. True
Explanation
The statement is true because the Pacific Ring of Fire is an area in the Pacific Ocean where a large number of tectonic plates meet. This region is known for its high volcanic and seismic activity, and it is home to many active stratovolcanoes. These volcanoes are formed by the subduction of oceanic plates beneath continental plates, creating a highly volcanic environment. Therefore, it is accurate to say that most active stratovolcanoes are located along the Pacific Ring of Fire.
35.
Transcurrent faults are also known as strike-slip faults.
Correct Answer
A. True
Explanation
Transcurrent faults, also known as strike-slip faults, occur when two blocks of rock slide horizontally past each other. In these faults, the movement is primarily horizontal, with minimal vertical displacement. This type of fault is commonly associated with transform plate boundaries, such as the San Andreas Fault in California. Therefore, the statement that transcurrent faults are also known as strike-slip faults is true.
36.
A steep cliff-like fault scarp is a common result of reverse faults.
Correct Answer
B. False
Explanation
A steep cliff-like fault scarp is actually a common result of normal faults, not reverse faults. In a normal fault, the hanging wall moves downward relative to the footwall, causing the formation of a fault scarp with a steep cliff-like appearance. Reverse faults, on the other hand, involve the hanging wall moving upward relative to the footwall, which typically results in a fault scarp with a gentler slope. Therefore, the statement is false.
37.
Hotspots occurring beneath continental crust can provide vast areas of flood basalts.
Correct Answer
A. True
Explanation
Hotspots occurring beneath continental crust can indeed provide vast areas of flood basalts. This is because hotspots are areas of intense volcanic activity where plumes of hot mantle material rise to the surface. When these plumes reach the continental crust, they can cause extensive melting of the crust, leading to the eruption of large volumes of basaltic lava. This can result in the formation of flood basalts, which are extensive, flat-lying layers of basaltic lava that can cover thousands of square kilometers. Examples of flood basalts include the Deccan Traps in India and the Columbia River Basalt Group in the United States.
38.
Compression creates anticlines and synclines.
Correct Answer
A. True
Explanation
Compression creates anticlines and synclines because it involves the squeezing or pushing together of rock layers. This compression causes the layers to fold and buckle, forming upward-arching folds called anticlines and downward-arching folds called synclines. These folds are common features in areas where tectonic forces are at work, such as mountain ranges. Therefore, the statement "Compression creates anticlines and synclines" is true.
39.
Where more easily eroded strata are exposed, denudation is rapid, making lowlands. Between them rise broad belts of hills called hogbacks.
Correct Answer
B. False
Explanation
The statement is false because it states that denudation is rapid in areas where more easily eroded strata are exposed, resulting in the formation of lowlands. However, the correct explanation is that denudation is actually slower in areas with easily eroded strata, as these materials are easily weathered and eroded away. The formation of lowlands is typically associated with the deposition of sediments rather than rapid erosion. Therefore, the statement is incorrect.
40.
A trough-like downbend of strata is an anticline, while an arch-like upbend is a syncline.
Correct Answer
B. False
Explanation
The explanation for the given correct answer is that the statement is incorrect. A trough-like downbend of strata is actually a syncline, not an anticline. Conversely, an arch-like upbend is an anticline, not a syncline.
41.
Batholiths of basalt composition are a major ingredient in the mosaic of ancient rocks comprising the continental shields.
Correct Answer
B. False
Explanation
Basalt composition batholiths are not a major ingredient in the mosaic of ancient rocks comprising the continental shields. The continental shields are primarily composed of granite and gneiss, which are different types of rocks. Basalt batholiths are more commonly found in volcanic regions and are not typically associated with continental shields. Therefore, the statement is false.
42.
The system of streams on a dissected volcano cone is a radial drainage pattern.
Correct Answer
A. True
Explanation
A radial drainage pattern refers to a system of streams that diverge from a central point, resembling the spokes of a wheel. In the context of a dissected volcano cone, the streams would follow the natural slopes and contours of the cone, flowing outward from the central vent. This is a common drainage pattern found on volcanic landforms due to the radial arrangement of ridges and valleys formed during the volcano's eruption and subsequent erosion. Therefore, the statement that the system of streams on a dissected volcano cone is a radial drainage pattern is true.
43.
Stratovolcanoes produce lava flows that initially follow valleys and are highly resistant to erosion.
Correct Answer
A. True
Explanation
Stratovolcanoes are characterized by their steep slopes and explosive eruptions. When these volcanoes erupt, they produce lava flows that tend to follow existing valleys due to gravity. These lava flows are composed of thick, viscous lava that cools and solidifies quickly, forming layers of hardened rock. These layers are highly resistant to erosion, meaning they are not easily worn away by wind, water, or other erosive forces. Therefore, the statement that stratovolcanoes produce lava flows that initially follow valleys and are highly resistant to erosion is true.
44.
Where rocks are parched into a dome, erosion produces a circular arrangement of rock layers outward from the center of the dome.
Correct Answer
A. True
Explanation
Erosion can indeed produce a circular arrangement of rock layers outward from the center of a dome. This is known as exfoliation, where the outer layers of rock gradually peel away due to weathering and erosion. As the outer layers are stripped away, the underlying layers are exposed, creating a circular pattern that radiates from the center of the dome. This process is commonly observed in granite domes, where the rock layers flake off in concentric circles, giving the appearance of a dome-shaped structure.
45.
The streams carving up a landmass are controlled to a high degree by the structure of the rock on which they act.
Correct Answer
A. True
Explanation
The explanation for the given correct answer is that the structure of the rock on which streams act plays a significant role in determining their course and behavior. Different types of rock have different levels of resistance to erosion, which can result in the formation of valleys, canyons, and other landforms. The rock structure also affects the flow of water, with softer rocks being more easily eroded and creating channels for streams to follow. Therefore, the statement that the streams carving up a landmass are controlled to a high degree by the structure of the rock is true.