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MTLE Earth and Space Science (Grades 9-12) study materials
MTLE Earth and Space Science (Grades 9-12) study resources

MTLE Earth and Space Science (Grades 9-12) practice questions

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Question 1Earth and Space Science content domain (not enumerated in source)

Which layer of Earth's interior is composed mostly of solid iron and nickel and is under the greatest pressure?

  1. The inner core Correct answer.
  2. The outer core
  3. The lower mantle
  4. The asthenosphere

Explanation

The inner core is the innermost layer and consists of iron-nickel alloy that remains solid because of extremely high pressure despite very high temperature. The outer core is liquid iron-nickel, and the mantle is dominated by silicate rock.

Question 2Earth and Space Science content domain (not enumerated in source)

A seismic station records P-waves but no S-waves from a distant earthquake. What does this most directly indicate about the material the waves passed through?

  1. The earthquake was too small to generate S-waves
  2. The station was too close to the epicenter
  3. P-waves travel slower than S-waves
  4. A liquid layer blocked the S-waves Correct answer.

Explanation

S-waves cannot propagate through liquids, so a shadow zone lacking S-waves reveals a liquid region along the path, which is the outer core. P-waves refract through liquids, so they still reach the station.

Question 3Earth and Space Science content domain (not enumerated in source)

Which process best explains the driving force behind plate motion at mid-ocean ridges?

  1. Friction between plates locking them in place
  2. Tidal forces from the Moon pulling the crust
  3. Slab pull from dense subducting lithosphere combined with ridge push Correct answer.
  4. Expansion of continental crust from heating

Explanation

Mantle convection, slab pull from cold dense subducting slabs, and ridge push from elevated topography at spreading centers together drive plate motion. Slab pull is generally considered the dominant force.

Question 4Earth and Space Science content domain (not enumerated in source)

Which type of plate boundary is associated with the formation of a continental volcanic arc such as the Andes?

  1. An oceanic-continental convergent boundary Correct answer.
  2. A divergent boundary within a continent
  3. A transform boundary between two continents
  4. A hot spot far from any boundary

Explanation

At an oceanic-continental convergent boundary, the denser oceanic plate subducts, and water released from the slab promotes melting of the mantle wedge. The resulting magma rises to form a volcanic arc on the overriding continent.

Question 5Earth and Space Science content domain (not enumerated in source)

A rock sample contains a mineral that is stable only at pressures above about 10 kbar. What can be inferred about the rock's history?

  1. It formed from evaporation of seawater
  2. It was metamorphosed by contact with magma at shallow depth
  3. It was once buried at significant depth in the crust or mantle Correct answer.
  4. It cooled rapidly at the surface

Explanation

Index minerals with high-pressure stability fields indicate that the rock equilibrated at pressures corresponding to deep burial. Pressure increases roughly with depth, so such a mineral points to a deep origin.

Question 6Earth and Space Science content domain (not enumerated in source)

Which statement correctly describes how a mineral's cleavage differs from its fracture?

  1. Cleavage is an irregular break, while fracture follows flat planes
  2. Cleavage depends on color, while fracture depends on streak
  3. Cleavage breaks along planes of weak atomic bonding, while fracture is an irregular break Correct answer.
  4. Cleavage occurs only in igneous rocks, while fracture occurs only in sedimentary rocks

Explanation

Cleavage reflects planes of weaker chemical bonds in a crystal structure, so the mineral splits along flat, repeated surfaces. Fracture is a break that does not follow such planes and may be conchoidal or uneven.

Question 7Earth and Space Science content domain (not enumerated in source)

Which rock is most likely to form when a felsic magma cools slowly deep beneath the surface?

  1. Obsidian
  2. Basalt
  3. Pumice
  4. Granite Correct answer.

Explanation

Slow cooling at depth allows large crystals to grow, producing a coarse-grained intrusive texture, and felsic composition yields abundant quartz and feldspar, which is granite. Basalt is mafic, and obsidian and pumice form from rapid cooling at the surface.

Question 8Earth and Space Science content domain (not enumerated in source)

Which feature would you expect to find in a mature, well-sorted quartz sandstone deposited far from its source?

  1. Angular grains with abundant feldspar
  2. Layered bands of iron oxide cement only
  3. Large embedded fossils of coral
  4. Well-rounded grains with little feldspar Correct answer.

Explanation

Long transport wears grains round and removes less resistant minerals such as feldspar, leaving a quartz-rich, well-sorted sand. This reflects high textural and mineralogical maturity.

Question 9Earth and Space Science content domain (not enumerated in source)

Which agent is most responsible for the formation of U-shaped valleys in mountainous regions?

  1. Wave action
  2. Glacial erosion Correct answer.
  3. Wind abrasion
  4. River downcutting

Explanation

Glaciers erode bedrock along their sides and base, widening and deepening pre-existing valleys into a U-shaped cross profile. Rivers tend to carve V-shaped valleys, and wind and waves form different landforms.

Question 10Earth and Space Science content domain (not enumerated in source)

A landscape with steep slopes, thin soil, and abundant rockfall is most likely influenced by which combination of factors?

  1. Low relief and high rainfall
  2. Slow uplift and a humid climate
  3. Flat terrain and heavy vegetation
  4. Rapid uplift and a dry climate Correct answer.

Explanation

Steep slopes and thin soils reflect fast uplift outpacing weathering and erosion, and a dry climate limits soil formation and vegetation that would stabilize slopes. Together these favor rockfall and mass wasting.

Question 11Earth and Space Science content domain (not enumerated in source)

Which process transfers the greatest amount of water from the land surface to the atmosphere?

  1. Runoff into streams
  2. Condensation in clouds
  3. Transpiration from plants Correct answer.
  4. Infiltration into groundwater

Explanation

Transpiration, together with evaporation, moves water vapor from vegetation and soil into the atmosphere and is a major component of the water cycle. Infiltration and runoff move water within or across the land rather than to the atmosphere.

Question 12Earth and Space Science content domain (not enumerated in source)

Which factor most strongly controls the rate at which groundwater flows through an aquifer?

  1. The color of the surrounding soil
  2. The depth of the water table only
  3. The temperature of the surface air
  4. The permeability and hydraulic gradient of the material Correct answer.

Explanation

Darcy's law relates flow to hydraulic conductivity (a function of permeability) and the hydraulic gradient. More permeable material and a steeper gradient both increase groundwater flow.

Question 13Earth and Space Science content domain (not enumerated in source)

What primarily drives the global pattern of surface ocean currents?

  1. Tidal forces alone
  2. The salinity of coastal beaches
  3. Underwater volcanic eruptions
  4. Prevailing winds and the Coriolis effect Correct answer.

Explanation

Surface currents are driven mainly by prevailing winds, and their direction is deflected by the Coriolis effect, producing large gyres. Density differences drive deeper thermohaline circulation.

Question 14Earth and Space Science content domain (not enumerated in source)

During a strong El Niño event, what change is typically observed in the central and eastern equatorial Pacific?

  1. Colder sea-surface temperatures and stronger trade winds
  2. Permanent reversal of the Gulf Stream
  3. Warmer sea-surface temperatures and weakened trade winds Correct answer.
  4. Complete shutdown of the thermohaline circulation

Explanation

El Niño involves weakened trade winds that reduce upwelling and allow warm surface water to spread eastward across the equatorial Pacific. This shifts rainfall patterns and affects global weather.

Question 15Earth and Space Science content domain (not enumerated in source)

Which property of the atmosphere primarily determines whether a rising air parcel will continue to rise on its own?

  1. The environmental lapse rate compared with the parcel's adiabatic rate Correct answer.
  2. The altitude of the tropopause only
  3. The color of the sky at sunset
  4. The concentration of argon in the air

Explanation

If the environmental lapse rate is steeper than the parcel's adiabatic rate, the parcel stays warmer and less dense than its surroundings and keeps rising. This conditionally or absolutely unstable condition favors convection.

Question 16Earth and Space Science content domain (not enumerated in source)

A cold front is approaching a city. Which sequence of weather is most likely?

  1. Gradual warming with clear skies
  2. Steady fog with no wind change
  3. Persistent light drizzle over many days
  4. A band of heavy showers followed by cooler, drier air Correct answer.

Explanation

At a cold front, dense cold air wedges under warm air, forcing rapid uplift that produces a narrow band of intense precipitation, often with thunderstorms. After passage, temperatures fall and humidity drops.

Question 17Earth and Space Science content domain (not enumerated in source)

Which condition is most favorable for the formation of a tornado?

  1. A shallow fog layer over a valley
  2. A strong supercell thunderstorm with rotating updrafts Correct answer.
  3. A stable high-pressure system with sinking air
  4. A stationary front with no wind shear

Explanation

Tornadoes most often form within supercells, where wind shear tilts and stretches horizontal rotation into a rotating updraft that can tighten into a funnel. Stability, calm air, and shallow fog suppress such rotation.

Question 18Earth and Space Science content domain (not enumerated in source)

Which statement best explains why Earth's seasons occur?

  1. Earth's distance from the Sun varies greatly over the year
  2. Earth's axis is tilted relative to its orbital plane Correct answer.
  3. Earth's rotation speed changes with the seasons
  4. The Sun's luminosity changes seasonally

Explanation

The 23.5-degree tilt of Earth's axis means each hemisphere receives sunlight at a different angle and for a different length of time during the year. Distance variation is small and cannot explain opposite seasons in the two hemispheres.

Question 19Earth and Space Science content domain (not enumerated in source)

What is the primary cause of the Moon's phases as seen from Earth?

  1. Variations in the Moon's distance from Earth
  2. The Moon's rotation on its axis
  3. Earth's shadow falling on the Moon each month
  4. The changing angle between the Sun, Earth, and Moon Correct answer.

Explanation

As the Moon orbits Earth, the fraction of its sunlit hemisphere facing Earth changes, producing the cycle of phases. Earth's shadow causes eclipses only occasionally, not the monthly phases.

Question 20Earth and Space Science content domain (not enumerated in source)

A star's spectrum shows strong hydrogen absorption lines shifted toward longer wavelengths. What can be concluded?

  1. The star is moving toward Earth
  2. The star has no hydrogen
  3. The star is at rest relative to Earth
  4. The star is moving away from Earth Correct answer.

Explanation

A redshift means the observed wavelengths are longer than the rest wavelengths, which occurs when the source recedes. This Doppler shift is used to measure radial velocities of stars and galaxies.

Question 21Earth and Space Science content domain (not enumerated in source)

According to the nebular hypothesis, why do the inner planets of the solar system differ in composition from the outer planets?

  1. The inner planets captured more gas because of stronger gravity
  2. High temperatures near the young Sun prevented volatile materials from condensing there Correct answer.
  3. Radioactive decay converted inner planets into rock
  4. The outer planets formed from material ejected by the Sun

Explanation

In the hot inner region of the solar nebula, only refractory materials such as metals and silicates could condense, forming rocky planets. Beyond the frost line, ices condensed as well, allowing gas giants to build large cores and capture hydrogen and helium.

Question 22Earth and Space Science content domain (not enumerated in source)

Which observation is the strongest evidence that the universe is expanding?

  1. The Moon always shows the same face to Earth
  2. Stars in the Milky Way orbit its center
  3. Distant galaxies show redshifts proportional to their distance Correct answer.
  4. The Sun emits a continuous spectrum

Explanation

Hubble's observation that recession velocity increases with distance implies that space itself is expanding. This redshift-distance relationship is a cornerstone of Big Bang cosmology.

Question 23Earth and Space Science content domain (not enumerated in source)

Why do sunspots appear darker than the surrounding photosphere?

  1. They are shadows cast by the Moon
  2. They are cooler regions with intense magnetic fields Correct answer.
  3. They are regions where hydrogen fusion has stopped
  4. They are holes in the Sun's surface

Explanation

Sunspots are regions where strong magnetic fields suppress convection, so the gas there is cooler and emits less light. They are not physical holes, and fusion occurs in the core rather than the photosphere.

Question 24Earth and Space Science content domain (not enumerated in source)

A rock formation contains a fossil assemblage of trilobites but no dinosaur fossils. What is the most reasonable interpretation?

  1. The rock formed from volcanic ash only
  2. The rock formed during the Cenozoic era
  3. The rock formed after dinosaurs became extinct
  4. The rock formed before dinosaurs existed Correct answer.

Explanation

Trilobites existed in the Paleozoic and became extinct before the Mesozoic, so their presence without dinosaurs indicates an older formation. Fossil succession reflects the relative ages of rock layers.

Question 25Earth and Space Science content domain (not enumerated in source)

Which radioactive decay scheme is most useful for dating a wooden artifact a few thousand years old?

  1. Potassium-40 decay
  2. Carbon-14 decay Correct answer.
  3. Rubidium-87 decay
  4. Uranium-238 decay

Explanation

Carbon-14 has a half-life of about 5,730 years, well matched to archaeological timescales for organic material. Longer-lived isotopes such as uranium-238, rubidium-87, and potassium-40 are better suited to dating rocks millions of years old.

Question 26Earth and Space Science content domain (not enumerated in source)

A specimen splits into smooth flat sheets that reflect light and peel along one preferred direction. Which mineral property does this best illustrate?

  1. Hardness
  2. Luster
  3. Streak
  4. Cleavage Correct answer.

Explanation

Cleavage is the tendency of a mineral to break along planes of weak atomic bonding, producing flat reflective surfaces in specific directions. The smooth repeated sheets described reflect that planar breakage rather than color, powder, or scratch resistance.

Question 27Earth and Space Science content domain (not enumerated in source)

A magma with low silica content erupts quietly as dark, fluid lava flows. Which magma composition and eruption style does this describe?

  1. Felsic magma with high viscosity
  2. Intermediate magma with explosive behavior
  3. Ultramafic magma with high gas pressure
  4. Mafic magma with low viscosity Correct answer.

Explanation

Mafic magma is silica-poor and relatively low in viscosity, so gases escape easily and eruptions tend to be effusive flows. High-silica magmas instead trap gas and erupt explosively.

Question 28Earth and Space Science content domain (not enumerated in source)

A sedimentary layer shows large angular fragments mixed with fine mud and no sorting or rounding. Which transport and deposition history best fits this layer?

  1. Rapid deposition from a debris flow near the source Correct answer.
  2. Wind reworking of dry sand across a dune field
  3. Chemical precipitation in a shallow evaporating sea
  4. Long transport by a slow river far from the source

Explanation

Poor sorting with angular clasts indicates short transport and rapid deposition, as in a debris flow that freezes sediment in place. Long transport or wind reworking would round and sort the grains.

Question 29Earth and Space Science content domain (not enumerated in source)

A region has thick, deeply weathered soil and gentle slopes under heavy rainfall. Which dominant mass-wasting process should be expected there?

  1. Mudflow
  2. Rockfall
  3. Slump
  4. Creep Correct answer.

Explanation

Creep is the slow downslope movement of soil and weathered material, favored by thick soil, gentle slopes, and abundant moisture. Rapid processes such as rockfall require steep, fractured bedrock.

Question 30Earth and Space Science content domain (not enumerated in source)

A stream's discharge stays constant while its channel narrows sharply into a bedrock gorge. What happens to flow velocity in the gorge?

  1. It stays the same because discharge is unchanged
  2. It decreases because the channel is confined by bedrock walls
  3. It increases because the same discharge passes through a smaller cross section Correct answer.
  4. It drops to zero because bedrock prevents flow

Explanation

Discharge equals cross-sectional area times velocity, so with constant discharge a smaller area forces higher velocity. This is why streams erode most strongly where channels narrow.

Question 31Earth and Space Science content domain (not enumerated in source)

A confined aquifer is bounded above by an impermeable layer and is recharged in a distant highland. What happens to water in a well drilled into this aquifer?

  1. It rises above the top of the aquifer under confining pressure Correct answer.
  2. It is limited to the saturated thickness of the confining bed
  3. It flows downward until it reaches the impermeable layer
  4. It remains exactly at the water table of the overlying unconfined aquifer

Explanation

Water in a confined aquifer is under pressure from recharge at higher elevation, so a well may rise above the aquifer top, forming an artesian or potentiometric surface. The level need not match the local unconfined water table.

Question 32Earth and Space Science content domain (not enumerated in source)

A coastal city experiences high tide when the Moon is directly overhead. What is the main reason for this bulge?

  1. The Sun's gravity cancels the Moon's pull at the near side
  2. Earth's rotation flings water outward equally on all sides
  3. Atmospheric pressure pushes ocean water toward the Moon
  4. The Moon's gravitational pull exceeds Earth's at the near side, creating a differential force Correct answer.

Explanation

Tides arise from the difference in gravitational attraction across Earth's diameter, called the tidal force. The near-side bulge forms because the Moon pulls that water more strongly than it pulls Earth's center.

Question 33Earth and Space Science content domain (not enumerated in source)

A parcel of unsaturated air is forced upward over a mountain range. What happens to its temperature and relative humidity as it rises?

  1. Temperature rises and relative humidity rises
  2. Temperature falls and relative humidity rises Correct answer.
  3. Temperature falls and relative humidity falls
  4. Temperature rises and relative humidity falls

Explanation

Rising air expands into lower pressure and cools, which lowers its capacity to hold water vapor and raises relative humidity. Continued cooling can eventually reach saturation and produce clouds.

Question 34Earth and Space Science content domain (not enumerated in source)

A weather station records a sharp pressure drop, a wind shift from south to northwest, and a rapid temperature fall within an hour. Which weather feature most likely passed the station?

  1. A warm front
  2. A cold front Correct answer.
  3. A stationary front
  4. A high-pressure ridge

Explanation

A cold front is marked by a wind shift to a westerly or northwesterly direction, falling temperature, and a pressure trough followed by a rise. Warm fronts instead bring gradual warming and long periods of steady precipitation.

Question 35Earth and Space Science content domain (not enumerated in source)

A region has warm, humid surface air and strong vertical wind shear. Which severe weather hazard is most favored?

  1. Persistent radiation fog
  2. Steady drizzle from stratus clouds
  3. Supercell thunderstorms with tornado potential Correct answer.
  4. Clear calm nights with frost

Explanation

Warm humid air supplies buoyant energy, and strong vertical shear tilts and organizes storms into rotating supercells that can spawn tornadoes. The other options describe stable or weakly forced conditions.

Question 36Earth and Space Science content domain (not enumerated in source)

A sample of air at 20 degrees Celsius contains 10 grams of water vapor per kilogram and its saturation mixing ratio is 20 grams per kilogram. What is its relative humidity?

  1. 50 percent Correct answer.
  2. 20 percent
  3. 100 percent
  4. 10 percent

Explanation

Relative humidity equals actual vapor content divided by saturation content times 100, so 10 divided by 20 gives 50 percent. It measures how close the air is to saturation at that temperature.

Question 37Earth and Space Science content domain (not enumerated in source)

A rotating column of air forms over warm ocean water and moves onshore without a frontal boundary. Which term identifies this feature?

  1. Haboob
  2. Downburst
  3. Gustnado
  4. Waterspout Correct answer.

Explanation

Waterspouts are rotating columns that form over warm water, often in relatively weak convection, and can move onshore. They are not associated with the strong fronts typical of supercell tornadoes.

Question 38Earth and Space Science content domain (not enumerated in source)

A planet's orbital period is 8 years. According to Kepler's third law, what is its average distance from the Sun?

  1. 4 astronomical units Correct answer.
  2. 64 astronomical units
  3. 2 astronomical units
  4. 8 astronomical units

Explanation

Kepler's third law gives a cubed equals the square of the period in years, so 8 squared is 64, whose cube root is 4. The planet orbits at 4 astronomical units.

Question 39Earth and Space Science content domain (not enumerated in source)

A distant galaxy's light shows spectral lines shifted toward the red end compared with laboratory wavelengths. What does this indicate?

  1. The galaxy is approaching the observer
  2. The galaxy has a cooler surface temperature
  3. The galaxy has no heavy elements
  4. The galaxy is receding from the observer Correct answer.

Explanation

A redshift means the observed wavelengths are longer than emitted, consistent with the source moving away from the observer. Cosmological expansion produces this effect for distant galaxies.

Question 40Earth and Space Science content domain (not enumerated in source)

A star's luminosity is 100 times the Sun's, and its surface temperature is the same as the Sun's. How does its radius compare with the Sun's?

  1. It is 10 times the Sun's radius Correct answer.
  2. It is 1,000 times the Sun's radius
  3. It is 100 times the Sun's radius
  4. It is the same as the Sun's radius

Explanation

Luminosity varies with radius squared times temperature to the fourth power. With equal temperatures, a 100-fold luminosity requires a radius 10 times larger, since 10 squared is 100.

Question 41Earth and Space Science content domain (not enumerated in source)

A main-sequence star much more massive than the Sun ends its life in which way?

  1. Direct collapse into a black hole without any observable event
  2. Gentle ejection of a planetary nebula leaving a white dwarf
  3. Core collapse followed by a supernova explosion Correct answer.
  4. Quiet fading into a brown dwarf

Explanation

Massive stars fuse progressively heavier elements until an iron core forms and collapses, driving a supernova that can leave a neutron star or black hole. Lower-mass stars shed planetary nebulae and leave white dwarfs.

Question 42Earth and Space Science content domain (not enumerated in source)

A solar eclipse can occur only when which alignment happens?

  1. Earth passes between the Sun and the Moon near a node of its orbit
  2. The Moon reaches apogee while the Sun is at solstice
  3. Earth's axis tilts most strongly toward the Sun
  4. The Moon passes between Earth and the Sun near a node of its orbit Correct answer.

Explanation

A solar eclipse requires the new Moon to lie between Earth and the Sun and to be near an orbital node so its shadow falls on Earth. Otherwise the Moon's shadow misses Earth because of the orbit's tilt.

Question 43Earth and Space Science content domain (not enumerated in source)

A sample of rock contains equal amounts of a parent isotope and its daughter product. If the half-life is 50 million years, how old is the rock?

  1. 150 million years
  2. 25 million years
  3. 100 million years
  4. 50 million years Correct answer.

Explanation

Equal parent and daughter amounts mean one half-life has elapsed, since half the original parent has decayed. With a half-life of 50 million years, the rock is 50 million years old.

Question 44Earth and Space Science content domain (not enumerated in source)

A sequence of sedimentary layers is cut by an igneous dike that does not appear in the overlying lava flow. Which relative age statement is correct?

  1. The lava flow is older than the dike
  2. The dike and the layers formed at the same time
  3. The dike is older than all the sedimentary layers
  4. The dike is younger than the layers it cuts but older than the lava flow Correct answer.

Explanation

A crosscutting feature is younger than the rocks it cuts, so the dike postdates the sedimentary layers. Because the lava flow overlies the dike and lacks it, the flow must be younger than the dike.

Question 45Earth and Space Science content domain (not enumerated in source)

A terrane is suspected of having been accreted onto a continental margin. Which feature would most strongly support this interpretation?

  1. A batholith intruded into the continent's own crust
  2. A folded sequence continuous with the continent's sedimentary cover
  3. A river delta built from continental sediment
  4. A fault-bounded block with fossils and rock types unlike the adjacent continent Correct answer.

Explanation

Accreted terranes are fault-bounded fragments whose stratigraphy, fossils, or paleomagnetic record differ from the adjoining continent. Such mismatches indicate the block formed elsewhere and was later attached.

Question 46Earth and Space Science content domain (not enumerated in source)

At a mid-ocean ridge, new oceanic crust forms as plates diverge. Which characteristic of the seafloor supports this process?

  1. Uniform sediment thickness across the entire ocean basin
  2. Absence of earthquakes along the ridge
  3. Oldest oceanic crust located at the ridge axis
  4. Symmetrical magnetic stripe patterns on either side of the ridge Correct answer.

Explanation

Magnetic reversals recorded in new crust create matching stripes mirrored across the ridge, evidence of seafloor spreading. Crust also grows older and sediment thicker with distance from the ridge.

Question 47Earth and Space Science content domain (not enumerated in source)

A shield volcano with gentle slopes and extensive lava flows forms primarily from which process?

  1. Intrusion of granite magma beneath a plateau
  2. Explosive eruption of viscous rhyolite
  3. Alternating ash falls and pyroclastic flows
  4. Low-viscosity basaltic eruptions building broad layers Correct answer.

Explanation

Shield volcanoes grow from repeated fluid basaltic flows that spread widely before solidifying, producing broad gentle profiles. Explosive viscous magmas instead build steep composite cones.

Question 48Earth and Space Science content domain (not enumerated in source)

A region experiences frequent shallow earthquakes along a long strike-slip fault. Which plate boundary setting does this describe?

  1. A continental rift
  2. A subduction zone
  3. A hot spot
  4. A transform boundary Correct answer.

Explanation

Transform boundaries accommodate horizontal motion between plates, generating shallow crustal earthquakes along strike-slip faults. Subduction zones produce deep quakes and volcanic arcs instead.

Question 49Earth and Space Science content domain (not enumerated in source)

Which evidence best indicates that a region once had a warmer, wetter climate than today?

  1. Evaporite beds of halite and gypsum
  2. Frost-wedged boulders on the surface
  3. Fossil palms and thick coal beds in the local strata Correct answer.
  4. Paleozoic glacial till with striated clasts

Explanation

Palm fossils and coal imply abundant warmth and moisture, since palms are tropical and coal forms in wet swamp environments. Glacial till and evaporites instead indicate cold or arid conditions.

Question 50Earth and Space Science content domain (not enumerated in source)

A planet's atmosphere is dominated by carbon dioxide with little water vapor, and the planet lacks a magnetic field. Which consequence is most likely?

  1. Development of a thick ozone layer shielding the surface
  2. A strong greenhouse effect and gradual loss of atmospheric gases to space Correct answer.
  3. Permanent retention of hydrogen and helium from the solar nebula
  4. Rapid formation of liquid water oceans and a stable climate

Explanation

Carbon dioxide produces strong greenhouse warming, while a missing magnetic field allows solar wind to strip atmospheric gases over time. This combination resembles conditions on Venus.