Read topographic and geologic maps
Grade 9 Science Worksheet
Circle the best answer.
Contour interval 20 feet. The outermost closed contour of a hill is 400 feet; the innermost is 640 feet. Ari counts closed contours on a hill. The outermost is 400 ft, the innermost is 640 ft, and the interval is 20 ft. How many lines is that?
- 14 lines, found by adding a line at each end
- 240 lines, found as 640 − 400
- 12 lines, found as (640 − 400) ÷ 20
- 13 lines, since (640 − 400) ÷ 20 is 12, plus 1
Read this first
Elevation along line A to A′ (made up)
Distance from A (miles) Elevation (feet) 0 1,200 0.5 1,280 1.0 1,520 2.0 1,820 2.5 1,600 3.0 1,400 Bo reads the elevation profile along A to A′. What is the relief along the line, from lowest to highest point?
- 620 ft, found as 1,820 − 1,200
- 1,820 ft, the highest elevation on the line
- 200 ft, found as the end (1,400) minus the start
- 300 ft, the biggest single rise between points
Card
a stream drops from 1,000 feet to 960 feet over 3 inches on a 1:24,000 map. 1 inch is 2,000 feet and 1 mile is 5,280 feet.
A stream crosses the 1,000 ft line, then the 960 ft line 3 inches away on a 1:24,000 map. What gradient does Esme find, in feet per mile?
- About 13 ft per mile, found as 40 ÷ 3
- About 0.007 ft per mile, found without 5,280
- About 35 ft per mile, from 40 ÷ 6,000 × 5,280
- About 3 ft per mile, found by using 1 inch = 24,000 ft
Profile horizontal scale 1 inch = 2,000 feet; vertical scale 1 inch = 400 feet. Kira draws a profile with a horizontal scale of 1 in = 2,000 ft and a vertical scale of 1 in = 400 ft. What is the vertical exaggeration?
- 1,600 times, found as 2,000 − 400
- 0.2 times, found as 400 ÷ 2,000
- 1 times, since both scales use one inch
- 5 times, found as 2,000 ÷ 400
Near point P the 1,000 foot contour bends into a V that points northeast. Elevations rise toward the northeast. Near point P, the 1,000 ft contour bends into a V pointing northeast, and heights rise to the northeast. Which way does Milo's stream flow?
- Southeast, as that is the way V's point on a ridge
- Southwest, away from the V's point
- Northeast, toward the V's point
- Northwest, along the 1,000 ft contour
Card
1:24,000 map, 1 inch = 2,000 feet. Stream M drops 60 feet over 1.5 inches. Stream N drops 40 feet over 0.5 inch.
Stream M drops 60 ft over 1.5 inches. Stream N drops 40 ft over 0.5 inch. Both are on a 1:24,000 map. Which is steeper, by Noah's slopes?
- Stream M, since it is longer on the map
- Stream M, since it drops more feet, 60 against 40
- The same, since the scale is the same for both
- Stream N: 40 ÷ 1,000 is 0.04, double M's 0.02
Card (USGS)
Valleys cut by streams make V's in contour lines; glacial valleys make U's. Contours here form a U with a wide, flat bottom.
Pia's contours run around a valley in a U shape with a wide, flat bottom. What does that suggest?
- A glacier may have carved it; glacial valleys make U's
- A stream cut it, since V shapes are the mark of glaciers
- A hilltop, since closed contours form U shapes on maps
- A ridge, since U shapes point downhill along the slope
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.
On map G, fault f cuts Pl, Jm and Ks but not Qal. Ren dates the fault. When did it move?
- Before Ks (Cretaceous), since Ks lies north of the fault
- Before Pl (Permian), since it cuts the oldest units
- After Qal (Quaternary), since faults cut any unit
- After Ks (Cretaceous) and before Qal (Quaternary)
On map G, what age range can Tala give for dike d?
- Younger than Ks (Cretaceous), since dikes are the newest
- Younger than Pl (Permian) and older than Jm (Jurassic)
- Older than Xg (Precambrian), since it cuts Xg
- The same age as Pl (Permian), since it cuts through Pl
On map G, Jm (Jurassic) lies directly on Pl (Permian). What does Zee infer about the Triassic?
- No Triassic rock is shown there, so a gap in the record is likely
- The Triassic is the same age as Jm, so it is mapped as Jm
- The Triassic is older than Pl, so it is part of the Xg gneiss
- Triassic rock is hidden under Jm, so nothing is missing there