Page 12 - ICSE GEOGRAPHY

Elevation is given in
numbers such as 1193
and 1453 etc.

Contour lines that are
close together show a

steep slope.
Diff erent elevations
indicate an area’s relief
features.

A map showing the elevation, slope and relief of an area

Contour
Let’s Do
We have learned about various types of In the given map fi nd the slope between
maps till now. Out of all of them, only large- points D and G, assuming the scale of the
scale topographical maps have contours. map is 1:10,000, and the contour interval
Th e various types of contours and their is 25 metres.
characteristics are as follows.
Index contours: Th ese are contour lines 1250

which are traced in bold. Th e elevation is
written on them for reference. Th ey oft en
D G
occur in intervals of fi ve contour lines.

example, if there are two index contours of
300 and 400 metres, then there will be fi ve
intermediate contours if their interval is 20.
Contour interval: Th is is the diff erence in
Index contour lines
altitude between two successive contours.
Intermediate contours: Th ese are the lines Distance between contour lines indicate the
that lie between two index contours. For type of slope.

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