Surface Shaping Processes - Middle School Earth and Space Science

Which agent of erosion most directly forms U-shaped valleys and moraines?

Glaciers (moving ice). Ice plucks and scours rock, creating wide valleys.
Which process forms a delta at a river mouth when flowing water slows upon entering a lake or ocean?

Deposition of sediment. River velocity drops, causing sediment to accumulate in fan shape.
Which depositional landform forms where a river enters a lake or ocean and slows down?

Delta. River velocity drops, depositing sediment in fan shape.
What type of weathering occurs when water freezes in cracks and expands?

Ice wedging (freeze–thaw mechanical weathering). Water expands 9% when freezing, creating pressure that splits rock.
Identify the process: A river slows at its mouth and drops sediment to build a delta.

Deposition. River velocity decreases, causing sediment to settle out.
Which internal process forms new crust at mid-ocean ridges?

Seafloor spreading at a divergent plate boundary. Rising magma creates new oceanic crust as plates separate.
Which process forms new land by erupting lava and ash that later cools into igneous rock?

Volcanism (volcanic eruption and lava flow). Molten rock reaches surface and solidifies.
Identify the mass movement in which a block of rock slides suddenly along a flat surface.

Rockslide. Occurs along bedding planes or fractures.
Which type of erosion is most likely to carve V-shaped valleys and meanders?

Running water (river) erosion. Water cuts downward creating narrow, winding channels.
Which chemical weathering process dissolves calcite in limestone, often forming caves?

Dissolution by carbonic acid. Rainwater + CO₂ forms weak acid that reacts with calcium carbonate.
What is deposition in the context of shaping Earth's surface?

The dropping and settling of transported sediment. Occurs when transport energy decreases.
Identify the mass movement in which water-saturated soil flows downhill rapidly like a thick liquid.

Mudflow. Common after heavy rain on steep slopes.
What is abrasion in Earth surface processes?

Sediment scrapes rock, wearing it down. Like sandpaper, moving particles grind against rock surfaces.
Identify the agent of erosion that most directly forms V-shaped valleys.

Running water (streams and rivers). Water cuts narrow, sharp valleys through downcutting.
Which agent of erosion most directly forms U-shaped valleys?

Glaciers (moving ice). Ice carves wider, deeper valleys than water erosion.
Identify the surface process: a river enters a lake and drops sediment in a fan-shaped deposit.

Deposition. Velocity drops in still water, causing settling.
Which process breaks rock but does not move it: weathering or erosion?

Weathering. Weathering occurs in place; erosion involves movement.
Which type of weathering breaks rock by physical force without changing its composition?

Mechanical (physical) weathering. Breaks rock into smaller pieces but keeps the same minerals.
Identify the process: a river slows at its mouth and builds new land outward.

Deposition forming a delta. Reduced velocity causes sediment to settle in fan shape.
What term describes the movement of weathered sediment from one place to another?

Erosion. Wind, water, ice, or gravity transport weathered materials.
What is deposition as a surface-shaping process?

Dropping and settling of transported sediment in a new location. Deposition occurs when transporting agents lose energy and drop sediment.
Which geoscience process builds new land by erupting lava and ash at Earth's surface?

Volcanism. Magma reaches surface, cooling to form volcanic mountains or islands.
Which process most directly causes mass movement like landslides and mudflows?

Gravity (mass wasting). Downslope movement occurs when gravity exceeds slope stability.
Identify the surface-shaping process: a boulder becomes rounded after tumbling in a stream.

Abrasion (mechanical weathering). Tumbling wears away sharp edges through particle collisions.
Which chemical weathering process dissolves minerals when rainwater becomes weak acid?

Carbonation. CO₂ dissolves in rain forming carbonic acid that dissolves rock.
What is the name of weathering caused by plant roots or burrowing animals breaking rock apart?

Biological weathering. Living organisms physically or chemically break down rock.
Which agent of erosion most directly creates sand dunes?

Wind. Wind carries and deposits sand particles in mounds.
Which tectonic setting most commonly creates rift valleys and mid-ocean ridges?

Plate divergence. Plates pull apart, creating depressions and new ocean floor.
What is deposition in Earth surface processes?

Sediment is dropped and laid down in a new location. Occurs when transport energy decreases below carrying capacity.
Identify the process: a river slows as it enters a lake and drops sediment in a fan shape.

Deposition forming a delta. Velocity drops at river mouth, causing sediment to settle.
Which chemical weathering process dissolves limestone and can form caves and sinkholes?

Carbonation (carbonic acid dissolution). CO₂ + water forms weak acid that dissolves calcite.
Which agent of erosion most directly forms V-shaped valleys and canyons?

Running water (rivers and streams). Flowing water cuts downward faster than sideways, creating V-shape.
Which agent of erosion most directly carves V-shaped valleys and transports sediment downstream?

Running water (streams and rivers). Water cuts downward, creating steep-sided valleys.
Which process best explains frost wedging?

Mechanical weathering by ice expansion in cracks. Water freezes in cracks, expands, and splits rock apart.
Which agent of erosion most commonly sorts sediment by size into layers in rivers and deltas?

Running water. Current velocity determines which grain sizes settle out.
What is abrasion in erosion and weathering?

Sediment scraping and grinding rock surfaces. Particles act like sandpaper, wearing away surfaces.
Which process breaks rock without changing its mineral composition: mechanical or chemical weathering?

Mechanical weathering. Physical breaking preserves mineral identity, unlike chemical changes.
What is abrasion in geoscience?

Rocks scrape and grind, wearing surfaces down. Physical weathering caused by particles grinding against surfaces.
Which plate-boundary type most commonly creates volcanic island arcs?

Convergent boundary with subduction. Oceanic plate melts beneath another, creating arc volcanoes.
Which agent of erosion most commonly forms sand dunes and loess deposits in dry regions?

Wind. Carries fine particles in arid environments with little vegetation.
What is the chemical weathering process in which carbonic acid dissolves limestone to form caves?

Carbonation (dissolution of limestone). Carbonic acid reacts with calcium carbonate in limestone.
What term describes sediment being dropped and building up in a new location?

Deposition. Transported sediment settles when the carrying force weakens.
Which process is the main external source of energy that drives weathering and erosion?

Solar energy (drives the water cycle). Powers evaporation, precipitation, and surface water flow.
Identify the mass wasting event that is a slow downhill movement of soil.

Creep. Particles move imperceptibly due to freeze-thaw and wetting cycles.
What is the primary driving force that causes erosion by rivers, glaciers, and landslides to occur downhill?

Gravity. Earth's gravitational pull drives all downslope movement.
Which chemical weathering process adds oxygen to iron-bearing minerals, producing rust-colored rock?

Oxidation. Iron minerals react with oxygen, forming red-orange iron oxide.
Which type of weathering breaks rock by physical force without changing mineral composition?

Mechanical (physical) weathering. Breaks rocks through pressure, temperature changes, or ice expansion.
Identify the plate-tectonic process that creates new seafloor at mid-ocean ridges.

Seafloor spreading at a divergent boundary. Magma rises where plates pull apart, creating new crust.
What is hydrolysis in chemical weathering?

Minerals react with water to form new minerals (for example, clay). Water molecules break down feldspar into clay minerals.
Which geoscience process moves weathered sediment by water, wind, ice, or gravity?

Erosion. Transports weathered material away from its original location.
Which process most directly breaks rock into smaller pieces without changing minerals?

Mechanical (physical) weathering. Physical forces break rock without altering mineral composition.
What chemical weathering process adds oxygen to minerals such as iron, forming rust-like compounds?

Oxidation. Iron minerals react with oxygen to form iron oxide (rust).
What is carbonation in chemical weathering?

Carbonic acid dissolves minerals, especially calcite in limestone. Weak carbonic acid forms when CO₂ dissolves in rainwater.
What type of weathering breaks rock by chemical reactions that form new minerals?

Chemical weathering. Changes mineral composition through reactions like oxidation.
What type of weathering occurs when rock is broken by freezing and thawing of water in cracks?

Mechanical weathering (ice wedging). Water expands when freezing, physically splitting rocks.
Which agent of erosion most commonly forms V-shaped valleys?

Running water (streams and rivers). Rivers cut downward faster than they widen their channels.
Identify the surface-shaping process: a river slows on a floodplain and drops sediment.

Deposition. Slower water can't carry sediment, so it settles out.
What term describes the breakdown of rock into smaller pieces without moving it?

Weathering. Physical or chemical processes break rocks apart in place.
What is mass wasting (mass movement) as a surface-shaping process?

Downslope movement of rock and soil due to gravity. Gravity pulls loose material downslope without needing other transport agents.
Identify the process: A river slows as it enters a lake and drops sand, then silt, then clay.

Deposition (sorting by particle size). Slower water drops heavier particles first, then finer ones.
Identify the geologic hazard that can rapidly reshape land by ground shaking.

Earthquake. Fault rupture releases energy as seismic waves that shake ground.
Which process is MOST directly driven by plate tectonics and builds mountains at convergent boundaries?

Mountain building (uplift from tectonic collision). Colliding plates compress and fold crust upward.
What is the geoscience process that drops and builds up transported sediment in a new place?

Deposition. Sediment settles when transport energy decreases.
Which mass movement is a rapid downhill flow of water-saturated soil?

Mudflow. Heavy rain saturates soil, creating flowing mud rivers.
Identify the agent of erosion that commonly forms U-shaped valleys.

Glaciers (moving ice). Ice plucks and grinds valley walls and floors wider.
Which process breaks rock as plant roots grow into cracks and widen them?

Root wedging. Growing roots exert pressure, widening existing cracks.
Which geoscience process is the movement of weathered sediment by water, wind, ice, or gravity?

Erosion. Transports particles away from their source through natural forces.
Identify the plate boundary where new oceanic crust forms and seafloor spreading occurs.

Divergent plate boundary. Plates separate, allowing magma to rise and create new ocean floor.
Identify the agent of erosion that most directly carves V-shaped valleys.

Running water (streams and rivers). Flowing water cuts downward faster than sideways.
Which glacier-deposited landform is an unsorted pile or ridge of sediment left by ice?

Moraine. Glaciers deposit mixed sediment when melting occurs.
Which agent of erosion most strongly shapes V-shaped valleys and canyons?

Running water (streams and rivers). Fast-flowing water cuts downward, creating steep-sided valleys.
Which type of weathering changes a rock's minerals into new substances?

Chemical weathering. Reactions with water, oxygen, or acids create new minerals.
What is a floodplain?

Flat area beside a river built by repeated flooding and deposition. Rivers overflow banks and deposit sediment during floods.
Which agent of erosion is most associated with sand dunes and loess deposits?

Wind. Carries fine particles in dry climates, building distinctive landforms.
Which agent of erosion forms U-shaped valleys, moraines, and can transport very large rocks?

Glaciers (moving ice). Ice carves valleys wider and carries unsorted debris.
What is frost wedging?

Ice expands in cracks and breaks rock apart. Water freezes, expands 9%, and wedges rock apart mechanically.
Which agent of erosion is most likely to form a V-shaped valley and a floodplain?

Running water (streams and rivers). Water cuts downward, creating narrow, steep-sided valleys.
What type of weathering breaks rock by physical forces without changing composition?

Mechanical (physical) weathering. Physical forces like ice wedging break rock apart.
Which agent of erosion most directly forms U-shaped valleys?

Glaciers (moving ice). Glaciers carve wider, deeper valleys than rivers due to their mass.
Which plate-tectonic process builds mountains when two continental plates collide?

Convergent collision (mountain building). Continental crust crumples and folds upward when plates collide.
What type of weathering happens when carbonic acid dissolves limestone to form caves and sinkholes?

Chemical weathering (carbonation). Weak carbonic acid reacts with calcium carbonate in limestone.
Which type of weathering changes minerals into new substances through chemical reactions?

Chemical weathering. Water, oxygen, or acids react with minerals to form new compounds.
Which process builds mountains when tectonic plates collide and compress Earth's crust?

Plate convergence (uplift). Colliding plates fold and thrust crust upward.
What is oxidation as a form of chemical weathering?

Reaction with oxygen that forms oxides (often rust) in minerals. Iron minerals react with oxygen, weakening rock structure.
Identify the process: Acid rain reacts with marble gravestones and rounds the carved letters.

Chemical weathering. Acid dissolves minerals in the stone.
Which wind-deposited landform is a mound or ridge of sand formed by wind?

Sand dune. Wind drops sand when velocity decreases, building mounds.
Which process most directly creates new land by adding lava that cools and hardens at the surface?

Volcanism (lava deposition). Molten rock erupts and solidifies into new landforms.
Which process is responsible for mass movement such as landslides and mudflows?

Gravity-driven mass wasting. Gravity pulls loose material downslope when support fails.
Which process describes water freezing in cracks and breaking rock apart?

Ice wedging (freeze-thaw weathering). Water expands 9% when freezing, exerting pressure on crack walls.
Which process forms a rift valley where a continent is pulled apart?

Divergent plate movement (rifting). Continental crust stretches and drops between normal faults.
Which mass movement is the sudden downhill movement of rock from a steep slope?

Rockfall. Gravity pulls loose rocks straight down cliff faces.
Which type of weathering occurs when rock is broken by abrasion, pressure release, or ice wedging?

Mechanical (physical) weathering. Breaks rock without changing its chemical composition.
What is the difference between weathering and erosion?

Weathering breaks rock down; erosion moves sediment. Weathering occurs in place; erosion requires movement.
Which internal process builds mountains when tectonic plates collide and compress crust?

Plate tectonics causing uplift and folding. Convergent boundaries compress and deform crust upward.
Which process forms caves and sinkholes by dissolving limestone?

Chemical weathering by carbonic acid dissolution. Weak carbonic acid from CO₂ + water dissolves carbonate rocks.
Which process describes plant roots widening cracks in rock?

Mechanical weathering by root wedging. Growing roots exert pressure, physically splitting rock.
Which agent of erosion is most responsible for carving V-shaped valleys?

Running water (streams and rivers). Flowing water cuts downward faster than sideways.
Which process builds new land by lava and ash accumulating at the surface?

Volcanism (volcanic eruption and buildup). Repeated eruptions stack layers, building volcanic mountains.
What is abrasion in geoscience?

Wearing down of rock by scraping from particles in motion. Moving particles act like sandpaper on rock surfaces.
Which type of mass movement is a slow, downhill movement of soil over time?

Creep. Gravity causes imperceptible downslope soil movement.
Which ocean-coast process is the main cause of beach erosion during storms?

Wave action (strong waves and currents). Storm waves have higher energy, removing more sediment.
Identify the surface-shaping process: limestone caves form as slightly acidic water dissolves rock.

Chemical weathering by carbonation. Carbonic acid dissolves calcite minerals in limestone.
Which agent of erosion most commonly forms sand dunes?

Wind. Wind deposits sand when velocity decreases around obstacles.
What is abrasion in weathering and erosion?

Rock surfaces are worn down by scraping from particles. Like sandpaper effect as particles collide with surfaces.
Which internal process most directly creates volcanoes at subduction zones?

Melting above a subducting plate and magma rise. Water from subducting slab lowers melting point of mantle rock.
What is the geoscience process that transports sediment by water, wind, ice, or gravity?

Erosion. Moves weathered material from one location to another.
Which tectonic process builds mountains by compressing and folding Earth's crust?

Plate convergence (compression and folding). Colliding plates buckle and uplift crust into mountain ranges.
Which tectonic process forms rift valleys by pulling Earth's crust apart?

Plate divergence (tension and rifting). Spreading centers create valleys as crust stretches and drops.
What is abrasion in the context of surface shaping?

Rocks scrape and grind, wearing surfaces down. Moving particles physically scratch and polish surfaces.
Identify the mass movement that is a sudden fall of rock from a steep slope.

Rockfall. Gravity pulls loose rocks down cliffs or steep slopes rapidly.
Identify the process in which gravity moves rock and soil downslope.

Mass movement (mass wasting). Gravity pulls loose material downhill without water transport.
What is acid rain weathering most commonly classified as?

Chemical weathering (dissolution by acids). Carbonic and sulfuric acids dissolve minerals chemically.
Identify the type of weathering that breaks rock without changing its composition.

Mechanical (physical) weathering. Physical forces split rock without altering its chemistry.
Which type of erosion is most likely to create U-shaped valleys and leave moraines?

Glacial erosion. Ice carves wide, flat-bottomed valleys and deposits till.
Identify the agent of erosion that most directly forms U-shaped valleys.

Glaciers (moving ice). Ice carves wide, rounded valleys as it flows downslope.
What is ice wedging (frost wedging)?

Freezing water expands in cracks and breaks rock apart. Water expands 9% when freezing, creating pressure that splits rock.
Identify the type of weathering when rock is broken into smaller pieces without changing minerals.

Mechanical (physical) weathering. Physical forces break rock without altering mineral composition.
Identify the type of weathering that changes a rock's minerals into new substances.

Chemical weathering. Reactions with water, oxygen, or acids alter mineral structure.
Identify the process: rocks become rounded and smaller as they collide during transport in a stream.

Mechanical weathering (abrasion). Physical grinding smooths sharp edges.
Which process creates new ocean crust at mid-ocean ridges?

Seafloor spreading. Magma rises and solidifies as plates separate at ridges.
What is mechanical (physical) weathering?

Rock is broken into smaller pieces without changing composition. Physical forces like ice or roots break rock without chemical change.
What is the geoscience process in which rock is broken into smaller pieces without being moved?

Weathering. Breaks rock in place through physical or chemical processes.
What type of weathering occurs when rock is broken without chemical change?

Mechanical (physical) weathering. Physical forces break rock without altering its composition.
Identify the process: A boulder becomes smoother and smaller as it tumbles downstream.

Mechanical weathering (abrasion). Physical grinding smooths surfaces without chemical change.
Which internal process forms new land and rock when magma erupts at the surface?

Volcanism (volcanic eruption and lava flows). Builds islands, mountains, and new seafloor.
Which chemical weathering process adds oxygen to iron-bearing minerals, forming rust?

Oxidation. Iron minerals react with oxygen, producing iron oxide (rust).
What is deposition?

Dropping and settling of transported sediment in a new location. Sediment stops moving when transport energy decreases.
Which mass movement is the sudden falling of rock from a steep slope or cliff?

Rockfall. Gravity pulls loose rock straight down from vertical faces.
What is the mechanical weathering process that scrapes rock surfaces by friction during transport?

Abrasion. Rock particles grind against surfaces like sandpaper during movement.
Which process primarily forms stalactites and stalagmites in caves?

Deposition of dissolved minerals from dripping water. Calcium carbonate precipitates from groundwater as it evaporates.
What is oxidation as a type of chemical weathering?

Reaction with oxygen that forms oxides (often rust) in minerals. Iron minerals react with oxygen, weakening rock structure.
Identify the mass movement that is a rapid flow of water-saturated sediment.

Mudflow. Heavy rain saturates soil, creating a flowing mixture downslope.
Which type of climate generally produces faster chemical weathering: warm/wet or cold/dry?

Warm and wet climate. Heat speeds reactions; moisture provides water for chemical processes.
Which chemical weathering process adds oxygen to minerals, commonly producing rust-colored rock?

Oxidation. Iron minerals react with oxygen, forming rust.
What is deposition in Earth surface processes?

Dropping and settling of transported sediment. Occurs when transport energy decreases below carrying capacity.
Identify the landform formed when wind deposits sand into mounds or ridges.

Sand dune. Wind drops sand when velocity decreases or obstacles block flow.
Identify the landform: a flat, elevated area with steep sides formed by erosion.

Mesa (or plateau if much larger). Resistant cap rock protects softer layers from erosion.
Which process most directly builds a delta where a river enters a lake or ocean: erosion or deposition?

Deposition. Rivers slow at mouths, dropping sediment to form fan-shaped deltas.
What is mechanical weathering?

Physical breakup of rock without changing its composition. Rocks break by frost wedging, root growth, or thermal expansion.
Identify the process that moves rock and soil downslope due to gravity.

Mass wasting. Gravity pulls loose material down steep slopes.
Which process shapes coastlines by wearing away rock with waves and currents?

Coastal erosion by wave action. Wave energy breaks rock and carries away fragments, reshaping shores.
What is a landslide?

Rapid downslope movement of rock and soil by gravity. Often triggered by rain, earthquakes, or steep slopes.
Which pair correctly matches process to effect: uplift builds mountains, or uplift breaks rock into sediment?

Uplift builds mountains. Tectonic forces push crust upward; weathering breaks rock into sediment.
Which agent of erosion includes ocean waves that shape beaches, sea cliffs, and barrier islands?

Waves and coastal currents. Wave energy erodes headlands and deposits sand on beaches.
What mechanical weathering process occurs when water freezes in cracks and expands?

Ice wedging (freeze–thaw). Water expands 9% when freezing, splitting rock apart.
Which process moves rock and soil downslope due to gravity, such as landslides or mudflows?

Mass wasting. Gravity pulls loose material downhill without other transport agents.
What is the chemical weathering reaction in which iron-bearing minerals combine with oxygen and form rust?

Oxidation. Iron reacts with oxygen to form iron oxide (rust).
Which process moves sediment: weathering, erosion, or deposition?

Erosion. Only erosion transports material; weathering breaks, deposition drops.
Which internal process builds mountains when tectonic plates collide?

Compression and uplift at convergent plate boundaries. Colliding plates crumple and fold crust upward.
What is the process in which sediments are dropped and build up landforms?

Deposition. Occurs when transporting energy decreases and particles settle.
What is chemical weathering?

Chemical change that alters minerals and forms new substances. Water, oxygen, or acids react with minerals to form new compounds.
Which internal process creates new land by releasing lava and ash at Earth's surface?

Volcanism (volcanic eruption). Magma reaches surface, building landforms through accumulation.
What is the mechanical weathering process in which water freezes in cracks and expands?

Ice wedging (freeze-thaw). Water expands 9% when freezing, creating pressure that splits rock.
What is tectonic uplift?

Raising of Earth's crust by tectonic forces. Plate tectonics push crust upward, creating elevated landforms.
Which agent of erosion most commonly creates U-shaped valleys?

Glaciers (ice erosion). Ice carves wide, flat-bottomed valleys as it moves.
Identify the mass wasting event: sudden, fast flow of water-saturated soil and debris downhill.

Mudflow (debris flow). Water-saturated debris flows like a thick liquid down steep slopes.
Which process causes rock to crack when water freezes and expands in fractures?

Ice wedging (freeze-thaw weathering). Water expands 9% when freezing, creating pressure.
What is erosion as a surface-shaping process?

Movement of weathered material by water, wind, ice, or gravity. Erosion transports weathered material away from its original location.
Which process forms many volcanic islands such as those in an island arc?

Subduction-related volcanism at a convergent boundary. Melting oceanic plate creates magma that erupts above.
Identify the surface-shaping process that creates volcanic landforms such as cones and lava plateaus.

Volcanism (eruption and lava deposition). Magma erupts and solidifies, building new surface features.
Which agent of erosion is most likely to form a U-shaped valley?

Glaciers (moving ice). Ice carves wide, flat-bottomed valleys as it moves.
Which type of weathering dissolves limestone by acidic water: physical or chemical?

Chemical weathering. Carbonic acid in water reacts with calcium carbonate in limestone.
Identify the surface-shaping process: a delta forms where a river enters a lake or ocean.

Deposition. River slows at mouth, dropping sediment in triangular pattern.
Which type of mass movement is a sudden fall of rock from a steep slope or cliff?

Rockfall. Gravity pulls loose rocks straight down from vertical faces.
Identify the process: Tree roots grow into cracks and pry a rock apart over time.

Mechanical weathering (root wedging). Growing roots exert pressure that splits rock mechanically.
Which process most directly transports sediment from one place to another?

Erosion. Erosion carries weathered material; deposition drops it.
Which plate boundary process forms new crust at mid-ocean ridges and can create rift valleys?

Divergent boundary spreading. Plates pull apart, allowing magma to rise and create new seafloor.
Which mass movement is the slow downhill movement of soil that tilts fences and trees?

Creep. Gravity causes imperceptible downslope movement over years.
Which chemical weathering process adds oxygen to minerals, often forming rust-colored compounds?

Oxidation. Iron minerals react with oxygen, creating rust-colored oxides.
Which agent of erosion most commonly creates V-shaped valleys and canyons?

Running water (stream or river erosion). Water cuts narrow channels by downcutting into bedrock.
Identify the type of weathering that changes a mineral into a new substance.

Chemical weathering. Reactions alter mineral composition, unlike physical breaking.
Which agent of erosion most directly shapes coastlines by wave action and longshore currents?

Ocean waves and currents. Wave energy erodes rock and transports sediment along shores.
Which process most directly reduces relief by wearing down mountains over long time periods?

Weathering and erosion. Continuous breakdown and removal gradually lowers elevations.
What is the difference between weathering and erosion?

Weathering breaks rock; erosion moves sediment. Weathering occurs in place; erosion involves movement.
Which process moves rock and soil downslope mainly due to gravity, such as landslides and mudflows?

Mass movement (mass wasting). Gravity pulls loose material down steep slopes.
Which process describes water freezing in cracks and breaking rock apart?

Ice wedging (freeze–thaw). Water expands 9% when freezing, exerting pressure on rock.
Identify the process: a boulder becomes rounded and smaller as it tumbles downstream.

Abrasion during erosion by running water. Sediment particles grind against rock during transport.
Which process gradually lowers mountains and fills basins over long time periods?

Weathering, erosion, transport, and deposition. Combined processes wear down highs and fill lows over time.
What chemical weathering process dissolves minerals in rock by acidic water?

Dissolution (often by carbonic acid in water). Carbonic acid forms when CO₂ dissolves in rainwater, attacking minerals.
Which option best describes wind erosion in dry regions?

Wind lifts and sandblasts sediment, transporting it. Occurs where vegetation is sparse and wind is strong.
What is the geoscience process in which transported sediment is dropped and builds up landforms?

Deposition. Occurs when moving agents lose energy and release sediment.
Which type of erosion is most likely to form sand dunes and produce well-sorted sand?

Wind erosion. Sorts particles by size, carrying only fine grains long distances.
Which term names physical weathering caused by repeated freezing and thawing of water in cracks?

Ice wedging (freeze-thaw weathering). Water expands when frozen, widening cracks in rock.
What is the difference between weathering and erosion?

Weathering breaks rock down; erosion moves the sediment. Weathering is in-place breakdown; erosion involves movement.
Identify the surface-shaping process: a glacier pulls rocks from bedrock and deepens a valley.

Glacial erosion. Moving ice plucks bedrock and carries it away.
Which force is the main driver of all mass movement on slopes?

Gravity. Pulls material downslope on any incline.
Which process can quickly build or destroy landforms by releasing lava and ash?

Volcanic eruption. Magma reaches surface, adding or removing material rapidly.
Identify the process: a saturated hillside suddenly slides as one mass along a surface.

Landslide (slide). Water reduces friction along a failure plane, enabling movement.
What is creep in mass wasting?

Very slow downslope movement of soil. Gravity causes imperceptible movement over years.
Identify whether this is erosion or deposition: a river drops sand on the inside of a meander bend.

Deposition. River loses velocity on inner bend, dropping carried sediment.
Identify the landform made when a river deposits sediment in a fan shape at a mountain front.

Alluvial fan. Forms where steep mountain streams suddenly reach flat land.
Identify the process: A hillside collapses after heavy rain, moving soil rapidly downhill.

Mass movement (landslide). Water saturates soil, reducing friction and triggering movement.
Identify the mass wasting event: very slow downhill movement of soil that can tilt fence posts.

Creep. Freeze-thaw cycles cause imperceptible downhill soil movement over time.
What mechanical weathering process scrapes and grinds rock as sediment is carried by wind or water?

Abrasion. Rock particles collide and wear down surfaces mechanically.
What is oxidation as a weathering process?

Oxygen reacts with minerals (often iron), forming oxides (rust). Common in iron-rich rocks; creates reddish-brown weathering products.
Which process builds a delta at a river mouth?

Deposition of sediment as river water slows. River velocity drops where it meets ocean or lake.
Which agent of erosion most commonly forms sand dunes and creates wind abrasion in deserts?

Wind. Carries fine particles and sandblasts exposed surfaces.
What is the difference between weathering and erosion?

Weathering breaks rock; erosion moves sediment. Weathering is in-place breakdown; erosion involves transport.
Which wind-formed landform is a mound or ridge of sand built by deposition?

Sand dune. Wind deposits sand when velocity decreases.
What is frost wedging?

Cracking of rock as water freezes and expands in fractures. Water expands 9% when freezing, creating pressure that splits rock.
Which process most directly forms a delta at a river mouth: erosion or deposition?

Deposition. Rivers slow at ocean, dropping sediment in triangular patterns.
Which chemical weathering process occurs when acidic water dissolves limestone?

Carbonation (acid dissolution). Carbonic acid from CO₂ and water reacts with carbonate minerals.
Identify the weathering process where roots pry rocks apart.

Biological mechanical weathering (root wedging). Plant roots grow into cracks and physically split rock.
Which type of mass movement is a rapid downhill flow of water-saturated sediment?

Mudflow. Heavy rain saturates soil, creating a flowing mixture.
Identify the landform formed when a river deposits sediment at its mouth into a lake or ocean.

Delta. River velocity drops at mouth, causing sediment to settle.
Identify the plate-tectonic process that builds mountains when two continental plates collide.

Continental-continental convergence. Plates crumple and fold upward, forming ranges like the Himalayas.
Which process directly moves sediment downhill due to gravity alone?

Mass wasting. Gravity pulls loose material down slopes without other agents.
Which type of weathering occurs when plant roots grow into cracks and split rock?

Mechanical weathering (root wedging). Growing roots exert pressure, physically splitting rock apart.
Which internal process builds mountains when tectonic plates collide and compress crust?

Plate tectonics (compression and uplift). Convergent boundaries fold and fault crust upward.
Which agent of erosion most commonly carves U-shaped valleys and leaves moraines?

Glaciers (moving ice). Glaciers scour valleys wider and deeper, depositing debris as moraines.
Which agent of erosion most directly forms U-shaped valleys and deposits unsorted till?

Glaciers (moving ice). Ice plucks and grinds rock as it moves downslope.
Which internal geoscience process builds land by releasing magma and lava at the surface?

Volcanism (volcanic activity). Molten rock erupts, cooling to form new landforms.
Which agent of erosion most directly carves V-shaped valleys and canyons over long time periods?

Running water (streams and rivers). Flowing water cuts downward through rock over time.
What is deposition in the context of surface-shaping processes?

The dropping and settling of transported sediment. Occurs when erosion agents lose energy and release their load.
What is weathering (in Earth science) as a surface-shaping process?

Breakdown of rock at Earth's surface by physical or chemical means. Weathering breaks down rock in place, unlike erosion which moves material.
What is biological weathering?

Rock breaks or changes due to living organisms (roots, acids). Plants and animals cause both physical and chemical breakdown.
Which agent of erosion moves sediment downslope due to gravity, such as landslides?

Gravity (mass wasting). Pulls loose material directly downhill without other transport agents.
Which process wears rock by scraping and grinding during transport?

Abrasion. Sediment particles act like sandpaper on rock surfaces.
Which process is the main internal source of energy that drives mountain building and volcanism?

Earth's internal heat (plate tectonics). Convection currents drive crustal movement and volcanic activity.
Identify the surface-shaping process where lava cools and hardens into new rock.

Volcanic eruption and lava solidification. Molten rock reaches surface and forms new igneous rock.
Identify the mass wasting event: rapid downhill movement of a large block of rock along a surface.

Landslide (rockslide). Rock masses slide along fracture planes when support is removed.
Identify the plate-boundary process that builds mountain ranges by collision.

Convergent plate collision (continental-continental convergence). Plates compress and fold crust upward, forming ranges like Himalayas.
Identify the agent of erosion that typically forms sand dunes.

Wind. Wind deposits sand when velocity decreases behind obstacles.
What is a delta?

Sediment deposit at a river mouth where it enters a lake or ocean. Rivers slow and drop sediment when entering standing water.
Which agent of erosion commonly creates U-shaped valleys and deposits moraines?

Glaciers (moving ice). Ice carves wide valleys and leaves debris piles when melting.
Which type of boundary mainly causes earthquakes that offset land without creating or destroying crust?

Transform boundary. Plates slide past each other without creating/destroying.
Which process changes a rock's minerals into different substances?

Chemical weathering. Reactions alter mineral composition, creating new compounds.
What is abrasion in the context of surface-shaping processes?

Sediment scrapes surfaces and wears them down. Moving particles act like sandpaper on rock surfaces.
Which agent of erosion most directly forms V-shaped valleys and canyons?

Running water (streams and rivers). Water cuts downward faster than sideways, creating steep sides.
What chemical weathering process forms new clay minerals when water reacts with feldspar?

Hydrolysis. Water molecules break down feldspar's structure, creating clay minerals.
Which agent of erosion is most effective in dry regions at moving sand and forming dunes?

Wind. Carries fine particles where water is scarce.
Which process causes land to rise or sink due to movement of magma or changes in crustal stress?

Tectonic uplift or subsidence. Vertical crustal movement from tectonic forces or isostatic adjustment.
Identify the plate boundary most associated with rift valleys and seafloor spreading.

Divergent plate boundary. Plates pull apart, creating valleys and new ocean floor.
What is the difference between weathering and erosion?

Weathering breaks rock; erosion moves sediment. Weathering is in-place breakdown; erosion is transport.
Identify the process: ocean waves undercut a cliff and the cliff collapses.

Coastal erosion by wave action. Waves remove support from cliff base, causing collapse.
Identify the process: Wind-blown sand scratches rock surfaces, making them smoother over time.

Mechanical weathering (abrasion). Sand particles physically scrape and polish rock surfaces.
Which mass movement is a rapid downhill flow of water-saturated soil and debris?

Mudflow. Heavy rain saturates soil, reducing friction and causing flow.
Which agent of erosion reshapes coastlines through wave action and longshore currents?

Ocean waves and currents. Wave energy erodes headlands and builds beaches.
Which agent of erosion most commonly forms U-shaped valleys?

Glaciers (moving ice). Ice plucks and scours bedrock, creating broad, flat-bottomed valleys.
Identify the plate boundary most associated with deep-ocean trenches and volcanic arcs.

Convergent boundary with subduction. Oceanic plate sinks beneath another, melting to fuel volcanoes.
Which process directly breaks rock into smaller pieces: weathering, erosion, or deposition?

Weathering. Only weathering breaks rocks in place; erosion moves pieces.
Which agent of erosion most commonly carves V-shaped valleys in mountains?

Running water (streams and rivers). Rivers cut downward faster than they widen, creating V-shaped profiles.
Identify the landform built when a river deposits sediment at its mouth.

Delta. Forms where river velocity drops entering standing water.
Which process most directly reduces steep slopes by moving material downhill?

Mass wasting. Gravity pulls unstable material from oversteepened slopes.
What type of weathering changes a rock's minerals into new substances?

Chemical weathering. Reactions alter mineral composition, creating different compounds.
What is the geoscience process that breaks rock into smaller pieces without moving it?

Weathering. Physical or chemical breakdown occurs in place without transport.
Which wind-formed landform is created mainly by deposition: dune or canyon?

Dune. Wind deposits sand when velocity decreases, building hills.
Which tectonic setting most commonly produces major earthquakes along strike-slip faults?

Transform plate boundary. Plates slide past each other, causing frequent earthquakes.
Which agent of erosion most commonly forms sand dunes and wind-blown sand deposits?

Wind. Wind sorts particles by size, depositing sand in characteristic dune shapes.
Which geoscience process breaks rock into smaller pieces without moving it?

Weathering. Breaks down rock in place through physical or chemical processes.
Which surface-shaping process is driven by plate motion and builds mountains?

Tectonic uplift (mountain building). Colliding plates compress and fold crust into mountain ranges.
Which type of weathering occurs when water freezes and expands in cracks?

Ice wedging (freeze–thaw weathering). Water expands 9% when freezing, widening rock fractures.
What type of weathering occurs when roots grow into cracks and force rock apart?

Root wedging (biological mechanical weathering). Growing roots exert pressure as they thicken, splitting rock mechanically.
Identify the mass movement where soil slowly creeps downhill over time.

Creep. Gravity causes imperceptible downslope movement over years.
What process moves soil and rock downslope due to gravity, such as landslides and mudflows?

Mass movement (mass wasting). Gravity pulls loose material down steep slopes.
Identify the plate-tectonic process that builds mountain ranges when plates collide.

Convergent plate collision (compression and uplift). Plates push together, crumpling and thickening crust upward.
Which plate boundary type most commonly forms deep-ocean trenches?

Convergent boundary with subduction. One plate sinks beneath another, creating deep valleys.
Identify the mass movement that is a slow, downhill movement of soil that bends trees and poles.

Creep. Imperceptible movement, often just cm/year.

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