S-130 Map and Compass 2 — Questions and Answers
Question 1: On a topographic map, what does a series of concentric closed contour lines indicate?
- A valley or drainage
- A hilltop or peak (Correct answer)
- A saddle between two ridges
- A cliff face
Correct answer: A hilltop or peak
Concentric closed contour lines represent a hilltop or peak, with the innermost circle being the highest point.
Question 2: Which map feature is used by wildland firefighters to identify potential escape routes and safety zones based on terrain?
- Legend symbols
- Contour lines (Correct answer)
- Grid coordinates
- Magnetic declination
Correct answer: Contour lines
Contour lines reveal terrain shape, allowing firefighters to identify ridges, saddles, and drainages critical for escape route planning.
Question 3: When orienting a map with a compass, what should align with the compass needle?
- The map's east edge
- The map's north edge (toward magnetic north) (Correct answer)
- The UTM grid lines toward true north
- The scale bar
Correct answer: The map's north edge (toward magnetic north)
Orienting a map means aligning the map's north edge with the compass needle pointing to magnetic north (after accounting for declination).
Question 4: What is the term for the angle difference between true north and the direction a compass needle points?
- Grid variation
- Magnetic declination (Correct answer)
- Bearing offset
- Azimuth shift
Correct answer: Magnetic declination
Magnetic declination is the angular difference between true (geographic) north and magnetic north shown by a compass.
Question 5: A firefighter reads a compass bearing of 315°. In what general direction is this?
- Southeast
- Northeast
- Northwest (Correct answer)
- Southwest
Correct answer: Northwest
315° on a compass corresponds to northwest (NW), located three-quarters of the way around from north in the counterclockwise direction.
Question 6: What does a dashed contour line typically represent on a USGS topographic map?
- A supplementary contour at half the contour interval (Correct answer)
- A trail or road
- An international boundary
- A stream or river
Correct answer: A supplementary contour at half the contour interval
Dashed (supplementary) contour lines represent elevation at half the standard contour interval to show subtle terrain features.
Question 7: In wildland fire operations, why is it important to know the contour interval of the map you are using?
- To calculate the map's age
- To determine how steep terrain is between contour lines (Correct answer)
- To find the nearest water source
- To identify fuel models
Correct answer: To determine how steep terrain is between contour lines
Knowing the contour interval lets firefighters estimate slope steepness — closely spaced lines with a large interval indicate very steep terrain.
S-130 Map and Compass 2
On a topographic map, what does a series of concentric closed contour lines indicate?