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AP Intermediate Geography (BIEAP) study materials
AP Intermediate Geography (BIEAP) study resources

AP Intermediate Geography (BIEAP) practice questions

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Question 1Physical Geography: Earth's Interior, Geomorphology and Soils

Which seismic discontinuity separates the Earth's crust from the mantle and is marked by an abrupt increase in P-wave velocity?

  1. The Conrad discontinuity
  2. The Mohorovičić discontinuity Correct answer.
  3. The Gutenberg discontinuity
  4. The Lehmann discontinuity

Explanation

The Mohorovičić (Moho) discontinuity marks the base of the crust, where P-wave velocities jump to roughly 8 km/s as seismic waves enter denser ultramafic mantle rock. It is detected by refraction of seismic waves at this boundary.

Question 2Physical Geography: Earth's Interior, Geomorphology and Soils

S-waves cannot travel through the outer core because the outer core behaves as a liquid. Which property of S-waves directly explains this?

  1. They propagate only as compressional volume changes
  2. They travel only along the Earth's surface
  3. They are refracted only at the core-mantle boundary
  4. They require shear strength in the transmitting medium Correct answer.

Explanation

S-waves are transverse waves whose particle motion is perpendicular to propagation, so they need a medium with rigidity (shear strength). Liquids have zero shear strength, so S-waves cannot pass through the fluid outer core, producing the S-wave shadow zone.

Question 3Physical Geography: Earth's Interior, Geomorphology and Soils

The asthenosphere is best described as which of the following?

  1. A dense layer of the lower mantle beneath the transition zone
  2. A rigid layer of the upper mantle that behaves elastically
  3. The liquid portion of the outer core that generates the magnetic field
  4. A partially molten, low-rigidity zone over which lithospheric plates move Correct answer.

Explanation

The asthenosphere is a weak, partially molten zone in the upper mantle (roughly 100–350 km depth) that deforms plastically and allows rigid lithospheric plates to glide over it. It is detected by a low-velocity zone for seismic waves.

Question 4Physical Geography: Earth's Interior, Geomorphology and Soils

Which rock type forms from the cooling and solidification of molten material, either below or at the surface?

  1. Sedimentary rock
  2. Clastic rock
  3. Igneous rock Correct answer.
  4. Metamorphic rock

Explanation

Igneous rocks crystallize from magma or lava as it cools. Intrusive igneous rocks cool slowly underground (coarse grains), while extrusive rocks cool rapidly at the surface (fine grains).

Question 5Physical Geography: Earth's Interior, Geomorphology and Soils

Which soil horizon is typically the zone of maximum organic matter accumulation and darkest colour?

  1. A horizon Correct answer.
  2. R horizon
  3. B horizon
  4. C horizon

Explanation

The A horizon is the topsoil, enriched in humus from decomposed organic matter, giving it a dark colour and high biological activity. The B horizon is a subsoil accumulation zone, C is weathered parent material, and R is bedrock.

Question 6Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following landforms is produced primarily by glacial erosion?

  1. An alluvial fan
  2. A U-shaped valley Correct answer.
  3. A sand dune
  4. A meander

Explanation

Glaciers grind and pluck bedrock, widening and deepening pre-existing valleys into the characteristic U-shaped (trough) cross-section. Alluvial fans, meanders, and dunes are fluvial or aeolian features, not glacial erosional forms.

Question 7Physical Geography: Earth's Interior, Geomorphology and Soils

The principle stating that in an undisturbed sequence of sedimentary rocks, the oldest layer lies at the bottom, is known as which of the following?

  1. The principle of superposition Correct answer.
  2. The principle of uniformitarianism
  3. The principle of cross-cutting relationships
  4. The principle of lateral continuity

Explanation

The principle of superposition holds that in undeformed sedimentary sequences, each layer is younger than the one below it and older than the one above. It is fundamental to relative dating.

Question 8Physical Geography: Earth's Interior, Geomorphology and Soils

Chemical weathering by hydrolysis is most effective on which of the following minerals?

  1. Magnetite
  2. Feldspar Correct answer.
  3. Gypsum
  4. Quartz

Explanation

Hydrolysis attacks silicate minerals such as feldspar, converting them to clay minerals. Feldspar is highly susceptible because its structure reacts with water and weak acids, whereas quartz is very resistant.

Question 9Physical Geography: Earth's Interior, Geomorphology and Soils

A river flows from a steep mountain front onto a broad, flat plain, depositing sediment in a fan shape. Which landform results?

  1. A floodplain terrace
  2. A delta
  3. An alluvial fan Correct answer.
  4. A point bar

Explanation

When a stream loses gradient and velocity at the base of a mountain front, it deposits coarse sediment in a fan-shaped body called an alluvial fan. Deltas form where rivers enter standing water, not at a mountain front.

Question 10Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following best explains why the lithosphere can move over the asthenosphere?

  1. The lithosphere is completely molten
  2. The asthenosphere deforms plastically under long-term stress Correct answer.
  3. The lithosphere is denser than the asthenosphere
  4. The asthenosphere is rigid and brittle

Explanation

Although the asthenosphere is solid, it is near its melting point and deforms ductilely over geological time, allowing rigid plates to slide over it. The lithosphere is rigid and brittle, not molten.

Question 11Physical Geography: Earth's Interior, Geomorphology and Soils

A soil sample has a high proportion of fine clay particles. Which property is most likely to be characteristic of this soil?

  1. Low cation exchange capacity
  2. Rapid leaching of nutrients
  3. High water-holding capacity and plasticity Correct answer.
  4. High permeability and rapid drainage

Explanation

Clay particles are tiny with large surface area and negative charge, giving clay-rich soils high water retention, plasticity, and cation exchange capacity. Sandy soils, by contrast, drain rapidly and retain little water.

Question 12Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following is the primary process that forms a hanging valley?

  1. Wind deflates a basin in a desert
  2. A cave roof collapses
  3. A river cuts a gorge into a plateau
  4. A tributary glacier erodes less deeply than the main glacier Correct answer.

Explanation

A hanging valley forms where a smaller tributary glacier erodes its floor less deeply than the main trunk glacier, leaving the tributary valley floor elevated above the main valley floor. This creates a step or waterfall where the tributary meets the main valley.

Question 13Physical Geography: Earth's Interior, Geomorphology and Soils

In a region with high rainfall and high temperature, which soil-forming process is most likely to dominate?

  1. Calcification
  2. Salinization
  3. Podzolization
  4. Laterization Correct answer.

Explanation

Hot, wet tropical conditions promote intense leaching and the accumulation of iron and aluminium oxides, producing laterite soils. Calcification and salinization dominate in arid or semi-arid environments.

Question 14Physical Geography: Earth's Interior, Geomorphology and Soils

Which plate boundary type is associated with the formation of new oceanic crust?

  1. Intraplate zone
  2. Convergent boundary
  3. Transform boundary
  4. Divergent boundary Correct answer.

Explanation

At divergent (constructive) boundaries, plates move apart and magma rises to fill the gap, creating new oceanic crust at mid-ocean ridges. Convergent boundaries consume crust, and transform boundaries slide past each other.

Question 15Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following describes the process of isostatic adjustment?

  1. Downslope movement of saturated soil
  2. Chemical alteration of bedrock by groundwater
  3. Horizontal sliding of plates along transform faults
  4. Vertical movement of the lithosphere to maintain gravitational equilibrium Correct answer.

Explanation

Isostasy is the state of gravitational balance in which the lithosphere floats on the asthenosphere; loading or unloading (for example by ice sheets or erosion) causes vertical adjustment. This is distinct from lateral plate motion or mass wasting.

Question 16Physical Geography: Earth's Interior, Geomorphology and Soils

A seismic station records P-waves but no S-waves from a distant earthquake. What is the most likely explanation?

  1. The S-waves were blocked by the liquid outer core Correct answer.
  2. The earthquake was too shallow to generate S-waves
  3. The station is located in the P-wave shadow zone
  4. The S-waves were converted into surface waves

Explanation

S-waves cannot pass through the fluid outer core, creating an S-wave shadow zone beyond about 103° from the epicentre. A distant station may record P-waves while receiving no direct S-waves.

Question 17Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following statements about the Earth's inner core is correct?

  1. It is solid despite extremely high temperature because of immense pressure Correct answer.
  2. It lies directly beneath the crust
  3. It is composed mainly of silicate minerals
  4. It is liquid and generates the magnetic field

Explanation

The inner core is solid iron-nickel because pressure is so great that it keeps the metal solid despite temperatures above 5,000°C. The liquid outer core, not the inner core, generates the geomagnetic field.

Question 18Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following best describes the difference between weathering and erosion?

  1. Weathering occurs only in deserts; erosion only in rivers
  2. Weathering is transport; erosion is in-situ breakdown
  3. Weathering is in-situ breakdown; erosion is transport of material Correct answer.
  4. Weathering is chemical; erosion is always physical

Explanation

Weathering is the in-situ disintegration or decomposition of rock, whereas erosion involves the removal and transport of the weathered material by agents such as water, wind, or ice. They are distinct but linked processes.

Question 19Physical Geography: Earth's Interior, Geomorphology and Soils

A stream's discharge increases sharply and its velocity rises after heavy rainfall. Which change in sediment transport is most likely?

  1. A shift from erosion to deposition
  2. A decrease in bedload transport
  3. An increase in the competence to carry larger particles Correct answer.
  4. A rise in the stream's base level

Explanation

Higher velocity increases a stream's competence, allowing it to transport larger and heavier particles. Greater discharge and velocity generally promote erosion and transport rather than deposition.

Question 20Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following is the correct sequence of processes in the formation of a sedimentary rock?

  1. Deposition, melting, transport, crystallization
  2. Melting, cooling, crystallization, uplift
  3. Compaction, weathering, melting, deposition
  4. Weathering, transport, deposition, compaction and cementation Correct answer.

Explanation

Sedimentary rocks form when weathered material is transported, deposited, and then lithified by compaction and cementation. Melting and crystallization belong to the igneous rock cycle.

Question 21Physical Geography: Earth's Interior, Geomorphology and Soils

A mass of rock moves downslope along a curved, concave-up failure surface, rotating as it moves. Which type of mass movement is this?

  1. A creep
  2. A rockfall
  3. A slump Correct answer.
  4. A mudflow

Explanation

A slump is a rotational slide in which material moves along a curved failure plane, often leaving a scarp at the head. Rockfalls are free-fall of debris, mudflows are rapid fluid-like flows, and creep is very slow deformation.

Question 22Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following best explains why the ocean floor is younger near mid-ocean ridges and older near continental margins?

  1. Sediment deposition is faster near ridges
  2. Old crust is destroyed at ridges
  3. New crust forms at ridges and spreads outward over time Correct answer.
  4. Sea level is higher near ridges

Explanation

Sea-floor spreading creates new oceanic crust at mid-ocean ridges; as plates move away, the crust ages with distance from the ridge. Magnetic striping and radiometric dating confirm this age pattern.

Question 23Physical Geography: Earth's Interior, Geomorphology and Soils

A soil profile shows a strongly leached, ash-grey E horizon over a dark reddish-brown B horizon. Which soil-forming process does this most likely indicate?

  1. Salinization
  2. Gleization
  3. Laterization
  4. Podzolization Correct answer.

Explanation

Podzolization occurs in cool, humid coniferous forests: organic acids leach iron and aluminium from the E horizon, depositing them in the B horizon. This produces the ash-grey E horizon over a reddish-brown B horizon.

Question 24Physical Geography: Earth's Interior, Geomorphology and Soils

Which of the following best explains the origin of the Earth's magnetic field?

  1. Permanent magnetism of the solid inner core
  2. Convection of electrically conducting liquid iron in the outer core Correct answer.
  3. Magnetized rocks in the crust
  4. Charged particles in the atmosphere

Explanation

The geodynamo model attributes the magnetic field to convection of electrically conducting liquid iron in the outer core, coupled with the Earth's rotation. The solid inner core is too hot to retain permanent magnetism.

Question 25Physical Geography: Earth's Interior, Geomorphology and Soils

A landscape shows deeply weathered, iron-rich soils, abundant rainfall, and rapid chemical weathering. Which combination of climate and process best fits this landscape?

  1. Arid climate with salt weathering
  2. Cold and dry climate with frost shattering
  3. Temperate climate with podzolization
  4. Hot and humid climate with intense laterization Correct answer.

Explanation

Hot, humid climates accelerate chemical weathering and leaching, concentrating iron and aluminium oxides to form laterite. Frost shattering, salt weathering, and podzolization occur in colder, drier, or temperate settings respectively.

Question 26Physical Geography: Earth's Interior, Geomorphology and Soils

Which seismic discontinuity separates the Earth's crust from the mantle, marked by an abrupt increase in the velocity of P-waves and S-waves?

  1. The Mohorovičić discontinuity Correct answer.
  2. The Conrad discontinuity
  3. The Lehmann discontinuity
  4. The Gutenberg discontinuity

Explanation

The Mohorovičić discontinuity, or Moho, is the boundary between the crust and the mantle and is detected where compressional and shear wave velocities jump sharply because mantle rock is denser and more rigid than crustal rock. It lies at roughly 5–10 km depth beneath the oceans and 30–70 km beneath continents.

Question 27Physical Geography: Earth's Interior, Geomorphology and Soils

A slope of unconsolidated sand becomes saturated after prolonged rain and then fails suddenly, with the material moving downslope as a chaotic, rapidly flowing mixture of water and sediment. Which type of mass movement does this describe?

  1. Creep
  2. A rockfall
  3. A rotational slump
  4. A debris flow Correct answer.

Explanation

A debris flow is a rapid downslope movement of water-saturated, poorly sorted material in which the mass behaves as a flowing slurry rather than sliding along a single plane. Saturation reduces friction and adds weight, allowing sudden failure on moderate slopes.

Question 28Physical Geography: Earth's Interior, Geomorphology and Soils

In a soil profile developed on a well-drained, humid temperate site, which horizon is characterised by the accumulation of illuvial clay, iron oxides and aluminium oxides washed down from above?

  1. The C horizon
  2. The B horizon Correct answer.
  3. The O horizon
  4. The A horizon

Explanation

The B horizon is the zone of illuviation, where materials eluviated from overlying horizons accumulate; in humid temperate soils this often produces clay-enriched, reddish or brownish subsoil. Its position below the A and E horizons and above the weathered parent material is diagnostic.

Question 29Physical Geography: Earth's Interior, Geomorphology and Soils

A limestone plateau receives heavy rainfall, and surface streams are scarce while caves and sinkholes are common. Which set of processes best explains this landscape?

  1. Mechanical abrasion by wind-blown sand, followed by deflation of the plateau surface
  2. Frost shattering of bedrock, followed by removal of angular debris by solifluction
  3. Hydrolysis of feldspar, followed by surface sheet erosion of the resulting clay
  4. Carbonation solution along joints, followed by underground drainage through enlarged conduits Correct answer.

Explanation

Limestone is soluble in weakly acidic rainwater, so carbonation along joints widens openings into sinkholes, swallow holes and cave systems, and drainage becomes predominantly subterranean. This karst assemblage explains both the scarcity of surface streams and the abundance of caves and closed depressions.

Question 30Physical Geography: Earth's Interior, Geomorphology and Soils

Two drainage basins of equal area lie side by side; basin X has elongate, gently sloping catchments with permeable soils, while basin Y has compact, steep catchments with impermeable clay. Which comparison of their flood hydrographs is most defensible?

  1. Both basins will show identical hydrographs because catchment area is the same
  2. Basin X will show a higher peak discharge but a longer lag time than basin Y
  3. Basin Y will show a lower peak discharge and a longer lag time than basin X
  4. Basin Y will show a higher, sharper peak discharge and a shorter lag time than basin X Correct answer.

Explanation

Steep slopes and impermeable clay promote rapid overland flow, so rainfall reaches the channel quickly, producing a short lag time and a high, sharply peaked hydrograph. Gentle slopes and permeable soils in basin X encourage infiltration and slower throughflow, flattening and delaying the peak.

Question 31Climatology and Oceanography

Which instrument is used to measure the relative humidity of the air at a weather station?

  1. Barometer
  2. Hygrometer Correct answer.
  3. Rain gauge
  4. Anemometer

Explanation

A hygrometer measures the moisture content of the air, which is expressed as relative humidity. A barometer measures atmospheric pressure, an anemometer measures wind speed, and a rain gauge measures rainfall amount.

Question 32Climatology and Oceanography

The layer of the atmosphere in which almost all weather phenomena occur is the:

  1. Thermosphere
  2. Troposphere Correct answer.
  3. Stratosphere
  4. Mesosphere

Explanation

The troposphere is the lowest atmospheric layer and contains most of the water vapour and dust, so clouds and weather form there. Temperature decreases with height in this layer.

Question 33Climatology and Oceanography

Lines drawn on a map joining places of equal atmospheric pressure are called:

  1. Isobars Correct answer.
  2. Isohyets
  3. Isotherms
  4. Contours

Explanation

Isobars connect points of equal pressure and are used to identify highs, lows, and pressure gradients. Isotherms join equal temperatures, isohyets join equal rainfall, and contours join equal elevation.

Question 34Climatology and Oceanography

The apparent deflection of moving air to the right in the Northern Hemisphere is explained by:

  1. Gravity
  2. Pressure gradient force
  3. Frictional drag
  4. Coriolis effect Correct answer.

Explanation

The Coriolis effect arises from the Earth's rotation and deflects moving air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The deflection grows with latitude and wind speed.

Question 35Climatology and Oceanography

Which ocean current is a warm current flowing along the eastern coast of North America?

  1. Gulf Stream Correct answer.
  2. Canary Current
  3. Labrador Current
  4. California Current

Explanation

The Gulf Stream is a warm current that flows northward along the east coast of North America. It carries warm tropical water toward higher latitudes, moderating the climate of north-western Europe.

Question 36Climatology and Oceanography

The periodic warming of surface waters in the central and eastern equatorial Pacific is known as:

  1. The North Atlantic Oscillation
  2. La Niña
  3. The Indian Ocean Dipole
  4. El Niño Correct answer.

Explanation

El Niño is the warm phase of the El Niño–Southern Oscillation and involves weakened trade winds and warmer equatorial Pacific water. It often brings drought to parts of Australia and heavy rain to Peru.

Question 37Climatology and Oceanography

In a synoptic chart, a rapidly falling barometer most directly indicates:

  1. A rising temperature
  2. Approaching low pressure Correct answer.
  3. Clear, settled weather
  4. Approaching high pressure

Explanation

Falling pressure indicates that a low-pressure system is approaching, typically bringing cloud and precipitation. A rapid fall often signals a deepening depression and stronger winds.

Question 38Climatology and Oceanography

Which term describes the amount of water vapour present in the air expressed as a percentage of the maximum it can hold at that temperature?

  1. Specific humidity
  2. Relative humidity Correct answer.
  3. Absolute humidity
  4. Dew point

Explanation

Relative humidity compares the actual vapour content with the saturation capacity at the same temperature. It changes with temperature even when the actual vapour content stays constant.

Question 39Climatology and Oceanography

Air flowing from a high-pressure area to a low-pressure area in the Southern Hemisphere is deflected:

  1. To the right of its path
  2. To the left of its path Correct answer.
  3. Directly toward the equator
  4. Straight along the isobars

Explanation

In the Southern Hemisphere, the Coriolis effect deflects moving air to the left of its direction of motion. This produces a counter-clockwise circulation around low-pressure centres in that hemisphere.

Question 40Climatology and Oceanography

A warm, moist air mass moving over a cold ocean surface is most likely to produce:

  1. Advection fog Correct answer.
  2. Frontal fog
  3. Radiation fog
  4. Convectional rain

Explanation

Advection fog forms when warm, humid air is cooled from below as it moves over a colder surface. The cooling brings the air to its dew point and condensation produces fog.

Question 41Climatology and Oceanography

The trade winds of the Northern Hemisphere blow mainly from the:

  1. South-west
  2. North-west
  3. South-east
  4. North-east Correct answer.

Explanation

Trade winds blow from the subtropical highs toward the equatorial low, deflected to the right in the Northern Hemisphere, giving north-east trades. In the Southern Hemisphere they become the south-east trades.

Question 42Climatology and Oceanography

The Gulf Stream and the Kuroshio Current both contribute to which broad pattern of ocean circulation?

  1. Western boundary current gyres Correct answer.
  2. Equatorial counter-currents
  3. Deep thermohaline sinking
  4. Antarctic circumpolar flow

Explanation

Both are warm western boundary currents of subtropical ocean gyres, flowing poleward along the eastern margins of continents. They are intensified by the rotation of the Earth and the shape of the ocean basins.

Question 43Climatology and Oceanography

During a La Niña event, the trade winds across the equatorial Pacific typically:

  1. Strengthen and push warm water westward Correct answer.
  2. Shift to a north-south direction
  3. Weaken and reverse
  4. Stop entirely

Explanation

La Niña involves stronger-than-normal trade winds that pile warm surface water in the western Pacific and increase upwelling in the east. This usually brings wetter conditions to eastern Australia and cooler, drier weather to Peru.

Question 44Climatology and Oceanography

A station reports a dry-bulb temperature of 30 °C and a wet-bulb temperature of 22 °C. What does the difference between these readings indicate?

  1. The pressure is falling
  2. The air is close to saturation
  3. The air is relatively dry Correct answer.
  4. The wind is strong

Explanation

A large gap between dry-bulb and wet-bulb temperatures shows that evaporation is rapid, so the air is far from saturation. A small difference would indicate high relative humidity.

Question 45Climatology and Oceanography

The main reason coastal areas have a smaller annual temperature range than inland areas is that:

  1. Coastal areas receive less solar radiation
  2. The sea has a lower specific heat capacity than land
  3. Coastal areas have higher elevation
  4. The sea heats and cools more slowly than land Correct answer.

Explanation

Water has a high specific heat capacity, so the sea warms and cools slowly and moderates coastal temperatures. Land heats and cools quickly, giving continental interiors a wider range.

Question 46Climatology and Oceanography

Which cloud type is most characteristic of strong vertical convection in an unstable atmosphere?

  1. Cirrostratus
  2. Cumulonimbus Correct answer.
  3. Altostratus
  4. Stratus

Explanation

Cumulonimbus clouds grow through deep convection in unstable air and are associated with thunderstorms and heavy showers. Their great vertical extent distinguishes them from layered stratiform clouds.

Question 47Climatology and Oceanography

The thermohaline circulation of the oceans is driven primarily by differences in:

  1. Wind speed and wave height
  2. Atmospheric ozone concentration
  3. Temperature and salinity Correct answer.
  4. Tidal range and lunar position

Explanation

Thermohaline circulation is driven by density differences produced by temperature and salinity, causing cold, salty water to sink in high latitudes. This deep circulation is distinct from wind-driven surface currents.

Question 48Climatology and Oceanography

A cyclone in the Northern Hemisphere shows converging winds spiralling inward. Which surface pressure pattern would produce this?

  1. A col between two highs
  2. A straight, widely spaced isobar field
  3. A closed high-pressure centre
  4. A closed low-pressure centre Correct answer.

Explanation

Air spirals inward and upward around a low-pressure centre, producing convergence and rising air. In the Northern Hemisphere this inward spiral is counter-clockwise.

Question 49Climatology and Oceanography

The rain shadow effect on the leeward side of a mountain range occurs mainly because rising air on the windward side has already:

  1. Lost most of its moisture as it cooled Correct answer.
  2. Been deflected by the Coriolis effect
  3. Warmed by compression before rising
  4. Gained moisture from the mountain surface

Explanation

Air forced to rise on the windward slope cools and its water vapour condenses, releasing precipitation. Once over the crest, the now-drier air descends and warms, giving dry conditions on the leeward side.

Question 50Climatology and Oceanography

An ocean current flowing along a west-facing coast at about 30° latitude in the Southern Hemisphere is most likely a:

  1. Warm current flowing equatorward
  2. Cold current flowing equatorward Correct answer.
  3. Cold current flowing poleward
  4. Warm current flowing poleward

Explanation

Subtropical gyres bring cool water from higher latitudes toward the equator along the eastern sides of ocean basins, which lie against west-facing continental coasts. Examples include the Benguela and Peru currents.