Earth Science Quiz: Glacial Processes

What this quiz covers

This quiz focuses on Glacial Processes, giving you a quick way to practice the rules, question types, and explanations that matter most for Earth Science.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. Sublimation on the upstream side and deposition on the downstream side.
2. Fluvial erosion on the upstream side and eolian erosion on the downstream side.
3. Abrasion on the upstream side and plucking on the downstream side. (correct answer)
4. Plucking on the upstream side and abrasion on the downstream side.

Explanation: A roche moutonnée is a classic indicator of glacial flow direction. As the glacier flows over the bedrock knob, the upstream (stoss) side is smoothed and polished by abrasion from the rock-laden ice. On the downstream (lee) side, pressure is reduced, allowing meltwater to freeze in cracks and pull away blocks of rock in a process called plucking or quarrying, creating a steep, jagged face.

Question 2

1. A landscape shaped primarily by continental glaciation and subsequent isostatic rebound.
2. An area of active tectonic uplift and rapid fluvial (river) erosion.
3. A maturely dissected landscape shaped by extensive alpine glaciation. (correct answer)
4. A coastal region recently submerged due to a rise in sea level.

Explanation: This question describes a classic suite of alpine glacial erosion features. The knife-edge ridges are arêtes, the pyramidal peaks are horns, the wide valleys are U-shaped valleys, and the perched tributary valleys are hanging valleys. Together, these indicate extensive erosion by valley glaciers in a mountainous area (alpine glaciation).

Question 3

1. The polar desert, because the extreme cold ensures that any precipitation that falls will be preserved as ice indefinitely.
2. The mid-latitude mountain range, because high rates of snowfall are more critical for glacier formation than extreme cold. (correct answer)
3. Both locations are equally likely, as the lower precipitation in the polar region is balanced by its much colder temperatures.
4. Neither location, as persistent glaciers require both extremely low temperatures and extremely high rates of precipitation.

Explanation: Glacier formation depends on a positive mass balance, where annual snow accumulation exceeds annual ablation (melting and sublimation). While cold temperatures reduce ablation, there must be sufficient accumulation (snowfall) to build up ice. The mid-latitude mountain range has vastly more accumulation, making it much more likely to form a glacier, even with milder winters, than the precipitation-starved polar desert.

Question 4

1. Deposit A is glacial till, and Deposit B is glacial outwash (stratified drift). (correct answer)
2. Deposit A is glacial outwash, and Deposit B is glacial till.
3. Both deposits are types of till, with Deposit B having been transported a longer distance.
4. Deposit A is wind-deposited loess, and Deposit B is a river's alluvial deposit.

Explanation: Deposit A's characteristics (unsorted, unstratified, angular clasts) are definitive of till, which is deposited directly by glacial ice. Deposit B's characteristics (sorted, rounded, stratified) indicate deposition by flowing water, which is characteristic of glacial outwash (stratified drift) deposited by meltwater streams.

Question 5

1. The glacier's terminus will advance due to increased accumulation.
2. The glacier will experience a net loss of mass and its terminus will retreat. (correct answer)
3. The velocity of the glacier's flow will increase significantly, causing a surge.
4. The glacier will remain in a state of equilibrium, with no change in its terminus position.

Explanation: The equilibrium line separates the zone of accumulation from the zone of ablation. If the ELA moves to a higher elevation, the zone of accumulation shrinks and the zone of ablation expands. This results in a negative mass balance (more melting than snowfall), causing the glacier to lose mass and its terminus to retreat up-valley.

Question 6

1. A glacier flowed from north to south, creating striations and depositing the boulders as erratics. (correct answer)
2. A glacier flowed from south to north, pushing the anorthosite boulders ahead of it.
3. The grooves are tectonic faults, and the boulders were brought to the surface by volcanic activity.
4. A massive flood transported the boulders from the south and carved the grooves into the bedrock.

Explanation: This requires synthesizing two pieces of evidence. The parallel grooves are glacial striations, indicating the axis of ice flow (north-south). The anorthosite boulders are glacial erratics, which are rocks transported by a glacier from a distant source. Since the source outcrop is to the north, the glacier must have flowed from north to south, carrying the erratics and carving the striations.

Question 7

1. drumlin.
2. kettle lake. (correct answer)
3. pingo.
4. roche moutonnée.

Explanation: The scenario describes the classic formation of a kettle. When a buried block of glacial ice melts, the overlying sediment collapses, leaving a depression or hole that often fills with water to become a kettle lake. Drumlins and roches moutonnées are formed by advancing ice, not melting stagnant ice. A pingo is an ice-cored hill that forms in permafrost regions, a different process.

Question 8

1. It is a terminal moraine, marking the farthest advance of the glacier's terminus, composed of till dropped at the ice front.
2. It is a drumlin, formed when the advancing glacier reshaped underlying till into an elongated, asymmetrical hill.
3. It is an esker, formed by the deposition of sediment from a meltwater stream flowing in a tunnel beneath a stagnant glacier. (correct answer)
4. It is a kame, created when sediment accumulated in a depression on the glacier's surface and was later lowered to the ground.

Explanation: The key characteristics are 'long, narrow, sinuous ridge' and 'well-sorted...sand and gravel'. This combination points to an esker, which is the deposit of a subglacial or englacial stream. Moraines and drumlins are composed of unsorted till. A kame is a mound or hillock of sorted sediment, not a long, sinuous ridge.

Question 9

1. From southeast to northwest, with the ice overriding the gentle slope first.
2. From northwest to southeast, with ice moving up the steep slope and down the gentle slope. (correct answer)
3. From southwest to northeast, perpendicular to the main axis of the hills.
4. The direction cannot be determined without knowing the composition of the hills.

Explanation: These features are drumlins. Ice flows over a drumlin from the steep (stoss) side to the gentle (lee) side. Since the steep side faces northwest and the gentle slope tapers to the southeast, the continental ice sheet must have been flowing from the northwest towards the southeast.

Question 10

1. a very rapid and continuous retreat with extensive meltwater flooding.
2. prolonged, intense erosion that removed most depositional features.
3. a series of regular advances and retreats, each one smaller than the last.
4. a period of stagnation and downwasting at the terminus before final retreat. (correct answer)

Explanation: When you encounter questions about glacial landform sequences, think about how different retreat patterns create distinct depositional signatures in the landscape. The described sequence—terminal moraine, then hummocky terrain with ponds, then smooth till sheet—tells a specific story about glacier behavior. The terminal moraine marks where the glacier's terminus stabilized for an extended period. The hummocky terrain immediately behind it, characterized by irregular mounds and kettle ponds, is classic stagnant ice topography. This forms when a glacier stops advancing but doesn't immediately retreat; instead, the ice becomes motionless and gradually melts in place (downwasting). As buried ice blocks melt, they create the irregular, "knob and kettle" landscape with depressions that fill with water. The smooth till sheet farther up-valley represents normal subglacial deposition when the glacier was actively flowing. Answer D correctly describes this stagnation and downwasting process. Answer A is wrong because rapid retreat with extensive meltwater would create outwash plains and channels, not hummocky terrain with small ponds. Answer B is incorrect because intense erosion would remove depositional features entirely, yet we see abundant till deposits. Answer C describes oscillating ice margins, which would create multiple moraines at different positions, not the single terminal moraine described. Remember that hummocky terrain with kettle ponds is the diagnostic signature of stagnant ice. When you see this landscape feature on exams, think "downwasting" rather than active retreat or advance.

Question 11

1. the deposition of thick, low-density sediments like till and outwash across the landscape.
2. the thermal expansion of the crust as the regional climate has warmed since the last ice age.
3. increased tectonic activity along plate margins triggered by changes in global sea level.
4. the lithosphere isostatically adjusting to the removal of the immense weight of continental ice sheets. (correct answer)

Explanation: When you encounter questions about land surface changes in formerly glaciated regions, think about isostatic equilibrium—the balance between Earth's crust and the underlying mantle. Post-glacial rebound occurs because massive continental ice sheets, sometimes over a mile thick, pressed down on the lithosphere for thousands of years during ice ages. This immense weight caused the crust to slowly sink into the more fluid asthenosphere below, like pressing down on a floating piece of wood. When the ice melted around 10,000-12,000 years ago, the lithosphere began slowly rising back toward its original position—a process called isostatic adjustment. This makes answer D correct. Answer A is wrong because sediment deposition would actually add weight to the surface, potentially causing subsidence rather than uplift. Answer B incorrectly attributes the movement to thermal expansion from warming climate, but the scale and timing don't match—post-glacial rebound continues today at measurable rates (several millimeters per year) and is purely mechanical, not thermal. Answer C suggests tectonic activity triggered by sea level changes, but post-glacial rebound occurs far from plate boundaries and is driven by local ice removal, not global sea level fluctuations. Remember that isostatic processes involve vertical crustal movements in response to loading and unloading. Whenever you see questions about land rising in formerly glaciated areas like Scandinavia, Hudson Bay, or the Great Lakes region, think "ice weight removal" and isostatic rebound—this is one of the clearest examples of how Earth's systems respond to changing surface loads.

Question 12

1. The glacier's terminus will advance due to increased accumulation.
2. The glacier will experience a net loss of mass and its terminus will retreat. (correct answer)
3. The velocity of the glacier's flow will increase significantly, causing a surge.
4. The glacier will remain in a state of equilibrium, with no change in its terminus position.

Explanation: The equilibrium line separates the zone of accumulation from the zone of ablation. If the ELA moves to a higher elevation, the zone of accumulation shrinks and the zone of ablation expands. This results in a negative mass balance (more melting than snowfall), causing the glacier to lose mass and its terminus to retreat up-valley.

Question 13

1. From southeast to northwest, with the ice overriding the gentle slope first.
2. From northwest to southeast, with ice moving up the steep slope and down the gentle slope. (correct answer)
3. From southwest to northeast, perpendicular to the main axis of the hills.
4. The direction cannot be determined without knowing the composition of the hills.

Explanation: These features are drumlins. Ice flows over a drumlin from the steep (stoss) side to the gentle (lee) side. Since the steep side faces northwest and the gentle slope tapers to the southeast, the continental ice sheet must have been flowing from the northwest towards the southeast.

Question 14

1. a very rapid and continuous retreat with extensive meltwater flooding.
2. prolonged, intense erosion that removed most depositional features.
3. a series of regular advances and retreats, each one smaller than the last.
4. a period of stagnation and downwasting at the terminus before final retreat. (correct answer)

Explanation: When you encounter questions about glacial landform sequences, think about how different retreat patterns create distinct depositional signatures in the landscape. The described sequence—terminal moraine, then hummocky terrain with ponds, then smooth till sheet—tells a specific story about glacier behavior. The terminal moraine marks where the glacier's terminus stabilized for an extended period. The hummocky terrain immediately behind it, characterized by irregular mounds and kettle ponds, is classic stagnant ice topography. This forms when a glacier stops advancing but doesn't immediately retreat; instead, the ice becomes motionless and gradually melts in place (downwasting). As buried ice blocks melt, they create the irregular, "knob and kettle" landscape with depressions that fill with water. The smooth till sheet farther up-valley represents normal subglacial deposition when the glacier was actively flowing. Answer D correctly describes this stagnation and downwasting process. Answer A is wrong because rapid retreat with extensive meltwater would create outwash plains and channels, not hummocky terrain with small ponds. Answer B is incorrect because intense erosion would remove depositional features entirely, yet we see abundant till deposits. Answer C describes oscillating ice margins, which would create multiple moraines at different positions, not the single terminal moraine described. Remember that hummocky terrain with kettle ponds is the diagnostic signature of stagnant ice. When you see this landscape feature on exams, think "downwasting" rather than active retreat or advance.

Question 15

1. A landscape shaped primarily by continental glaciation and subsequent isostatic rebound.
2. An area of active tectonic uplift and rapid fluvial (river) erosion.
3. A maturely dissected landscape shaped by extensive alpine glaciation. (correct answer)
4. A coastal region recently submerged due to a rise in sea level.

Explanation: This question describes a classic suite of alpine glacial erosion features. The knife-edge ridges are arêtes, the pyramidal peaks are horns, the wide valleys are U-shaped valleys, and the perched tributary valleys are hanging valleys. Together, these indicate extensive erosion by valley glaciers in a mountainous area (alpine glaciation).

Question 16

1. The ridge is an esker, and the plain is a delta that formed in a proglacial lake.
2. The ridge is a lateral moraine, and the plain is a terrace formed by glacial meltwater.
3. The ridge is a beach ridge from an ancient lake, and the plain is the former lake bed.
4. The ridge is a terminal moraine, and the plain is a corresponding outwash plain. (correct answer)

Explanation: When you encounter questions about glacial landforms, focus on identifying diagnostic features and their spatial relationships. The key clues here are the arc-shaped ridge of poorly sorted sediments and the layered deposits extending from its convex side. The ridge described is a terminal moraine - a accumulation of glacial till (poorly sorted boulders, sand, and clay) deposited at the farthest advance of a glacier. The arc shape is characteristic because glaciers typically have curved fronts, and "poorly sorted" sediments are a hallmark of direct glacial deposition. The broad plain of layered sand and gravel extending from the convex (downslope) side is an outwash plain, formed by meltwater streams carrying and sorting sediments away from the glacier terminus. Option A is incorrect because eskers are long, winding ridges formed within glacial tunnels, not arc-shaped ridges at glacier fronts. Option B misidentifies the ridge as a lateral moraine, which forms along glacier sides, not at the terminus, and the described plain is too extensive to be a simple terrace. Option C describes lacustrine (lake) features, but beach ridges form parallel to shorelines and lack the poorly sorted glacial till composition described. The spatial arrangement - an arc-shaped ridge with sediments extending away from its convex side - is the classic signature of a terminal moraine-outwash plain system. For glacial landform questions, always consider both composition (sorted vs. unsorted sediments) and spatial relationships between features. Terminal moraines and outwash plains are commonly paired features that appear together in formerly glaciated landscapes.

Question 17

1. Sublimation on the upstream side and deposition on the downstream side.
2. Fluvial erosion on the upstream side and eolian erosion on the downstream side.
3. Abrasion on the upstream side and plucking on the downstream side. (correct answer)
4. Plucking on the upstream side and abrasion on the downstream side.

Explanation: A roche moutonnée is a classic indicator of glacial flow direction. As the glacier flows over the bedrock knob, the upstream (stoss) side is smoothed and polished by abrasion from the rock-laden ice. On the downstream (lee) side, pressure is reduced, allowing meltwater to freeze in cracks and pull away blocks of rock in a process called plucking or quarrying, creating a steep, jagged face.

Question 18

1. Sea-level fall, river incision to create a V-shaped valley, sea-level rise to flood the valley.
2. Glacial advance carves a U-shaped valley below sea level, followed by tectonic uplift of the coastline.
3. A river carves a V-shaped valley, a glacier widens and deepens it into a U-shaped trough, and then a rise in sea level floods the trough. (correct answer)
4. Tectonic rifting creates a deep valley, a glacier deposits moraines within it, and then the glacier melts.

Explanation: A fjord is a drowned glacial valley. The formation requires a three-step process in the correct order: 1) A pre-existing river valley forms. 2) A valley glacier moves through, eroding the valley into a deep, steep-sided U-shaped trough, often with its floor below current sea level. 3) After the glacier retreats, post-glacial sea-level rise floods the trough, creating a long, narrow inlet of the sea.

Question 19

1. Deposit A is glacial till, and Deposit B is glacial outwash (stratified drift). (correct answer)
2. Deposit A is glacial outwash, and Deposit B is glacial till.
3. Both deposits are types of till, with Deposit B having been transported a longer distance.
4. Deposit A is wind-deposited loess, and Deposit B is a river's alluvial deposit.

Explanation: Deposit A's characteristics (unsorted, unstratified, angular clasts) are definitive of till, which is deposited directly by glacial ice. Deposit B's characteristics (sorted, rounded, stratified) indicate deposition by flowing water, which is characteristic of glacial outwash (stratified drift) deposited by meltwater streams.

Question 20

1. A glacier flowed from north to south, creating striations and depositing the boulders as erratics. (correct answer)
2. A glacier flowed from south to north, pushing the anorthosite boulders ahead of it.
3. The grooves are tectonic faults, and the boulders were brought to the surface by volcanic activity.
4. A massive flood transported the boulders from the south and carved the grooves into the bedrock.

Explanation: This requires synthesizing two pieces of evidence. The parallel grooves are glacial striations, indicating the axis of ice flow (north-south). The anorthosite boulders are glacial erratics, which are rocks transported by a glacier from a distant source. Since the source outcrop is to the north, the glacier must have flowed from north to south, carrying the erratics and carving the striations.