Which contour lines are typically labeled with elevation values?

Which contour lines are typically labeled with elevation values?

• A. Index contour lines
• B. Intermediate contour lines
• C. Supplementary contour lines
• D. Depression contours

Answer: (A)

Index contours are the bold lines on a topographic map that carry the elevation values. They’re thicker and usually labeled with the exact height, like the meters or feet above sea level, so you can quickly gauge elevations across the map. Between these labeled lines are the intermediate contour lines, which show elevations in between but are not labeled to keep the map from getting crowded. Supplementary contour lines are lighter or dashed lines added for detail in areas with gentle slopes and are typically not labeled. Depression contours indicate hollows or pits and may have special marks, but the standard reference elevations come from the index contours.

Index contours are the bold lines on a topographic map that carry the elevation values. They’re thicker and usually labeled with the exact height, like the meters or feet above sea level, so you can quickly gauge elevations across the map. Between these labeled lines are the intermediate contour lines, which show elevations in between but are not labeled to keep the map from getting crowded. Supplementary contour lines are lighter or dashed lines added for detail in areas with gentle slopes and are typically not labeled. Depression contours indicate hollows or pits and may have special marks, but the standard reference elevations come from the index contours.