If contour lines coalesce, the terrain is typically...

If contour lines coalesce, the terrain is typically...

• A. Steep
• B. Gentle
• C. Flat
• D. Undetermined

Answer: (A)

Contour lines show elevation, and how far apart they are tells you about slope. When lines coalesce, they become tightly packed, which means elevation is changing a lot over a short horizontal distance. That rapid change is what we call a steep slope. In contrast, lines that sit far apart indicate a gentle slope, and very few lines in a region often signal flat terrain. So the crowding of contour lines directly points to steep terrain.

Contour lines show elevation, and how far apart they are tells you about slope. When lines coalesce, they become tightly packed, which means elevation is changing a lot over a short horizontal distance. That rapid change is what we call a steep slope. In contrast, lines that sit far apart indicate a gentle slope, and very few lines in a region often signal flat terrain. So the crowding of contour lines directly points to steep terrain.