Topographic Features L.O: STUDENTS WILL DESCRIBE HOW GRADIENT (SLOPES), HOLES & RIVERS ARE SHOWN ON TOPOGRAPHIC MAPS .

Do now: State the rules of contour lines and connect lines 5,15,25,35,45

Benchmarks (BM) – points whose exact elevation is recorded, even though they are NOT contour lines.

Exact Elevation of a Peak Exact elevations are shown by a X or a , followed by the elevation itself. Exact Elevation: 178 feet 178

Earth is NOT flat and smooth!

Earth has high places (mountains & hills) and flat places (plains).

Earth has“holes” & rivers in it!

A typical flat map cannot show Earth’s different elevations (hills, mountains, valleys etc)

L.O: SWBAT explain why we use topographic maps. Today, we will learn how different gradients (slopes), holes and rivers are represented on a topographic map L.O: SWBAT explain why we use topographic maps.

Hills and Mountains Contour lines that form closed circles indicate the presence of a hilltop or the peak of a mountain.

How many hills/mountains do you see?

mountains & hills have steep slopes “slope” (gradient): how tilted a landscape is. What do you notice? Flat plains or low hills have a gentle slope

gentle slope Steep slope

Closely Spaced Contours Steeper Slope (Gradient) – contour lines are closer together.

Gradual/Gentle Slope (Gradient) – contour lines are farther apart. Wide Spaced Contours Gradual/Gentle Slope (Gradient) – contour lines are farther apart.

Side View Top View (Map) Gentle Steep Gentle Slope

Widely separated contour lines show a gentle slope Close together contour lines show a steep slope. Widely separated contour lines show a gentle slope

Earth has holes in it!

Depressions Depressions are bowl-shaped indentions in the earth. (Ex. Craters, quarries) Special “hachured” contour lines (dashed lines )show these on a map. The elevation of the first depression contour is the same as the lowest regular contour near it. Meteor Crater – Arizona (NASA picture)

Each time you have another hatch mark you continue to go down in elevation!

Rules for Contours 5) The lowest possible elevation for a depression is “1” more than what the next contour “should” be. The lowest possible elevation of a depression is just above the value of  the next line that is not shown 90 90 51 80 70 60 50

100 100 50

Stream Flow Streams flow opposite the bend in contour lines. Streams always flow downhill!!! 400 ft 300 ft 200 ft 100 ft Hoh River – Washington State

The V’s bend (point) to where the river comes from. The river came from here!

DRAW ARROWS ON THE MAP TO WHERE THE STREAM 400 DRAW ARROWS ON THE MAP TO WHERE THE STREAM CAME FROM Hill 700 600 500 400 300 200 100 N S W E Ocean

Contour Lines Provide Important Information About: The shape of the land (Hills, valleys, etc.) Elevation The slope of the land (Steepness) The direction of stream flow THESE TOPICS ALWAYS SHOW UP ON THE REGENTS IN SOME FORM

LETS PRACTICE!!!!!!!!

Which side of this hill has a steeper slope? What evidence supports your answer? Which side of this hill has a gentler slope?

C 40 60 20 140 100 160 D 120 60 80 A 40 20 B Ocean N S W E 1 2 Miles

COMPLETE YOUR CROSSWORD PUZZLE THEN HAND IT IN!