1. Glaciers and Mass Movements

2. Glaciers vs Icebergs Glaciers: A large, MOVING mass of ice
Iceberg: A large floating mass of ice broken off from a glacier

3. Glacial Features Hanging Valley / U-shaped Valley / Glacial Trough:
Steep sided, flat bottomed valley formed after a moving and melting event.
Arêtes:
A thin, sharp ridge of rock when parallel U-shaped valleys exist beside one another. *

6. Glacial Features
Horns: Pyramidal peaks that are carved out by advancing and receding glacial deposits
Cirques: Hollow, semi-circular, bowl-shaped area of rock carved out by a glacier

7. Matterhorn (Between Italy and Switzerland)

9. Glaciers are described as the “Most Erosive Force in Nature”

10. Weathering versus Erosion
Weathering refers to the physical and/or chemical break down of materials through natural processes
Erosion refers to the movement of that material.

11. Deposition Features
Till / Sediment refers to unsorted rock, gravel, sand, and clay that are carried by glaciers
Moraines: Till and sediment deposited by a glacier, typically at its terminal regions. *

13. Deposition Features
Outwash Plains: An area generally below a glacier that is exposed to glacial melt water.
Drumlins: Moraines that add to each other over time
Eskers: A ridge of till left from melt water running underneath a glacier

16. Glacial Budget Accumulation: The build up of snow and ice
Ablation: The removal of snow and ice through abrasion, melting, evaporation and other erosive properties
Glacier Budget = Accumulation – Ablation
If the rate of accumulation exceeds the rate of ablation, the glacier grows

17. Mass Movement
The down slope movement of soil and weathered rock resulting from the force of gravity
Occurrence due to:
Weight
Resistance to flow (anchorage, cohesiveness, etc)
A trigger (seismic activity)
Water (saturation)

18. Types of Mass Movements
Creep
The slow, steady, downhill flow of loose, weathered materials
Solifluction: A type of creep that involves melting permafrost
Mudflow:
Fast moving flow of mud and water

19. Types of Mass Movements
Landslide:
Rapid movement of Earth materials due to detachment of rock layers from an underlying layer of rock
Slump:
When a landslide happens along a curved surface.

20. Types of Mass Movements
Avalanche:
Landslides that occur in mountainous regions with thick accumulations of snow

21. Mass Movements by Wind
Deflation: The lowering of a land surface by the removal of surface particles by wind.
Abrasion leading to ventifacts

22. Mass Movements by Wind
Abrasion: the specific weathering process associated with sand rubbing against surfaces of other rock.
Think “natural sand blasting’
Ventifacts: Rock shaped by abrasion (windblown sediments)

25. Deposition by Wind Dunes Loess Piles of windblown sand particles
Continual wind may cause dune to migration
Barchan, Transverse, Parabolic and Longitudinal (table 8.1)
Loess

26. Deposition by Wind Dunes Loess
Barchan, Transverse, Parabolic and Longitudinal (table 8.1) all have predictable characteristics
Loess
Windblown particle deposits that travel great distances through time
Often make for extremely rich soils since they are heterogeneous

27. Try these questions
P. 200 Q: 5, 6
P. 206 Q: 2, 3
p. 212 Q: 3, 4