Map skills for grade 8 to 12

1. Mapwork

2. Otavi

3. Characteristic of a map
• Scale
• Title
• Legend/ Key/ Reference
• Direction

4. Types of Scale
Word Scale :
2 cm on the map represents 1 km on the ground or in
reality
Ratio Scale : 1: 50 000
Fraction scale:
1
50 0000
Linear Scale:

5. Determining size of the scale
• When determining size of ratio scale, you look at
how big is the number after the colon (:). If the
number is bigger than its shows a small scale but
if the number is smaller then it indicates big
scale.
• The number show how much detail and
information is indicated by the map. The bigger
the number the more information covered but
less detail, while smaller number means less
information but detailed
• Example, 1 : 50 000 is a small scale while
1 : 25 000 is a large scale

6. Measuring and calculating
distance on the map
1. Measure distance on map in cm.
2. When measuring a curve line you use a strip of
paper and when measuring a straight line use a
ruler.
3. Apply formula
Distance on map
unit asked (m or km)
× Scale
4. Unit asked in m divide by 100 and in Km divide
by 100 0000

7. Example How to calculate distance
For instance, the distance measured on the map between
two points is 5cm and the map scale 1: 50 000
• To kilometer (Km)
5cm
100 000 × 50 000 = 2.5 Km
1
2 x 5cm= 2.5 Km
• To meter (m)
5cm
100 × 50 000 = 2500 m

8. Converting scales to Another
(a) Ratio to fraction (Ratio scale, 1 : 50 000)
Expressed as a Normal fractional scale.
1
50 000
Express scale as half a fractional scale.
1
50 000 𝑥
1
2 =
1
100 000
Express scale as a double fractional scale.
1
50 000 𝑥 2 =
1
25 000

9. (b) Ratio to word scale (Ratio Scale,1:50 000)
1:50 000
1cm=50 000 cm
1cm=
50 000
100 000
1cm = 0.5km
1cm on the map represent 0.5km on the ground
or
1cm on the map represents 50 000 cm on the
ground.
2cm on the map represents 1km on the ground.

10. (c) From word scale to ratio scale.
word scale: 2cm on the map represent 1km on the ground
2cm=1km
2cm= 1km x 100 000
2cm=100 000cm
2𝑐𝑚
2
=
100 000cm
2
1cm=50 000cm
1:50 000

11. (d) From linear to word scale to ratio scale
First measure the segment of the scale in cm, e.g.
you get 2cm.
To Word scale
2cm= 1000 m
2cm on the map represents 1000m on the ground
2cm

12. To Ratio scale
2cm= 1000 m
2cm= 1000 x 100
2cm/2=100 000/2
1cm=50 000 cm
1: 50 000

13. Determining Height
• Height on the map is represented in metres (m)
Height on a topographic map is presented by:
Spot Height e.g. 1170
Trigonometrical Beacon e.g. 330
1274
 Contour lines

14. Calculating gradient
• Gradient refers to how steep is the slope
• A gradient of 1: 5 is steeper than the gradient
of 1:50.
• Reason: A gradient of 1:5 has to cover less
distance on the actual ground for 1 unit
increase in height While a gradient of 1:50 has
to cover more distance on the actual ground
for 1 unit increase in height.

15. How is gradient calculated
• Gradient=
Vertical interval (VI)
Horizontal interval (HI)
• VI= Highest height – Lowest Height
• HI =
Distance on the map
100 x Scale of the map

16. Example
Calculate the gradient between spot height
1174 and spot height 1274, on a topographic
map if the distance between them is 4cm. The
map scale is 1: 50 000.
VI = highest – lowest
VI=1274m - 1174m
VI= 100m

17. • HI=
Distance on the map
100 x Scale
• HI=
4𝑐𝑚
100 x 50 000
• HI= 2000 m

18. • Gradient=
Vertical interval (VI)
Horizontal interval (HI)
• Gradient=
100 ÷
2000 ÷
100
100
• Gradient =
1
20
• Gradient= 1:20 (Change fractional scale into
ratio scale)

19. Direction
• Make use of sixteen compass directions.
Direction Web Cross

20. How to get direction
• Step 1: Connect the two features involved with
a light pencil
• Step 2: Draw a true north line on the starting
feature
• Step 3 : Draw a neat cross, on the starting point
• Step 4 : find the direction using the neat cross

21. Example
Find the direction of B from A.
• Mark the North line on
starting point at A
• Draw a direction neat cross,
on the starting point (at A)
A
B
x
x
• Draw the line connecting A
to B.
N
NE
E
SE
S
NW
SW
•Direction of B from A is
South East (SE)

22. Bearings
Rules:
• Are always written in three figures (e.g.
040° instead of 40°)
• Always measure the angle clockwise from
the True North

23. Matching compass points…
360°
000°
023°
045°
068°
090°
113°
225°
158°
180°
338°
315°
293°
270°
248°
135°
203°

24. Measuring bearings…
Find the bearing of B from A.
• Mark the North line on at A
(if there isn’t a North line
draw one in)
• Place your protractor over
the north line with 0° at the
top (true north).
A
B
x
x
• Draw the line connecting A
to B.

25. Measuring bearings…
Find the bearing of B from A.
•Measure the angle clockwise
from the North line to B
• Give the answer as a three-
figure bearing
The bearing of B from A is 134°.
A
B

26. Measuring bearings…
Find the bearing of A from B.
• Mark the North line on at B
(if there isn’t a North line
draw one in)
• Measure the angle
clockwise from the North line
to A
A
B
x
x
• Draw the line connecting B
to A.

27. Measuring bearings…
Find the bearing of A from B.
• Place your protractor over
the north line with 0° at the
bottom.
• The angle has gone past
180° so you will need to add
your measurement to 180°
A
B
x
x
• Because you are measuring
clockwise you need to
measure the exterior angle.

28. Measuring bearings…
Find the bearing of A from B.
• The measurement from the
bottom 0° is 135°.
The bearing of A from B is 313°.
A
B
x
x
• 133° + 180° = 313°.
135 °

29. Determining location
• Involves using Latitude and longitude
• Latitude are line that runs from the west to the east
while Longitude lines that runs from north to the
south
Symbols used
• Degrees(°), minutes (‘) and seconds (“).
How to write Location( coordinates)
• In Southern Hemisphere we first write the latitude
degree, minutes, seconds reading follow by south
direction.
• Then followed by the longitude degree, minutes,
second reading followed by the east direction.
• 24°51’45’’S29°15’30’’E

31. Examples how to determine location?
Find location of A (see next slide)
a) In Degree and Minutes
• Latitude reading will be 17˚23 ̒S
• Longitude reading will be 19˚38 ̒E
• Therefore the Location will be
17˚23 ̒S 19˚38 ̒E

32. b) Degrees, Minutes and Second
For you to do this you need a ruler and
calculator.
See examples below

33. A
• Firstly connect latitudes
and longitudes lines to
make a grid
• For latitude seconds
measure from first
latitude to the second
latitude line in mm (b).
• Measure from first
latitude to the point in
mm (a).
• Use formalar
𝑎
𝑏
x 60”
• The final answer you
add it to degrees and
minutes of latitude

34. A
• Firstly connect latitudes
and longitudes lines to
make a grid
• For longitude seconds
measure from first
longitude to the second
longitude line in mm (b).
• Measure from first
longitude to the point in
mm (a).
• Use formalar
𝑎
𝑏
x 60”
• The final answer you
get add it to degrees
and minutes of
longitude

35. How to read other features on the map
Relief
• Look for region uplands and lowlands
• State the highest point and the lowest point,
• Recognize landform features such as Plateau,
Valley.
• Look for identifiable slopes – convex, concave,
steeper or Gentle.

36. Type of slopes on the map
Gentle : Steep

37. Terraced : Vertical

38. Convex : Concave

39. Terraced Slope

40. Flat Topped hill

41. Conical hill/Pointed butte

42. Spur

43. Valley

44. Saddle

45. Drainage
• Describe drainage density of river (High, Low or
Medium) depending on number of streams
forming a drainage
• Identify the drainage patterns (trellis, dendritic,
radial, etc.)
• Recognize if the rivers are perennial or not
• Recognizable features of the river (waterfalls,
rapids, braiding, meander, islands, ox bow lakes,
etc)
• Identify stage of river courses (upper, middle or
lower)

46. Drainage Patterns
Dendritric Pattern
Deranged Pattern

47. Parallel Pattern
Rectangular Pattern
Trellis Pattern

48. Radial Pattern

49. Drainage Density

50. Land use
A useful method is to consider economic activities:
Primary economic activities
a) Farming
• Type of farming: Arable Farming (Crop Farming)
or Pastoral Farming (livestock Farming)
• For Arable farming look out for cultivation,
irrigation furrows, canals and pipelines, farm
dams and Silos.
• For Livestock look out for kraals, windmills and
dipping tanks

51. b) Mining
• Open cast mining
• Look for name of the mine, Opencast mine, service
railways, mine dump, excavations and diggings.
c) Forestry
• Look out for plantations and forests names
d) Fishing
• Look out for coastal quays and harbours

52. Secondary economic activity
industry (look for industrial location factors,
market, raw material, power and water, labour, flat
land and transport).
Tertiary economic activity
Look for services facilities indicated next to each
service
• Education (School, University and Colleges)
• Recreation ( Caravan Park, Rec, Golf Course)
• Health /Medical service (Clinic and Hospitals)
• Shopping( Shops, Supermarkets and Store)

53. Transport and communication
• Railways
• Main Roads
• Secondary roads
• Landing Strips/ Airports
• Hiking and Trail

54. Road Patterns/Street Patterns

55. Photographs
• Horizontal photographs
• High oblique
• Low oblique
• Vertical /aerial photographs

56. Horizontal photographs
• Advantages
• The photograph shows a lot of detail
• Disadvantages
• Shows a small area
• Objects in the foreground block out objects in
the background
• Objects in the foreground appear larger than
objects in the background
• Cannot use them for map drawing

57. GROUND-LEVEL PHOTOGRAPH
Taken at ground-level, as you would normally
see things.

58. High oblique photographs
• Taken from a high vantage point such as top of a
building.
• The horizon is visible
Advantages
• Covers a larger area
• Shows a lot of information
Disadvantages
• Less detail in the foreground
• Objects in the foreground block out objects in the
background

59. HIGH OBLIQUE PHOTOGRAPH
Taken from a high point (building), horizon is
visible.

60. Low oblique photographs
• These photographs are taken from a airplane at a
angle.
• Horizon is not visible
• Advantages
• They show a larger area
• Shows much more information
• Disadvantages
• Objects in the foreground block out objects in the
background
• Objects in the foreground appear larger than
objects in the background

61. LOW OBLIQUE PHOTOGRAPH
Taken from an aero plane, horizon not visible.

62. Vertical photographs
• Taken from a airplane but the camera is tilted
vertically down.
• Advantage
• No hidden areas
• Shows a lot of information
• Used to draw maps
• Disadvantages
• Height and surface slopes are not easy to identify
• A lot of experience is needed to obtain
information from these photographs

63. Other Graphical analysis
Know how to read and complete the graphs below
• Bar graphs
• Line graphs
• Pie Chart
• Divided Bar graph
• Triangular graph
• Wind rose