Barangay Council for the Protection of Children (BCPC) Orientation.pptx
Topography powerpoint
1. What is TOPOGRAPHY?
Topography is the physical and natural features of the land
A topographic map shows natural features (such as elevation)
and man made features (such as schools)
2. Contour Lines
The squiggly lines on a topographic map are called contour
lines
Contour lines are lines that represent a certain height or
elevation
All points on a contour lines are the same elevation
3. Contour Lines and Elevation
Imagine a picture of a
mountain and then imagine
there were lines drawn around
it every 20 feet
What would the mountain
with the lines look like if you
stood on the side of it?
What would the mountain
with the lines look like if you
were looking down on it from
an airplane?
4. Contour Lines and Elevation
The closer the contour lines are to each other, the steeper
the slope is!
5. Other Topographic Terms
Map scale – compares distances on the map with distances on
earth.
Legend – explains symbols used on the map.
Index contours – contour lines that are labeled to help you
find the contour interval.
Relief – the difference in elevation between any 2 points
A contour interval is the difference in elevation between two
contour lines that are side by side.
Remember that a contour interval is not the distance
between the two lines – to get the distance you need to use
the map scale.
6. Answer the Following…
Circle the map scale
Is there a legend?
Circle at least one
index contour
What is the contour
interval?
8. Depressions
A depression, such as the inside of a dead volcano, is
represented by Hachure lines.
Hachure lines are regular contour lines with small segments
sticking out from it.
The first hachure line is at the same elevation as the contour
line before it.
9. Streams
Streams are found in areas of low elevation
Streams are sometimes represented by a dark line
Contour lines form Vs that point upstream (toward higher
elevation)
The Vs point in the
opposite direction that
the water flows
10. Answer the Following….
What letter represents the
stream?
What type of elevation is
here?
Which way is the water
moving: to the right or to
the left?
11. Topographic Symbols
Mappers, also called cartographers use symbols to represent
certain things on a topographic map
For example, the color green represents an area with lots of
trees or vegetation
14. What landforms can be shown on a
topographic map?
Canyons – deep valleys with steep sides, often with streams
flowing through
River deltas – “end” of a river, where the river enters a
larger body of water
Mountains or hills – high elevation
Valleys/depressions – low elevation
Ridges – long, narrow elevation or chain of mountains
Contour lines are spaced far apart, so we know the elevation change is gradual. The “V” shapes suggest the formation of a river, which would be flowing FROM RIGHT TO LEFT. Upstream is to the east, downstream is to the west
Some of the lines are very close, indicating a steep incline. This is likely a canyon, formed by a river that is flowing FROM LEFT TO RIGHT.
This is a mountain – the highest elevation is in the middle (no hachure lines to indicate this is a depression). Likely there is a river flowing westward along the Vs, which seems to be creating a canyon. The southeastern slope is steeper than the northwestern slope.