Glaciers and Glacial Mechanics

1. Glaciers and Glacial Mechanics

2. Glacier Origins and Types

3. Glacier Origins and Types • Glacier (def): a body of moving ice that has been formed on • land by compaction and recrystallization of snow.

4. Glacier Origins and Types • Glacier (def): a body of moving ice that has been formed on • land by compaction and recrystallization of snow. • B. Critical Requirements

5. B. Critical Requirements • Must be formed from the accumulation and ‘metamorphism’ • of snow.

6. B. Critical Requirements • Must be formed from the accumulation and ‘metamorphism’ • of snow. • 2. Ice must be moving under its own weight.

7. B. Critical Requirements • Must be formed from the accumulation and ‘metamorphism’ • of snow. • Ice must be moving under its own weight. • Must originate on land

8. B. Critical Requirements • Must be formed from the accumulation and ‘metamorphism’ • of snow. • Ice must be moving under its own weight. • Must originate on land • Persist from year-to-year

9. Glacier Origins and Types • C. The recrystallization of snow

13. II. The Movement of Glaciers

14. II. The Movement of Glaciers • Basal Sliding

16. II. The Movement of Glaciers • Basal Sliding • Plastic Flow

17. II. The Movement of Glaciers • Basal Sliding • Plastic Flow • Internal Shearing

19. II. The Movement of Glaciers D. Crevassing (Zone of Fracture)

20. Crevasses

21. Crevasses

22. The Glacial Budget • Zone of Accumulation • Zone of Ablation • Equilibrium Line

25. “fastest velocity at equilibrium line”

26. IV. Classification of Glaciers

27. IV. Classification of Glaciers • Descriptive-based • Process-based

28. IV. Classification of Glaciers • Descriptive-based • * Cirque Glaciers • * Valley Glaciers • * Ice Sheets

29. IV. Classification of Glaciers • Descriptive-based • Process-based • 1. Dynamic classification scheme • * Active • * Passive • * Dead

30. IV. Classification of Glaciers • Descriptive-based • Process-based • 1. Dynamic classification scheme • * Active • * Passive • * Dead • 2. Thermal classification scheme • * Temperate Glaciers

32. IV. Classification of Glaciers • Descriptive-based • Process-based • 1. Dynamic classification scheme • * Active • * Passive • * Dead • 2. Thermal classification scheme • * Temperate Glaciers • * Polar Glaciers • --sub polar • --high polar

33. V. Erosional Glacial Landforms

34. Cirques Tarn Lakes Pater Noster Lakes Horns Aretes U shaped Valleys Hanging Valleys Fjords

35. Cirques

36. Arete

37. U-shaped valley

38. Horn

39. Fjords

40. VI. Depositional Landforms Moraines Lateral Medial

41. VI. Depositional Landforms Glacial Till Stratified drift

42. Lateral and Medial Moraines

43. Moraines……End, Terminal, Ground

45. End Moraine

47. Terminal moraine

48. Eskers, Drumlins, Kames, Kettles, Outwash Plains, Erratics

50. Drumlin