Map and Route Analysis Flashcards

On a topographic map, contour lines that are spaced very close together indicate:

Answer: A steep, rapid change in elevation

Closely spaced contour lines represent rapid elevation change, meaning the terrain is very steep.

A map scale of 1:24,000 means that one inch on the map equals how many feet on the ground?

Answer: 2,000 feet

At 1:24,000 scale, one inch equals 24,000 inches on the ground, which converts to 2,000 feet.

Which map symbol typically represents a perennial (year-round) stream on a USGS topographic map?

Answer: A solid blue line

Solid blue lines represent perennial streams that flow year-round on USGS topographic maps.

When planning a wilderness route, a drainage divide (ridgeline) on a topographic map is best identified by:

Answer: Contour lines that form U-shapes pointing uphill

Ridgelines appear as U-shaped contour lines opening toward lower elevations, indicating high ground between drainages.

A valley or drainage on a topographic map is identified by contour lines that:

Answer: Form V-shapes pointing uphill toward higher elevation

Valleys appear as V-shaped contour lines with the V pointing toward higher elevation (uphill).

What is the primary purpose of a map legend (key) when analyzing a route?

Answer: To explain the symbols, colors, and features shown on the map

A map legend decodes the symbols and colors used on the map so the reader can correctly interpret terrain features.

When calculating total route distance on a 1:24,000 scale map, you measure 3.5 inches along a trail. What is the approximate ground distance in miles?

Answer: About 1.3 miles

3.5 inches × 2,000 feet/inch = 7,000 feet, which is approximately 1.3 miles (5,280 feet per mile).