Read topographic and geologic maps
Grade 9 Science Worksheet - Challenge Me
Circle the best answer.
Close contour lines mean the rock is hard and resists erosion. A classmate says close contours mean the rock is hard and resists erosion. Ari replies. Which reply is strongest?
- Yes: close lines are drawn only where the rock is the oldest
- Yes: steep ground forms in hard rock, and that is shown by close lines
- No: close lines show steep ground only; rock type needs a geologic map
- No: close lines show flat ground, so the rock must be soft
Read this first
Claim
On a profile with vertical exaggeration 5, a hillside looks like a slope of 1.0, about 45 degrees. A friend says the real hillside is 45 degrees.
A profile has vertical exaggeration 5. A hillside looks 45 degrees. Bo's friend says the real hillside is 45 degrees. Which reply fits?
- No: the real slope is about 0.2, near 11 degrees, since 1.0 ÷ 5
- Yes: a profile shows the true slope of the ground
- Yes: 45 degrees is the usual slope of a hillside
- No: the real slope is about 5, since the profile flattens it
Use this
Geologic map G (made up). Legend, youngest to oldest: Qal, alluvium (Quaternary, yellow); Ks, sandstone (Cretaceous, olive); Jm, mudstone (Jurassic, green); Pl, limestone (Permian, blue); Xg, gneiss (Precambrian, gray). Xg lies in the southwest. Pl lies north of Xg and rests on it. Jm lies north of Pl, and Ks lies north of Jm. Dike d (diabase) cuts Xg and Pl and ends at the Jm contact. Alluvium Qal fills the stream valley and covers the edge of Ks. Fault f cuts Pl, Jm and Ks but not Qal.
A classmate says dike d on map G is the youngest feature, since it cuts two units. Esme checks the map. Which reply is strongest?
- No: Xg is younger than d, since Xg is gray and d is darker
- Yes: dikes are igneous, and igneous rocks form last
- No: d ends at the Jm contact, so Jm, Ks, f and Qal are younger
- Yes: a dike that cuts two units is younger than the other units
Card
Map scale 1:50,000, so 1 cm is 50,000 cm on the ground. Two points 4 cm apart are at 400 m and 600 m.
Two points are 4 cm apart on a 1:50,000 map, at 400 m and 600 m. What average slope does Jun get?
- 0.05, found as 200 m ÷ 4,000 m
- 0.001, found as 200 m ÷ 200,000 cm
- 10, found as 2,000 m ÷ 200 m
- 0.1, found as 200 m ÷ 2,000 m
a cliff rises 600 feet over 1,500 feet of ground. The profile has vertical exaggeration 4. A cliff rises 600 ft over 1,500 ft on the ground. A profile has vertical exaggeration 4. What does Luz get for the true and apparent slope?
- True 0.4; it looks like 1.6, four times steeper
- True 0.1; it looks like 0.4 on the profile
- True 1.6; it looks like 0.4 on the profile
- True 0.4; it looks the same, 0.4, on the profile
a map shows a stream with no flow arrow. Contour lines cross it. Milo must find which way a stream flows on a map with no arrows. Which evidence is strongest?
- The stream is blue, so it flows the way its label reads
- The V's point downstream, and the numbers rise along the stream
- Contour numbers fall along the stream, and the V's point the other way
- The north arrow points the way the water flows
Use this
Geologic map G (made up). Legend, youngest to oldest: Qal, alluvium (Quaternary, yellow); Ks, sandstone (Cretaceous, olive); Jm, mudstone (Jurassic, green); Pl, limestone (Permian, blue); Xg, gneiss (Precambrian, gray). Xg lies in the southwest. Pl lies north of Xg and rests on it. Jm lies north of Pl, and Ks lies north of Jm. Dike d (diabase) cuts Xg and Pl and ends at the Jm contact. Alluvium Qal fills the stream valley and covers the edge of Ks. Fault f cuts Pl, Jm and Ks but not Qal.
Pia claims fault f is younger than Ks on map G. Which evidence on the map supports that claim most?
- f cuts Pl, the oldest unit that it touches
- f cuts Ks, while Qal lies across f without a break
- f lies north of Pl, which is Permian
- f is a straight line, and straight lines are young
Card
Contours join equal elevations. The interval is the gap between neighboring lines. Close lines mean steep ground. V's in valleys point upstream. Contours do not show rock type.
Ren writes one summary of contour lines. Which one fits best?
- Lines of equal slope; close lines are steep, valley V's point upstream
- Lines of equal height; close lines are steep, valley V's point upstream
- Lines of equal height; close lines are flat, valley V's point downstream
- Lines of equal height; close lines are steep, and they show hard rock
Card
Ground distance = map distance × scale. Slope = rise ÷ run, with the same units. Feet per mile uses 5,280 feet. A stretched vertical scale makes slopes look steeper.
Tala writes one summary of reading slope from a map. Which one fits best?
- Scale to ground distance, then rise ÷ run, then divide by exaggeration
- Rise ÷ map distance, then multiply by the scale and exaggeration
- Scale to ground distance, then run ÷ rise, then multiply by exaggeration
- Rise ÷ run on the map in any units, then ignore exaggeration
Use this
Geologic map G (made up). Legend, youngest to oldest: Qal, alluvium (Quaternary, yellow); Ks, sandstone (Cretaceous, olive); Jm, mudstone (Jurassic, green); Pl, limestone (Permian, blue); Xg, gneiss (Precambrian, gray). Xg lies in the southwest. Pl lies north of Xg and rests on it. Jm lies north of Pl, and Ks lies north of Jm. Dike d (diabase) cuts Xg and Pl and ends at the Jm contact. Alluvium Qal fills the stream valley and covers the edge of Ks. Fault f cuts Pl, Jm and Ks but not Qal.
Zee writes one summary of how to order events on map G. Which one fits best?
- A feature is older than both what it cuts and what covers it
- A feature is older than what it cuts and younger than what covers it
- A feature is younger than what it cuts and older than what covers it
- A feature is younger than what covers it and what it cuts
