Unit 5: Fluvial and glacial processes - Practice Quiz

1 What is the wearing away of river banks and beds called?

2 What is the process by which a river drops the sediment it carries?

3 Which river feature is a looping bend in the channel?

4 What is a waterfall?

5 What is the wide, flat area beside a river that may flood called?

6 Which process involves a river carrying sediment downstream?

7 What is a delta?

8 Which river feature is commonly found where a river enters the sea?

9 What is a river's mouth?

10 Which landform is a steep-sided valley commonly associated with river erosion?

11 What is a glacier?

12 What is the process by which a glacier carries rocks and sediment?

13 What is glacial till?

14 Which valley shape is commonly produced by glacial erosion?

15 What is a moraine?

16 What is a cirque?

17 Which process occurs when a glacier freezes onto rocks and pulls them away?

18 Which process occurs when rocks carried by ice scrape the land surface?

19 What is an arête?

20 Which landform is a streamlined hill of glacial sediment?

21 A river enters a broad, flat valley and loses velocity because its gradient decreases. Which change is most likely to occur?

22 Which condition would most directly increase a river's competence during a flood?

23 A river cuts downward through resistant bedrock, leaving steep valley sides and a narrow floor. Which landform is most likely present?

24 A meander becomes increasingly curved, and erosion occurs on the outer bank while deposition occurs on the inner bank. What is the likely result?

25 Why does a river commonly deposit a fan-shaped accumulation where it leaves a steep mountain valley and enters a plain?

26 Which sequence best describes the formation of a waterfall where a resistant rock layer overlies a weaker layer?

27 A floodplain becomes wider downstream even though the river's discharge increases. Which explanation is most appropriate?

28 A river carries a large quantity of sediment but has variable discharge and several shifting channels separated by bars. Which landform is indicated?

29 During a flood, a river's discharge increases from to while channel area remains constant. What happens to average velocity?

30 A river deposits coarse sediment near its mouth and finer sediment farther offshore, producing a triangular feature. Which landform is this?

31 A glacier moves over bedrock containing joints and pulls blocks from the rock surface. Which process is primarily responsible?

32 A glacier contains rock fragments at its base that scrape and polish the underlying bedrock. Which process is occurring?

33 Which valley profile most strongly indicates that a former river valley was enlarged by glacial erosion?

34 A smaller tributary valley ends high above the floor of a main glacial trough. Which landform is present?

35 A streamlined hill has a blunt end facing the direction from which ice advanced and a tapered end pointing down-ice. Which landform is described?

36 A knife-edged ridge separates two cirques on opposite sides of a mountain. Which process best explains its formation?

37 A ridge of unsorted sediment marks the furthest position reached by a glacier during its advance. What is this ridge called?

38 Two valley glaciers merge and their inner lateral moraines join to form a debris band down the center of the larger glacier. What is this feature?

39 A sinuous ridge of sorted sand and gravel remains after an ice sheet melts. Which depositional feature is most likely?

40 A bowl-shaped hollow with a steep headwall contains a small tarn at the upper end of a glacial valley. Which landform is this?

41 A meandering river has a constant discharge but experiences a sudden increase in bankfull width downstream. Which adjustment is most likely immediately downstream of the widening?

42 A river transports abundant sediment during a flood, but its channel gradient and discharge decline across a broad valley. Which downstream pattern is most consistent with the resulting sediment budget?

43 A braided river is dammed, trapping most of its coarse sediment while maintaining relatively regular downstream discharge. Which channel response is most likely below the dam?

44 Two rivers have identical discharge and channel slope. River A has a rough, shallow, wide channel; River B has a smoother, deeper, narrower channel. Which river generally has greater boundary shear stress at the bed?

45 A river develops a cutoff across a narrow meander neck during a flood. What sequence best describes the subsequent evolution of the abandoned loop?

46 A river terrace occurs at the same elevation on both sides of a valley, while a younger channel is deeply incised below it. Which interpretation is strongest?

47 A steep tributary enters a low-gradient main river and forms a fan-like sediment body at the junction. Which change would most strongly promote its development?

48 A knickpoint forms after a sharp fall in base level. Which observation would best distinguish upstream propagation of the knickpoint from simple downstream channel aggradation?

49 A river's suspended load increases greatly after deforestation, but its bed-load supply changes little. Which landform response is most plausible in a low-gradient reach?

50 A river enters a standing lake and forms distributary channels with a lobate sediment body. Which condition would favor a river-dominated delta rather than a wave-dominated delta?

51 A glacier has a negative mass balance for several decades but its terminus remains stationary. Which explanation is most defensible?

52 A U-shaped valley contains truncated spurs, hanging tributary valleys, and a broad flat floor. Which process combination best explains the assemblage?

53 A roche moutonnée has a smooth stoss side and a steep, plucked lee side. What does this asymmetry indicate about former ice movement?

54 A drumlin field contains streamlined hills whose long axes are parallel to striation directions. Which interpretation is most appropriate?

55 A ridge of unsorted till lies transverse to a valley, and meltwater channels diverge away from its outer side. Which landform is most likely represented?

56 A sinuous ridge of stratified sand and gravel crosses beneath a former ice-sheet landscape. Why is it unlikely to be a moraine?

57 A proglacial lake drains catastrophically through an ice-dammed outlet. Which geomorphic evidence would most strongly support a jökulhlaup interpretation?

58 A glacier terminates in seawater, and large icebergs calve from a floating tongue. Which process most directly increases the likelihood of rapid retreat?

59 A valley glacier leaves a sediment ridge along both valley sides but no continuous ridge at its terminus. What is the most likely explanation?

60 A sequence of lake sediments contains alternating light and dark couplets, with the coarser layers consistently deposited during summer. What process most likely produced the sequence?