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In our current understanding of the Big Bang, ____________.
the Universe is considerably older than Earth
Strong evidence that the Universe is expanding comes from the fact that the light emitted from distant galaxies appears to be ____________.
The magnetic field of Earth in the geologic past is ____________.
known to have experienced numerous polarity reversals
The continental drift hypothesis was rejected at first primarily because Wegener could not _______.
identify a mechanism capable of moving continents
The distinction between the crust and mantle is primarily on the basis of a difference in ____________; the distinction between the lithosphere and asthenosphere is primarily on the basis of a difference in ____________.
composition (rock type); degree of physical rigidity
which setting would regional metamorphism be most likely?
at great depths in the crust where two continents are colliding
Concerning relative ages of the shale and sandstone, ____________.
the sandstone must be older, according to the principle of superposition
Concerning relative ages of the granite and sandstone, ____________.
their relative ages cannot be determined from the information given
In a undisturbed sequence of sedimentary rocks, younger layers overlay older layers, according to the principle of ____________.
If the rock types and fossil contents of two sedimentary rock layers on opposite sides of a canyon are identical, then these outcrops were likely physically connected at one time and formed part of an extensive, sheet-like layer of rock. This idea summarizes the principle of ____________.
Numerical ages for boundaries between intervals of the geologic time scale primarily come from ____________, in conjunction with relative age data.
radiometric dating of igneous rocks
The number of _________ in the nucleus of an atom determines its atomic number, or position on the periodic table, while the number of _________ determines its atomic mass.
) A mineral that crystallized with 16 million atoms of a radioactive element in it will contain ____ million atoms of that element after three half-lives have passed.
The surface between a sedimentary rock and an underlying igneous or metamorphic rock is termed a(n) ____________.
The P-wave shadow zone is largely the result of __________.
refraction of P waves crossing the mantle-outer core boundary
The __________ was the most recent Pleistocene glacial episode in North America. a) Dakotan
___ -shaped valley profiles are typical of canyons and valleys eroded by alpine or mountain glaciers.
Which one of the following statements is correct?
Sea level drops when water is stored in expanding ice sheets and continental glaciers.
__________ make up the suspended loads of most rivers and streams
Silt and clay-sized, detrital grains
A __________ stream pattern develops on lands underlain by tilted or folded, alternating hard and soft, sedimentary strata.
When a seismic wave while traveling trough the Earth's interior reaches its critical angle it:
reflects all of its energy up toward the surface
__________ are characteristics of downcutting streams during the early stage of valley evolution.
V-shaped river valley profiles
Where is erosion concentrated along a meandering stream?
on the outer parts of the meander loops or bends
A stream begins at an elevation of 200 meters and flows a distance of 400 kilometers to the ocean? What is the average gradient?
As the velocity of stream flow decreases, ____________.
a) flow tends to become more laminar b) the maximum flow velocity decreases c) suspended sediment starts to be deposited
Which gas is responsible for the overwhelming majority of the greenhouse effect on Earth?
As an air mass rises, it generally experiences ____________.
a decrease in temperature due to adiabatic cooling
A warm air mass may hold more moisture (water vapor) than a cold air mass of the same volume, and yet may have lower relative humidity.
Atmospheric convection of heat radiated from Earth's surface and the variety of phenomena we call weather occur within which layer of the atmosphere?
Which layer of the atmosphere is chemically stratified with lighter gasses riding above heavier ones?
Due to the Coriolis effect, air which is moving northward from the equator is deflected __________
to the east
Cold air pushes underneath warm air at cold fronts and warm air pushes underneath cold air at warm fronts.
Greenhouse gasses are best characterized as __________.
transparent to light energy while absorbing heat energy
Oxygen consists of three isotopes. During evaporation from ocean water, which isotope is
preferentially evaporated from the oceans, and thus concentrates in glacial ice?
The global temperature record from oxygen isotopes shows _________.
variations that correspond closely to the timing of Milankovitch cycles
What is the best explanation for the saw-tooth pattern of the otherwise steadily increasing atmospheric CO2 concentration?
seasonal changes in northern hemisphere CO2 emissions
Explain, in one BRIEF sentence, why the Coriolis effect (force) is not what determines which way water rotates as it drains out of your sink or toilet.
There is too little difference in the rotational velocity of the Earth from one side of the sink or toilet to the other side for this to play any significant part in the draining of water.
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