Objectives

1. Objectives Describe how groundwater is stored and moves underground.

2. The Hydrosphere The water on and in Earth�s crust makes up the hydrosphere.

3. The Hydrosphere

4. Precipitation and Groundwater Evaporation of seawater introduces water into the atmosphere in the form of invisible water vapor and visible clouds.

5. Groundwater Storage Puddles of water that are left after a rain quickly disappear, partly by evaporating and partly by percolating into the ground.

6. Groundwater Storage Subsurface materials have porosities ranging from 2 or 3 percent to more than 50 percent.

7. The Zone of Saturation The zone of saturation is the depth below Earth�s surface at which groundwater completely fills all the pores of a material.

8. The Zone of Saturation

9. The Zone of Saturation Water in the zone of saturation can be classified as either gravitational water or capillary water.

10. The Zone of Saturation The Water Table

11. Groundwater Movement Groundwater flows downhill in the direction of the slope of the water table, squeezing through numerous tiny pores in the subsurface material.

12. Groundwater Movement Fine-grained materials typically have low permeabilities because their pores are so tiny.

13. Groundwater Movement Aquifers are underwater permeable layers where most groundwater flow takes place.

14. Section Assessment 1. Match the following terms with their definitions. ___ infiltration ___ porosity ___ water table ___ permeability

15. Section Assessment 2. Which of the following materials has the highest permeability? Explain why.

16. Section Assessment 3. Identify whether the following statements are true or false.

17. End of Section 1

18. Objectives Explain how groundwater dissolves and deposits rocks and minerals.

19. Groundwater Erosion and Deposition Most groundwater contains some acid, in most cases carbonic acid.

20. Dissolution by Groundwater The process by which carbonic acid forms and dissolves calcium carbonate can be described by three simple chemical equations.

21. Dissolution by Groundwater In the third process, the hydrogen ions react with calcium carbonate and dissolve it. CaCO3 + H+ � Ca2+ + HCO3�

22. Dissolution by Groundwater Caves

23. Dissolution by Groundwater Karst Topography

24. Dissolution by Groundwater Karst Topography

25. Groundwater Deposits Some tap water contains sulfur compounds, and some contains dissolved iron compounds.

26. Groundwater Deposits Hard Water

27. Groundwater Deposits Natural Deposits

28. Section Assessment 1. Match the following terms with their definitions. ___ sinkhole ___ stalactites ___ stalagmites ___ travertine

29. Section Assessment 2. Why do most caves form in limestone formations?

30. Section Assessment 3. What effect does hard water have on household plumbing?

31. End of Section 2

32. Objectives Relate the different types of springs to common systems of aquifers.

33. Groundwater Systems The average length of time that groundwater remains underground is several hundred years.

34. Springs Aquifers are permeable underground layers through which groundwater moves with relative ease.

35. Springs Emergence of Springs

36. Springs Emergence of Springs

37. Springs Temperature of Springs

38. Springs Temperature of Springs

39. Wells Wells are holes dug or drilled deep into the ground to reach a reservoir of groundwater.

40. Wells Overpumping of the well lowers the water level in it and produces a cone of depression in the water table around the well.

41. Confined Aquifers Water-table aquifers are unconfined and unprotected, and thus, they are easily polluted.

42. Confined Aquifers Artesian Wells

43. Confined Aquifers Artesian Wells

44. Threats to Our Water Supply Freshwater is Earth�s most precious natural resource.

45. Threats to Our Water Supply Overuse

46. Threats to Our Water Supply Subsidence

47. Threats to Our Water Supply Pollution in Groundwater

48. Threats to Our Water Supply Pollution in Groundwater

49. Threats to Our Water Supply Chemicals

50. Threats to Our Water Supply Salt

51. Threats to Our Water Supply Radon

52. Protecting Our Water Supply There are a number of ways in which groundwater resources can be protected and restored.

53. Protecting Our Water Supply Pollution plumes that are already in the ground can be monitored through observation wells and other techniques.

54. Section Assessment 1. Match the following terms with their definitions. ___ spring ___ geyser ___ recharge ___ drawdown

55. Section Assessment 2. Identify whether the following statements are true or false.

56. Section Assessment 3. What is a perched water table?

57. End of Section 3

58. Chapter Resources Menu Study Guide Section 10.1 Section 10.2 Section 10.3 Chapter Assessment Image Bank

59. Section 10.1 Main Ideas Some precipitation infiltrates the ground to become groundwater.

60. Section 10.2 Main Ideas Groundwater dissolves limestone and forms underground caverns. Sinkholes form at Earth�s surface when bedrock is dissolved or when caves collapse. Irregular topography caused by groundwater dissolution is called karst topography.

61. Section 10.3 Main Ideas The natural discharge of groundwater takes place through springs. Springs emerge where the water table intersects Earth�s surface.

62. 1. The major factor affecting the flow velocity of groundwater is ____. a. slope c. permeability b. gravity d. temperature Multiple Choice

63. 2. Which of the following is the most common acid found in groundwater? a. carbonic acid c. sulfuric acid b. calcium carbonate d. nitric acid Multiple Choice

64. Multiple Choice 3. What process adds water to the zone of saturation? a. drawdown c. subsidence b. incursion d. recharge

65. Multiple Choice 4. What is the type of stone that dripstone formations are composed of? a. karst c. breccia b. travertine d. shale

66. Multiple Choice 5. What is the cancer causing gas that can naturally pollute groundwater? a. chlorine c. radon b. nitrogen d. xeon

67. Short Answer 6. Why does the water table generally follow the topography of the land above it?

68. Short Answer 7. Why does salt water incursion occur?

69. True or False 8. Identify whether the following statements are true or false. ______ Less than three percent of Earth�s water  is freshwater. ______ Silt, clay, and shale are considered  permeable materials. ______ To be an artesian well, the well must have an  outlet below the pressure surface. ______ Poorly sorted sediments have a high porosity. ______ In the United States, industry uses more water  than agriculture.

70. Chapter 10 Images

71. Chapter 10 Images

72. Chapter 10 Images

73. Chapter 10 Images

74. Help

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