1. Tectonics, Geomorphology and Geologic Materials (The influence of the physical environment on watershed dynamics.) A Watershed Dynamics Tutorial © John F. Hermance February 9, 2003 (Images from Tasa Graphics among others) Contact information: Jack Hermance Environmental Geophysics/Hydrology Department of Geological Sciences Brown University, Providence, RI 02912-1846 Tel: 401-863-3830 e-mail: John_Hermance@Brown.Edu

2. Regional tectonics can play a controlling role in local watershed dynamics. (Images from Tasa Graphics cannot be used without permssion of the company.)

3. Plate tectonics drives current orogenic activity.

4. Orogenic activity is enhanced at plate boundaries.

5. How does the “rock cycle” determine local water decisions?

6. Understanding the evolution of geologic features, generically or on a site specific basis, can give insight into watershed processes, hence water-related decisions.

7. Igneous rocks

9. Understanding the evolution of geologic features, generically or on a site specific basis, can give insight into watershed processes, hence water-related decisions. Metamorphic rocks

10. Understanding the evolution of geologic features, generically or on a site specific basis, can give insight into watershed processes, hence water-related decisions. Sedimentary rocks

11. The Northwest US.

12. The “Rock Cycle” Exposed. The Northwest US.

14. Igneous rocks

15. Batholiths

16. Intrusive igneous rocks

17. Extrusive igneous rocks

18. Metamorphic rocks

19. Sedimentary rocks

20. The Northwest US.

21. The Western US. An Archetype Example

22. The Western US. Physiographic Landforms

23. The Western US. Basin & Range

24. The Western US. Colorado Plateau

25. The Western US. Snake River Plain

26. The Western US. Cascades

27. The Western US. Sierra Nevada

28. The Western US. Southern Rockies

29. The Western US. Northern Rockies

30. The Western US. Rio Grande Rift

31. The Western US. California Central Valley

32. The Western US. Southern Basin & Range

33. The Future (and the past).

34. The Oldest Bedrock: Shield Areas of the World.

35. “Basement”; then...

36. “Basement”; now...

37. Where or what is “basement”?

38. Evolution of the crust

39. Grand Canyon Exposure as a Microcosm of the North American Crust (From California to Massachusetts.)

40. Next. we’ll look at the shallow unconsolidated section.

41. We are interested in glacial features...

42. ... streambed features...

43. ... and fluvial deposits.

44. Sedimentary sorting.

47. (Back to metamorphism: Sediments are ephemeral.)

48. (Metamorphic Grade.)

49. A digression on glaciers.

50. The Ice Age

51. Maximum extent of glaciation.

52. “Fossil” glacial features.

53. (Moraines.)

54. Glacial landforms.

55. Glacial rebound.

56. Present day mountain glaciers (or not) as “keys to the past”.

58. Glacier in cross-section.

61. Stresses in a glacier crossing a rock step.

62. A tour of Canadian glacial forms.

63. The Athabasca.

64. A dry valley.

65. A hanging glacier.

66. A hanging glacier up-close.

67. A trip up the Athabasca. (Note principal features.)

68. The Ice Falls.

69. The Ice Falls on approach.

70. The Ice Falls on target.

71. This is why we came here.

72. (Radio waves through ice?)

73. This is why we came here. (Radio waves through ice? What does this have to do with NASA, and the Lunar Lander (Apollo Program)?)

75. “Fossil” glacial landforms.

76. Stream morphology.

79. Meanders.

80. Meanders - Flooded.

81. Meanders - Flooded - and buried.

82. Stages of stream evolution.

85. Deltas

87. Drainage patterns driven by bedrock patterns.

88. Current “geologic” processes can modify “current” hydrology.

89. Mass movement can modify local hydrology & vice versa.

90. Affect of subsurface water on mass movement.

95. Evolution of bedrock.

98. The paradigm for subsurface hydrology. Organic layer Leached layer Weathered bedrock Bedrock

99. Physiography of North America.

101. Groundwater regions of the US. (Note concordance with geology.)

102. End of Presentation (Tectonics, Geomorphology and Geologic Materials) © John F. Hermance; February 9, 2003 Go to Soil & Water.