GTEST 3
How much has global temperature increased since the mid-1970s?
0.6°C (1 °F)
What was the percentage of Arctic sea ice loss per decade between the years 1979 and 2012?
13%
Approximately how deep within the Earth is the D" layer?
2900
What is the difference between a bar and a point bar?
A bar is a small-scale channel deposit, sometimes elongated, in the middle of a braided stream; a point bar is a deposit of sediment on the inside of a meander. Both are good places to find gold nuggets.
Which best describes the difference between a delta and an alluvial fan?
A stream deposits sediments at its mouth in water in a delta; a stream deposits sediments along steep mountain slopes in an alluvial fan.
Under which of these circumstances will subduction lead to continental collision, causing it to end?
A subducting plate may carry a low-density continent that eventually ends up at the trench. Because the continental crust is too buoyant to subduct, it blocks the subduction zone.
Which of the following statements correctly describes how stream terraces can form?
Because of the drop in base level, the river erodes downward through alluvium. A new floodplain forms, and terraces represent elevated remnants of the older floodplain.
___ is the transfer of heat by the displacement of cooler materials by hot materials
Convection
The source of heat that produces deep mantle plumes is believed to be located at the blank_______________ .
D layer
What three factors cause Earth's magnetic field?
Earth's rotation and spiral flow in the iron-rich fluid of the outer core
Of the spreading centers listed, which one is spreading the most quickly, does not have a rift valley, has smooth topography, and exhibits an elevated ridge crest known as swells?
East Pacific Rise
Which of the following statements concerning unconfined aquifers in coastal areas is correct?
Encroachment of salt water in the aquifer will rise if the water table is lowered by pumping.
Which one of the following is not a speleothem?
Geyserite
How does the amount of human-induced aerosols compare with the amount from natural sources?
Human-induced aerosols equal the amount of natural aerosols.
Where in the world would we go to find a mantle plume and a rift zone in the same area that caused troublesome volcanism in 2010?
Iceland
The greatest change in the velocity of P waves occurs at the blank_______________ boundary. SHOW HINT outer core;inner core lithosphere;upper mantle mantle;outer core crust;mantle
mantle;outer core
Where do rocks that are 180 million years old or younger, are very dense, and consist of gabbro and basalt form? SHOW HINT in subaerial mountain ranges under guyots under the continents at mid-oceanic ridge
mid-oceanic ridges
Which of the following best describes how much incoming solar radiation ice and snow reflect compared with ocean water?
more than the ocean
What are the components of an accretionary wedge?
mud, volcanic debris, and sediment from both the volcanic mountains and the top of the subducting slab
This question refers to the diagram of the Earth's interior below. An earthquake has occurred at the North Pole. There are seismic stations located at X, Y, and Z. After the earthquake, the seismometer at station X will record:
no direct P or S waves as it is in the shadow zone(105-140 degrees)
Which of the below is a component in the formation of fault-block mountains?
normal faults
During the Cretaceous period, the climate was among the warmest in Earth's history. Which of the following might have caused such a long period of global warmth?
oceanic lava pouring out on the floor of the western Pacific Ocean
At which type of plate boundary would Andean-type subduction zones occur?
oceanic-continental convergent
Where does most volcanic activity occur in Andean-type subduction zones?
on the continent forming the continental volcanic arcs
What is the name of the rock sequence of the ocean floor, consisting of an upper layer of deep-sea sediments and pillow lavas, a middle layer of sheeted dikes, and a lower layer of gabbro?
ophiolite complex
It is thought that convection within the blank_______________ of the rotating planet generates Earth's magnetic field
outer core
Which one of the following does not fit with the other three?
ozone
What term describes the situation when an aquitard lies above the main water table and caused a localized saturated zone?
perched water table
Which one of the following does or did not contribute to Earth's internal heat?
plate tectonics
If rising levels of carbon dioxide and increasing temperatures cause evaporation to increase, would such a reaction be labeled a positive- or negative-feedback mechanism?
positive-feedback mechanism
Based on seismic studies, which of the following statements is true of Earth's interior? SHOW HINT It has a primarily solid mantle. It has a solid inner core. Temperature increases with increasing depth. It has a liquid outer core. All of the above are true
All of the above are true
Which river has the largest discharge of any in the world?
Amazon
What mathematical relationship relates groundwater velocity, gradient, viscosity of the fluid, and permeability of the aquifer?
Darcy's Law
Why was the continental crust of Asia deformed more than India proper during the collision of the two continents?
India is a passive continental margin consisting of a thick platform of sedimentary rocks. Southeast Asia was an accreted region formed from the collision of several small crustal fragments and is still relatively "warm and weak."
What is a braided channel, and what is happening there?
It is a wide and shallow stream, usually at the ends of glaciers; it is choked with sediment, where there is not much of a slope.
For volcanic eruptions to have a profound effect on climate change, which of the following would have to happen?
Many nearly simultaneous eruptions or some of the largest continuous eruptions on the planet would have to occur.
Why is the area around Hudson Bay in northern Canada currently rising?
Melting of the glaciers made this area lighter, so it is rebounding like a bouncing ball.
The seismic boundary between the crust and the mantle is referred to as the blank_______________ . SHOW HINT shadow zone Moho Asthenosphere lithospheric mantle transition zone
Moho
Why are mid-oceanic ridges elevated compared to the surrounding ocean floor?
Newly formed lithosphere is hotter and therefore less dense than the surrounding rocks, so it tends to rise.
Which two of the following situations can occur at subduction zones? Choose both correct answers.
Ocean crust descends under continental crust/Ocean crust descends under another slab of ocean crust.
Which of the following would be the best place to study if you were interested in deep-ocean trenches?
Pacific Ocean
A seismic wave may change direction, without bouncing back, when crossing the boundary between two different Earth materials. This phenomenon is called blank__________ . SHOW HINT Reflection Diffraction Refraction Transversing Curvature
Refraction
How does urbanization (e.g., paving) affect runoff and infiltration in a small, previously forested drainage basin?
Runoff is rapid and infiltration decreases.
Given that we cannot see the ocean floor from an airplane, how can measurements from a satellite determine the topography of the ocean floor?
Satellites bounce microwaves off the sea surface, which has a topography that mimics that of the ocean floor.
Which of the following must result in a lower base level for river and streams?
Sea level drops; land rises and erosion increases.
Which of the following best describes the "microcontinents" idea for continental collisions? CHOOSE ALL THAT APPLY.
Smaller crustal blocks, such as inactive island arcs and larger seamounts, will not subduct, so they accrete to the continent./Crustal fragments of vastly smaller size than large continents accrete to larger continents during collision.
Many large rivers in the Colorado Plateau meander in deep, narrow canyons and have no floodplains. How could this happen?
Streams flowing in meanders cut down as the plateau rose.
Why has Niagara Falls lasted so long and cut its channel in the cliff backward 7 miles (11 kilometers)?
The Lockport Dolostone is a resistant rock unit that covers a wide zone between Lake Erie and Lake Ontario, and the Niagara River has to erode the weak layers underneath before it can retreat upstream.
Which of the following best describes how geysers erupt?
The loss of water reduces pressure. With a slight reduction in pressure, water in a saturated, natural conduit suddenly boils, sending a plume of steam and hot water into the air above the vent.
Which of the following best describes the development of distributaries at the mouths of major rivers such as the Mississippi River?
The main channel divides into several smaller channels, carrying water in varying paths to base level.
How is terrane different from terrain?
The term terrane applies to crustal fragments consisting of distinct and recognizable series of rock formations that have been transported by plate tectonics. The term terrain describes the surface topography.
Obliquity
The tilt of the Earth's axis
There are important differences between global warming by greenhouse gases and aerosol cooling. Which of the following is false?
The two are evenly distributed over Earth and last long in the atmosphere.
Which of the following is a characteristic of P waves? SHOW HINT Like S waves, P waves cannot travel through all of Earth's layers. They pass through all of the layers of the Earth, refracting when they leave one state of matter and enter a different state of matter. They pass through all of the layers of the Earth, without refracting when leaving one state of matter and entering a different state of matter. They are long waves that travel through space.
They pass through all the layers of the Earth, refracting when they leave on state of matter and enter a different state of matter
Which of the following best describes a confined aquifer?
Water flows into the aquifer on one end and is trapped by aquitards above and below.
precession
Wobbling of Earth's axis
How is the rotational speed of the inner core speculated to compare with that of the rest of the planet?
a century or more faster
What geologic phenomenon causes South Africa to be elevated by as much as 1500 meters (4950 feet)?
a hot, large superplume in the mantle
Which of the following best describes a water gap?
a steep-walled notch cut through a tectonic structure, usually a ridge of tilted rock
How much has the sea level risen annually between 1993 and 2012?
about 0.1 (one-tenth) of an inch (3 mm)
Which process describes how a stream cuts a channel into bedrock by constantly hitting the bedrock with the sediment it carries?
abrasion
Which of the following statements is true of S waves? They travel more slowly than P waves. They cannot travel through gases. They cannot travel through liquids. They reflect off the outer core. They can travel through solids. All of the above are true.
all of the above
Where does seafloor spreading occur?
along the crests of mid-ocean ridges
What are permeable layers of rock, such as layers of sand or gravel that freely transmit groundwater, called?
aquifers
Of the given answers, which is Earth's weakest layer? SHOW HINT inner core troposphere Moho asthenosphere Lithosphere
asthenosphere
Where are most caverns created?
at or just below the water table in the zone of saturation
Of the materials listed below (with their relative levels of rigidity), which one will transmit seismic waves most rapidly? water (least rigid) mud (less rigid than water) sand (more rigid than shale) shale (less rigid than sandstone) basalt (most rigid)
basalt
Which of the following is a large igneous body of rock that results from coalescing plutons in an Andean-type margin?
batholith
Beno Gutenberg
calculated depth to core boundary at 2900 kilometers
eccentricity
changes in the shape of Earth's orbit
region of meanders
channel roughness, discharge, channel size, and flow velocity are balanced in the center of the diagram and chart
Which of the following describes the configuration of an unconfined water table around a pumping well?
cone of depression
Which area of continental margins holds the greatest economic and political significance?
continental shelf
Inge Lehman
discovered boundary between solid inner core and liquid outer core in 1936
Richard Dixon Oldham
discovered central core of Earth in 1906 using the shadow zones of P and S waves
Andrija Mohorovicic
discovered the discontinuity between the crust and the mantle in 1909; Moho
What two characteristics do geologists use to recognize ancient continental collision zones? CHOOSE BOTH THAT APPLY.
eroded belts of rock that show the same folds and faults as those found in current collision zones/eroded rocks that show the same types of metamorphic and igneous rocks and known as ophiolites found in modern collision zones
Which of the following projected climatic changes are virtually certain to occur in the twenty-first century?
higher maximum temperatures; more hot days and heat waves over nearly all land areas
mouth
highest discharge, lowest channel slope (gradient), smoothest channel, and highest flow velocity
What force pushes groundwater between two points below the water table?
hydraulic gradient
What are the two largest uses of groundwater in the United States?
irrigation and public supply
What term refers to the fact that the crust "floats" in gravitational balance on a denser mantle?
isostasy
The heat flow is highest near mid-oceanic ridges and is moderate in continental regions because continents contain higher amounts of heat-producing _______________ .
radioactive isotopes
plate tectonics
rearranges the configuration of the continents and ocean basins, changing oceanic currents
Of the substrates listed, which would have the largest capacity to naturally remove sewage pollutants?
slightly-clayey sand
headwaters
steepest channel slope (gradient) with highest channel roughness, low discharge, and low flow velocity
Question 2:Along what type of plate boundaries are most continental mountains formed?
subduction zone
Which one of the following would not be found along an active continental margin?
submarine canyons
What term is applied where two continents collide and are welded together?
suture
At which of the listed oceanic ridge segments is the slowest spreading center?
the Mid-Indian Ridge and the Southwest Indian Ridge
What does the term orogenesis mean?
the combination of processes that produce mountain belts
Where in the ocean would one go to find thick turbidite layers?
the deep-sea fan on the continental rise
What is the circulation of Earth's water supply between the hydrosphere, atmosphere, geosphere, and biosphere called?
the hydrologic cycle
What influences the accuracy of climate models?
the reliability of the variables upon which the model is based
What is the vadose zone?
the unsaturated zone above the water table
Discharge is __________.
the volume of water flowing past a single point in a given unit of time, measured in cubic meters per second or cubic feet per second
What is the name of gravity-driven currents of dense, sediment-laden water in the ocean?
turbidity currents
What will happen when a dam and reservoir are constructed on a graded river?
upstream from the dam, the stream channel is flooded and channel downstream of the dam
sunspots
variations in the Sun's output associated with solar flares
The upper limit of the zone of saturation is called the
water table