Untitled Document

Quiz 2

What to study:

Thermal Regime, Glacial Flow, Meltwater and Glacial Erosion (small and large scale features) Outlines
Movie Guide: Warnings From the Ice (Nova)
Bennett and Glasser: Chapters 3-7
Crossword: interactive/printable

Glacial Flow, Thermal Regime, and Erosion

Temporal and spacial thermal variations typically occur beneath an ice sheet. What does this mean? Discuss an example.
List and briefly explain the various mechanisms of glacial flow.
How does basal meltwater influence glacial flow.
Discuss the meaning and significance of the following formulas:
- T=phg sin Ø and E = ATⁿ
Explain why the velocity of a glacier is greatest at its surface while the greatest rate of creep is at the base.
How do variations in temperature, crystal orientation, and chemical impurities influence internal deformation.
Explain why eskers are typically oriented parallel to the direction of ice flow.
Explain why ice at the base of a glacier can melt at a lower temperature that ice at its surface.
List and discuss the fundamental requirements of abrasion.
List and discuss the general factors that control the amount of erosion by a glacier.
Why does greatest amount of erosion typically occur beneath the equilibrium line in alpine glaciers.
Why is abrasion beneath a warm-based glacier more effective than beneath a cold base glacier?
Discuss how variations in the basal thermal regime of a glacier influence processes of glacial erosion. (sec. 5.5 text, fig 5.9)
Outline and discuss the two erosion models by Boulton and Hallet. How do they differ? (sec.5.1.4 text)
List and discuss the range of fractures that are excavated by glaciers.
- How can dilation joints from beneath a valley glacier.
List and discuss the different mechanism in which a glacier entrains debris. (sec.5.2.2 text)
- Describe Robin's heat pump effect. How is this process responsible for the entrainment of debris? (p. 91 text)
- How and why do large amounts of debris become entrained when a glacier changes from warm to cold based conditions?
How does extending and compressive flow affect abrasion and entrainment beneath a glacier?
List and describe the various features of erosion that are good flow indicators.
How and why does the landscape created by continental glaciation differ from that created by alpine glaciation?
How does the morphology of a glacial valley differ from that of a stream valley?
Explain why glacial valleys are so much larger than stream valleys.
According to Harbor et al. (1988) how do glacial troughs develop their parabolic shape. (Box 6.4 text)
Why does sediment transported at the base of the glacier (zone of traction) typically have a bimodal distribution of grain sizes.(p. 158 text)
How are glacial landforms used to reconstruct former glaciers. (p. 43 text, and Hughes, et al., 1985)

Terms: ice dome, ice stream, ice divide, streaming flow, sheet flow, ice cap, ice sheet, outlet glacier, ice shelf, ice rise, shear stress, basal sliding, subsole deformation, internal deformation, plastic deformation (creep), brittle deformation (crevassing), pressure melting point, warm based glacier, cold based glacier, basal sliding, converging flow, diverging flow, extending flow, compressive flow, sheet flow, supraglacial, englacial, subglacial, marginal (chevron) crevasses, jokulhlaup, moulin, Nye or N-channels, Rothlisberger or R-channels, glacial lake, striation, whaleback, roche moutonee,crescent gouges, chatter marks, crescent fractures, glacial trough, cirque, arete, col, horn, pater nostra lakes, tarn, craig and tail, friction cracks, plucking and quarrying, regelation, adhesion, plastically mould ed forms, stoss and lee topography, tunnel valleys, knock and lochan topography, areal scour

[Glacial and Quaternary Geology] [extended GeoIndex][QkRef][Geological Sciences] [Degree Programs] [Salem State College]
Lindley Hanson (email) Last Modified 4/2/03