Read topographic and geologic maps

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. Read this first

   Use this

   Card:

2. 1.

   A map has a 20 ft contour interval. Ari sees a hill whose innermost closed contour is labeled 640 ft. Where is the hilltop?

   • Exactly 660 ft, one interval up
   • Between 640 and 660 ft
   • Exactly 640 ft, the innermost line
   • Between 620 and 640 ft
3. 2.

   The heavy labeled lines on Esme's map read 500 and 600 ft, with 4 thin lines between them. What is the contour interval?

   • 25 ft, found by dividing 100 by the 4 thin lines
   • 4 ft, found as the number of thin lines
   • 20 ft, since 5 steps make 100 ft
   • 100 ft, the gap between the two heavy lines
4. 3.

   Elevations rise toward the north. Contour lines cross a valley in V's that point north, and the numbers rise to the north. Which way does Jun's stream flow?

   • South, away from the points of the V's
   • It does not flow, since V's mark a ridge
   • North, toward the points of the V's
   • East, across the V's
5. 4.

   A narrow strip on Kira's map has contour V's that point downhill, toward the lower numbers. Is it a ridge or a valley?

   • A ridge, since V's point toward the stream
   • A valley, since V's point upstream
   • A valley, since it is narrow and has a stream
   • A ridge, since its V's point downhill
6. 5.

   A stream on Luz's map crosses the 800, then 780, then 760 ft lines in that order. Which way is it flowing?

   • Toward the 800 ft line, which is uphill
   • Toward the 800 ft line, since it began there
   • Toward the 760 ft line, which is downhill
   • Along the 780 ft line, without changing height
7. 6.

   Map scale 1:24,000, so 1 cm on the map matches 24,000 cm on the ground. Milo's map has a scale of 1:24,000. How far on the ground is 1 cm on the map?

   • 2,400 m, found by dividing by 10
   • 24 m, found by dividing by 1,000
   • 240 m, found as 24,000 cm ÷ 100
   • 24,000 m, found by keeping centimeters as meters
8. 7.

   Map scale 1:24,000, where 1 inch on the map is 2,000 feet on the ground. Two points are 2 inches apart on Noah's 1:24,000 map, where 1 inch is 2,000 ft. How far apart are they on the ground?

   • 48,000 ft, found as 2 × 24,000
   • 2,000 ft, the length of just one inch
   • 4,000 ft, found as 2 × 2,000
   • 1,000 ft, found as 2,000 ÷ 2
9. 8.

   Rise 100 feet; run 500 feet; slope = rise ÷ run. A trail rises 100 ft over a ground distance of 500 ft. What slope does Pia get as rise ÷ run?

   • 0.5, found as 100 ÷ 200
   • 0.2, or 20%
   • 0.02, found by dropping a zero
   • 5, found as run ÷ rise

10. 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.

11. 9.

    Tala reads the legend of map G. Which rock unit is the youngest?

    • Qal, the Quaternary alluvium
    • Xg, since it is in the corner of the map
    • Jm, since green is the youngest color
    • Ks, since it lies farthest north
12. 10.

    On map G, dike d cuts Xg and Pl but ends at the Jm contact. Zee asks whether d is older or younger than Jm.

    • Younger: dikes are igneous, and igneous rock is newest
    • The same age: d and Jm touch along the contact
    • Older: Jm lies across the end of d, so d was there first
    • Younger: it cuts older rocks, so it is the youngest