Post on 08-Jul-2016
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Basic ReferenceBasic ReferenceCertificate Geography Revision Certificate Geography Revision Exercises –Exercises –Issues & Map-Reading P.49-76Issues & Map-Reading P.49-76
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)
A
B
A: 340m
B: 80m
Gradient: 1 in HD/VDHD: measured actual length of the red line is 7.5cmMap Scale is 1 : 20000Actual Distance:(7.5 X 200)m = 1500mVD: 340m – 80m =260m Gradient: 1 in 1500m/260m= 1 in 5.8