1. Fluvial Processes

2. I. The Hydrologic Cycle 1)Precipitation

3. The Hydrologic Cycle 2)Evaporation-Transpiration

4. The Hydrologic Cycle 3)Infiltration

5. The Hydrologic Cycle 4)Runoff

6. II. Water Distribution A.In Virginia * annual rainfall: 43”

7. II. Water Distribution A.In Virginia * annual rainfall: 43” * Appalachian Plateau: 51”

8. II. Water Distribution A.In Virginia * annual rainfall: 43” * Appalachian Plateau: 51” * Coastal Plain: 55”

9. II. Water Distribution A.In Virginia * annual rainfall: 43” * Appalachian Plateau: 51” * Coastal Plain: 55” * Shenandoah Valley: 34-37”

10. II. Water Distribution A.In Virginia yearly variation…….

11. II. Water Distribution A.In Virginia yearly variation……. YEARTotalRunoffETInfilt.

12. II. Water Distribution A.In Virginia yearly variation……. YEARTotalRunoffETInfilt. 195643”15”25”3”

13. II. Water Distribution A.In Virginia yearly variation……. YEARTotalRunoffETInfilt. 195643”15”25”3” 194957”26”25”6”

14. II. Water Distribution A.In Virginia yearly variation……. YEARTotalRunoffETInfilt. 195643”15”25”3” 194957”26”25”6” 193030”5”28”-3”

15. II. Water Distribution A.In Virginia yearly variation……. YEARTotalRunoffETInfilt. 195643”15”25”3” 194957”26”25”6” 193030”5”28”-3” ET remains ~ constant

16. II. Water Distribution 1.36 billion cubic km of water 97.2%oceans 2.15% glacial ice 0.65% lakes, streams, ground water

17. III. Stream Flow A. Terms

18. III. Stream Flow A.Terms 1. Laminar vs. Turbulent

19. III. Stream Flow A.Terms 1. Laminar vs. Turbulent

20. III. Stream Flow A.Terms 2. Velocity, Area, Discharge

21. Water Velocity

22. Area

23. Discharge

24. Discharge = Velocity x Area

25. Discharge Discharge = Velocity x Area Q = V x A

26. III. Stream Flow A.Terms 3. Gradient

27. III. Stream Flow A.Terms 3. Gradient Rise =Vertical drop of the stream RunHorizontal Distance

28. Rise =Vertical drop of the stream RunHorizontal Distance

29. III. Stream Flow B. Downstream Trends 1. gradient 2. width and depth 3. discharge 4. velocity

30. III. Stream Flow B. Downstream Trends a. gradient  b. width and depth c. discharge d. velocity

31. III. Stream Flow B. Downstream Trends a. gradient  b. width and depth  c. discharge d. velocity

32. III. Stream Flow B. Downstream Trends a. gradient  b. width and depth  c. discharge  d. velocity

33. III. Stream Flow B. Downstream Trends a. gradient  b. width and depth  c. discharge  d. velocity 

34. C. Work of Running Water 1. Erosion * Sheet flow

35. C. Work of Running Water 1. Erosion * Sheet flow * Rill flow

36. C. Work of Running Water 1. Erosion * Sheet flow * Rill flow * Stream (gully) flow

37. C. Work of Running Water 2. Transportation a) dissolved load

38. 2. Transportation a) dissolved load b) suspended load

39. 2. Transportation a) dissolved load b) suspended load c) bedload

40. c. Bed load – i. Rolling ii. Sliding iii. Saltation

41. Saltation

42. IV. Features of Streams

43. A)Waterfalls and Rapids

47. IV. Features of Streams B)Meanders

48. Pointbars Cutbanks

49. IV. Features of Streams C)Pointbars

50. IV. Features of Streams D)Cutbanks

51. IV. Features of Streams E. Oxbow lakes

52. IV. Features of Streams E) Oxbow lakes

53. IV. Features of Streams Oxbow lakes (Cont’d)

54. IV. Features of Streams Oxbow lakes (Cont’d)

55. IV. Features of Streams F) Braided Streams

56. IV. Features of Streams G) Natural Levees

57. IV. Features of Streams H) Deltas

58. IV. Features of Streams H) Deltas

59. IV. Features of Streams I) Floodplains and Terraces

62. V. The Drainage Basin A. Overview….

66. B. Stream Ordering

67. Stream Ordering Strahler (1952) (after Horton, 1945) Shreve (1967)

68. Strahler (1952) (after Horton, 1945)

69. Shreve (1967)

70. Bifurcation ratio (Rb) streams of one order streams of the next highest order Ex: 1 6 th order stream 3 5 th order 9 4 th order27 = 3 27 3 rd order9 81 2 nd order Ratio value is nearly constant between adjacent orders AND….where geology is homogeneous, Rb = 3.0 – 5.0

71. C. The Hydrograph 1. General

72. C. The Hydrograph 1. General 2. The Storm Hydrograph

74. C. The Hydrograph 1. General 2. The Storm Hydrograph a. Shape and distribution of events

75. direct ppt., runoff, baseflow, interflow

79. Comparing the characteristics of flashy and sluggish hydrographs

80. VI. Flood Frequency

82. What does this mean???

83. What does this mean??? the curve estimates the magnitude of a flood that can be expected within a specified period of time

84. What does this mean??? the curve estimates the magnitude of a flood that can be expected within a specified period of time The probability that a flow of a given magnitude will occur during Any year is P = 1/RI.

85. What does this mean??? the curve estimates the magnitude of a flood that can be expected within a specified period of time The probability that a flow of a given magnitude will occur during any year is P = 1/RI. EX: a 50 year flood has a 1/50, or a 2 percent chance of occurring in any given year

86. For multiple years: q = 1- ( 1-1/T) n where q = probability of flood with RI of T with a specified number of years n

87. For multiple years: q = 1- ( 1-1/RI)n where q = probability of flood with RI with a specified number of years n EX: a 50 year flood has an 86% chance of occurring over 100 years

88. “Other Topics” Channelization

93. Rise = vertical drop Run horizontal distance

94. Channelization

99. Tomorrow’s excursion to South River……. COURSES PHYSICAL GEOLOGY (GEOL 110)GEOMORPHOLOGY (GEOL 385) FIELD GEOLOGY (GEOL 399) TOPICS IN GEOMORPHOLOGY