objective: interpret topographic maps.. the study of the shapes and features of the earth’s...
TRANSCRIPT
Objective: Interpret topographic maps.
Topography
THE STUDY OF THE SHAPES AND FEATURES OF THE EARTH’S SURFACE.
TOPOGRAPHY
SHOWS THE THREE DIMENSIONAL SHAPE AND ELEVATIONS OF AN AREA OF LAND IN TWO DIMENSIONS
TOPOGRAPHIC MAP
HEIGHT ABOVE SEA LEVEL
ELEVATION
LINE THAT CONNECTS PLACES ON A TOPOGRAPHIC MAP THAT ARE ALL AT THE SAME ELEVATION (eventually a closed loop)Label the contour lines on your map.
CONTOUR LINE
Contour line
THE VERTICAL DIFFERENCE IN ELEVATION BETWEEN NEIGHBORING CONTOUR LINES
Label the contour line interval on your map.
CONTOUR LINE INTERVAL
contour line interval
CONTOUR INTERVALS
INDEX CONTOURS
THE DIFFERENCE BETWEEN THE HIGHEST ELEVATION POINT AND THE LOWEST ELEVATION POINT ON A MAP
RELIEF
200 300
400
Units = feetWhat is the relief of this map? What is the contour interval of this map?
CONTOUR LINES ARE CLOSELY SPACED ON STEEP SLOPES.
CONTOUR LINES ARE WIDELY SPACED ON GENTLE SLOPES.
TOPOGRAPHIC MAP RULES
Contour linesLINES CLOSE
TOGETHER - STEEPER LINES SPACED OUT - < STEEP
WHERE A CONTOUR LINE CROSSES A STREAM OR VALLEY, THE CONTOUR LINE BENDS TO FORM A “V” THAT POINTS UPSTREAM.
In the upstream direction, the successive contours represent higher elevations.
Topographic Map Rules
OTHER FEATURES
CONTOUR LINES NEAR THE TOP OF A HILL FORM CLOSED, CIRCULAR SHAPES.
The top of the hill is higher than the highest closed contour line.
Topographic Map Rules
DEPRESSIONS WITHOUT OUTLETS ARE SHOWN BY CLOSED HATCHED CONTOURS. The contour lines have short lines on the inside that are pointing down slope. The bottom of the depression is lower than the lowest closed contour line.
Topographic Map Rules
DEPRESSIONRINGS W/ SHORT LINES POINTING CENTER
Map Rules Contour lines do
not cross – height interval
changed evenly
WIDE spaced contour lines
= GENTLE slope
CLOSE spaced contour lines =
STEEP slope
Series of concentric rings
= rise in elevation
DOTTED lines =
river
Rings w/ short lines pointing center =
DEPRESSION
Index contour = 5th
line
200
250
A MAP MADE OF PICTURES OF THE EARTH TAKEN FROM A SATELLITE ORBITING THE EARTH.
Satellite Map
Aral Sea in central Asia