Basic ReferenceBasic ReferenceCertificate Geography Revision Certificate Geography Revision Exercises –Exercises –Issues & Map-Reading P.49-76Issues & Map-Reading P.49-76

HKCEEHKCEEMAP READINGMAP READINGSKILLSSKILLS::

HKCEEHKCEEMAP READINGMAP READINGSKILLSSKILLS::

Basic Map Reading Skills:Check List Conventional Signs Grid References Scales Direction Gradient Cross-section & Relief Features

Conventional Signs Reference - WB:49

Conventional Signs Reference - WB:49

Conventional Signs Reference - WB:49

Conventional Signs Reference - WB:49

Conventional Signs Reference - WB:49

Conventional Signs Reference - WB:49

Grid References (WB:51-52)

to tell locations on a map two sets of lines

vertical – eastings (number values increase eastwards)

horizontal – northings (number values increase northwards)

grid square 4-figure location 6-figure

Grid References

Grid References(WB:53)

1132

147343

Scale (WB:54-55) to show the number of times that

the actual size of the ground has been reduced

helps us find out real distance / area from the map

Scale Statement Scale

describes the scale in words e.g. 1 cm to 200m

Representative Fraction (R.F.) shows scale in the form of a fraction / ratio e.g. 1:20000

Linear Scale uses a line to show the scale e.g.

Direction Reference – WB:59

Direction Reference – WB:59

Direction Reference – WB:60

Cross Section

Cross Section

Cross Section

Cross Section

Cross Section

Vertical Exaggeration Reference – WB:72

Vertical Exaggeration

Vertical Exaggeration

Relief Features Reference – WB:65-68

Relief Features

Relief Features

Relief Features

Relief Features

Relief Features

• gentle slope

• steep slope

• concave slope

• convex slope

• stepped slope

• spur

• valley

• hill

• ridge

• saddle

Gradient

Gradient

Gradient

Gradient

Calculate the Average Gradient of the Stream from A (source) to B (bridge)

Calculate the Average Gradient of the Stream from A (source) to B (bridge)

A

B

A: 340m

B: 80m

Gradient: 1 in HD/VDGradient: 1 in HD/VD

HD: measured actual length of the red line is 7.5cm

Map Scale is 1 : 20000

Actual Distance:

(7.5 X 200)m = 1500m

HD: measured actual length of the red line is 7.5cm

Map Scale is 1 : 20000

Actual Distance:

(7.5 X 200)m = 1500mVD: 340m – 80m =260m VD: 340m – 80m =260m

Gradient: 1 in 1500m/260m

= 1 in 5.8

Gradient: 1 in 1500m/260m

= 1 in 5.8