Rules of Contour Lines
Name_____________________ Date ________ Period _________
1. A contour line represents a single equal elevation: that is, all points on the same
contour line have the same elevation.
2. Where one closed contour line surrounds another, the inner contour line represents the
3. The elevation represented by a contour line is always a simple multiple of the contour
4. A contour line that closes within the limits of the map indicates a hill, ridge or plateau.
5. Commonly, every fifth contour line (index contour) is darker and its elevation is
6. On the same map, closely spaced contour lines indicate a relatively steep slope, widely
spaced contour lines indicate a relatively gentle slope, and uniformly spaced contour lines
indicate a uniform slope.
7. Contour lines do not cross other contour lines. Exception: on a vertical cliff or a
nearly vertical cliff, contour lines touch because they are on top of one another
8. Every contour line eventually closes against itself. However, the map area may not be
large enough to show this closure. Therefore, the contours will end at the edge of the
9. Closed depressions are shown by hachured contour lines. The hachures point into the
depression. (Hachures = short dashes)
10. A hachured contour line, lying between two different contour lines, is the same
elevation as the lower contour line.
11. Where two adjacent contours indicate opposite slopes (hachured contour next to
plain contour), both are the SAME elevation.
12. Where a contour line crosses a stream or valley, the contour bends to form a “V” that
points upstream or up the valley.
REVIEW: Day One
1. The difference in value between two contour lines is the ____________.
2. The zero contour line is ______________.
3. The line that is shaded darker than the other contour lines is the
4. A topographic map is _______________________________________.
5. The closer the contour lines, the __________ the slope; the father
apart the contour lines, the ___________ the slope.
REVIEW: Day Two
1. Contour lines form ____________ when they cross streams or valleys.
This _________ points __________ or ___________.
2. Closed depressions are shown by _____________________.
3. Every contour line eventually _______________________.
4. Gradient is _________________________. *First page of your ESRT*
5. A _____________ is a side view of a particular area.
6. The ________________________________ can be determined by
estimating the distance between contour lines
Working With Contour Maps
Figure A shows an island. Figure B shows a contour map of this island.
Answer the questions below by studying the contour map.
1. a) How long is this island? _______________________
b) The long part runs _______________________ (north and south, east or
2. a) How wide is this island? _______________________
b) The wide part runs _______________________ (north and south, east or
3. This island starts at sea level. How do you know? (Look only at the contour map.)
4. What is the contour interval of this map? _______________________
5. a) Which side of the island has the steepest slope _______________________
(north, south, east, west)
b) How do you know which side of the island is steepest?
6. a) Which side of the island has the gentlest slope? _______________________
(north, south, east, west)
b) How do you know which side of the island is gentlest?
7. How high is the peak of this island? _______________________
8. Compare the drawing of the island with the contour map.
a) Which one gives more information? _______________________
b) Which one is more accurate? _______________________
c) Which one is more useful? _______________________
9. By compass direction…
a) the _______________________ side of this landform has the steepest slope.
b) the _______________________ side of this landform has the gentlest slope.
10. The contour interval of this map is _______________________ meters.
11. The lowest elevation shown is _______________________ meters.
12. Which of these heights could be the exact elevation of the peak?
a) 520 meters b) 420 meters c) 475 meters
You can learn more from a contour map than just the shape and slope of the land.
Contour maps also tell you something about streams, “dips,” or depressions, in the land.
The head of a stream is the place where it starts. The place where it ends, in a lake or
ocean, is called the mouth. Look at the figure below for the following questions.
13. What letter is at
a) the head of the stream? _______________________
b) the mouth of the stream? _______________________
14. Where contour lines “cross” a stream, they _______________________
15. a) Everyone knows that water flows _______________________ (uphill, downhill)
b) In other words, water flow from a _______________________ (higher, lower)
elevation to a
_______________________ (higher, lower) elevation.
16. At a stream, contour lines seem to form “arrows.” Each “arrow” points…
a) toward the _______________________(head, mouth) of the stream.
b) _______________________ (upstream, downstream)
c) _______________________ (toward, away from) the direction of flow.
Making A Topographic Profile I
60 70 80 90
A 100 B
Making A Topographic Profile II
70 60 70
Making A Topographic Profile III
A 20 B
Rates and Gradients I
1. From your Handy Dandy Earth Science Reference Tables, what is the equation for
rate of change?
2. If the greenhouse effect causes the Earth's average temperature to increase by a
in degrees per year (ºF/year)?
3. After a series of earthquakes, a landsat satellite computes that California is 15 cm
less wide than it was 3 years ago. What is the rate of change of California's width?
4. As hurricane Felix neared the U.S. coast, air pressure dropped from 996 millibars to
980 millibars in 8 hours. Calculate the rate of air pressure change in mb/hour.
5. A category 5 tornado (very violent) passes over a hard core weather monitor. The air
pressure drops from 994mb to 988 in 3 minutes. What is the rate of change?
6. Which has a faster rate of air pressure fall, a hurricane or a tornado? (Hint: you have
to convert hours to minutes)
7. Erosion typically wears the Hawaiian volcano Mono Loa down about 20 cm in 5
years. Lava flows build the volcano up about 10 cm every time there is an eruption.
Mono Loa erupts about once every 2 years. Is the volcano growing or wearing down?
Rates and Gradients II
1. Write the equation for a gradient.
2. Write the equation for a rate of change.
3. If a mountain grows at a rate of 400 cm in 100 years, what is its growth rate per year?
4. Niagara Falls is worn down by 900 cm in a month. What is its erosion rate per day
(assume a month is 30 days long)?
5. A hiker gains 250 meters in altitude by climbing a mountain from the valley. The
peak is 5 km from the valley. What is the gradient of the mountain side?
6. The temperature from one side of a classroom is 27ºC while on the other it is 19ºC.
The distance between the two thermometers is 16 meters. What is the temperature
7. Two cities are separated by a distance of 500km. In one city, the barometric
pressure (air pressure) is 990mb, while the other city measures 1040mb. What is the
Red River Contours
1. What is the contour interval of this map?
2. Number all the contour lines.
3. What is the scale of miles of this map?
4. By means of the scale, measure the distance from the top of hill B to the top of hill A.
5. Which side of hill A has the steepest slope?
6. How can you tell whether a land form has steep or gentle slopes?
7. In what direction from hill A is hill B?
8. What is the elevation above sea level of hill A?
9. a) Which of the two hills is higher?
b) How much higher?
10. If you climbed to the top of hill B from C, how many feet would you climb?
11. In what direction is the Red River flowing?
12. How does a contour map show the direction in which a river is flowing?
13. Shade the area on the map which would be under water if the sea level rose 40 feet.
14. Calculate the gradient of the Red River from point D to the ocean?