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Skills Worksheet
Directed Reading
Section: Water Beneath the Surface
1. When water seeps underground, it fills
between
rock particles.
2. The water below Earth’s surface is called
.
3. Groundwater is an important source of
in the
United States.
PROPERTIES OF AQUIFERS
4. What is an aquifer?
5. The percentage of the total volume of rock or sediment that consists of open
spaces is called
.
6. The amount of uniformity in the size of rock or sediment particles is
called
.
7. How do well-sorted and poorly sorted sediment differ in terms of their
particle size?
8. Loosely packed particles of rock have many open spaces, which results in
porosity.
9. Rock with tightly packed particles contains few open spaces, so it has
porosity.
10. In addition to sorting and particle packing,
also
affects porosity.
11. Generally, the more irregular the grain shape, the more
the rock or sediment.
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12. The ability of a rock or sediment to let fluids pass through its open pores, or
spaces, is called
.
13. For a rock to be permeable, the open spaces must
be
.
14. Sandstone is one of the most
rocks.
15. Because clay is composed of flat, fine-grained particles, it
is
.
ZONES OF AQUIFIERS
16. What pulls water down through rock and soil layers until it reaches a layer of
impermeable rock?
17. Define zone of saturation.
18. What does the term saturation mean?
In the space provided, write the letter of the description that best matches the
term or phrase.
______ 19. water table
______ 20. capillary action
a. the attraction of water molecules to
other materials
______ 21. capillary fringe
b. the upper surface of the zone of
saturation
______ 22. zone of aeration
c. the area in which water is drawn from
the zone of saturation
d. area between the water table and
Earth’s surface
23. How many regions does the zone of aeration have?
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MOVEMENT OF GROUNDWATER
24. Upon what does the rate at which groundwater moves horizontally depend?
25. Define gradient.
26. The velocity of groundwater increases as the water table’s
gradient
.
TOPOGRAPHY AND THE WATER TABLE
27. The water table generally mirrors the surface
.
28. List four factors that affect the depth of a water table.
29. What happens to water tables during times of prolonged rainfall?
30. What happens to water tables during times of drought?
31. How many water tables do most areas of Earth have?
32. What is a perched water table?
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CONSERVING GROUNDWATER
33. In many communities, the only source of fresh water
is
.
34. How long might it take for the water level in an aquifer to renew itself?
35. List three ways that a community might regulate the use of groundwater.
36. What is a recharge zone?
37. Why are recharge zones environmentally sensitive areas?
38. Name four ways that pollution can reach an aquifer.
WELLS AND SPRINGS
______ 39. A hole that is drilled to below the level of the water table and through
which groundwater is brought to Earth’s surface is called a(n)
a. well.
b. spring.
c. ditch.
d. artesian.
______ 40. A natural flow of groundwater to the surface where the water table
meets Earth’s surface is called a(n)
a. well.
b. spring.
c. hole.
d. artesian.
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______ 41. Ordinary wells work only if they penetrate
a. highly permeable sediment or rock.
b. the water table.
c. impermeable rock.
d. groundwater.
______ 42. Pumping water from a well lowers the water table around the well and
forms a(n)
a. ordinary well.
b. cone of depression.
c. ordinary spring.
d. drought.
______ 43. If too much water is pumped from a well, what might happen as a
result?
a. Nothing will happen.
b. The well and surrounding wells might go dry.
c. The well will refill.
d. A spring will form.
______ 44. Which of the following formations are usually found in rugged terrain
where the ground surface drops below the water table?
a. cones of depression
b. ordinary springs
c. ordinary wells
d. perched water tables
______ 45. When might an ordinary spring go dry?
a. when a nearby well goes dry
b. during the rainy season
c. during dry seasons or severe droughts
d. during periods of high winds
______ 46. An extensive aquifer through which water travels to a distant location
may become part of a(n)
a. ordinary well.
b. ordinary spring.
c. water table.
d. artesian formation.
______ 47. An artesian formation is a(n)
a. sloping layer of permeable rock between two layers of
impermeable rock.
b. aquifer at a recharge zone.
c. artesian well.
d. artesian spring.
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______ 48. In an artesian formation, the top layer of impermeable rock is
called the
a. artesian well.
b. aquifer.
c. recharge zone.
d. caprock.
49. When water enters the aquifer through the recharge zone of an artesian
formation, the weight of the overlaying water causes the pressure in the
aquifer to
.
50. Water can flow freely through a(n)
without being
pumped.
51. When cracks occur naturally in the caprock, water from an aquifer flows
through the cracks, forming a(n)
.
HOT SPRINGS
52. Groundwater is heated when it passes through rock that has been heated
by
.
53. Groundwater that has been heated to at least 37°C and then rises to the
surface of Earth before cooling produces a(n)
.
54. Mineral deposits around a hot spring create step-like terraces of calcite
called
.
55. When chemically weathered rock mixes with hot water from the spring, it
forms a sticky, liquid clay called a(n)
.
56. Mud pots that are brightly colored by minerals or organic materials are
called
.
GEYSERS
57. What is a geyser?
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58. What happens when the water in a geyser vent begins to boil?
59. How long will a geyser eruption continue?
60. What happens after a geyser erupts?
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ANSWER KEY
Directed Reading
33. groundwater
34. hundreds or thousands of years
35. monitor the groundwater level, dis-
SECTION: WATER BENEATH THE
SURFACE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
pores
groundwater
fresh water
An aquifer is a body of rock or sediment in which large amounts of water
can flow or be stored.
porosity
sorting
Most particles in well-sorted sediment
are about the same size. Poorly sorted
sediment contains particles of many
sizes.
high
low
grain size
porous
permeability
connected
permeable
impermeable
gravity
The zone of saturation is the layer of
an aquifer in which the pores are completely filled with water.
filled to capacity
B
A
C
D
three
The rate at which groundwater moves
depends on the permeability of the
aquifer and the gradient of the water
table.
Gradient is the steepness of a slope.
increases
topography
surface topography, permeability of
the aquifer, amount of rain, and rate of
water usage
The water table rises during times of
prolonged rainfall.
The water table falls and flattens
during times of drought.
one
When a layer of impermeable rock
sits on the main water table, a second
table called a perched water table
forms on top of the first.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
courage excess pumping, and recycle
used water
A recharge zone is anywhere surface
water can travel through permeable
rock to reach the water table.
Recharge zones are environmentally
sensitive because pollution in the zone
can enter the aquifer.
Answers may vary. Sample answer can
include four of the following: waste
dumps, underground toxic-waste storage systems, fertilizers, pesticides,
leaking sewage systems, salt water
from the ocean
A
B
A
B
B
B
C
D
A
D
increase
artesian well
artesian spring
magma
hot spring
travertine
mud pot
paint pots
A geyser is a hot spring that periodically breaks through a surface pool or
small vent with enough power to shoot
into the air.
The boiling water produces steam
that pushes the water above it to the
surface.
An eruption will continue until most of
the water and steam are emptied from
the vent and chambers.
After a geyser erupts, groundwater
continues to collect again and the
process is repeated, often at regular
intervals.
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