basic mapping skill geography

1. MAPPING SKILLS

2. GRID READING
• The grid consists of Eastings ( _ ) and Northings ( I ).
• When finding something on the map (or recording somethings locations) one
must focus on the eastings first and then the northings.
• For Example 1 would be found at 18 (Eastings) and
45 (Northings).

3. GRID REFERENCES
• There are two types of Grid references (AKA Area References), 4 figure and 6
figure.
• A 4 figure GR will only show you the around about area of what you are locating,
which is mostly useful for road maps which are large scale (easier to read)
• For example, the blue square is at 62 33.
• A 6 figure GR will show you the exact location of what you are
looking for. This GR is most useful with a medium or small scale map as there is
more elements in each grid area and harder to read.
• For example, the dark blue square is at 625 333.

4. ANSWERS FOR SECTION C
• Four Figure GR
• A. 74 32
• B. 77 28
• C. 74 27
• D. 77 35
• Six Figure GR
• A. 745 325
• B. 779 281
• C. 741 279
• D. 775 350

5. LATITUDE
• Latitudes are the lines the run horizontally on a
globe or world map (not the grid on the map).
• The equator is the latitude that sits in the
middle sitting at 0 °.
• Each degree is divided into 60 minutes.
• The distance between each latitude is ~ 111km.
• Latitude lines are labelled by their degrees and
whether they are north or south of the equator.

6. LONGITUDE
• Longitude lines are called meridians and they are the lines that run vertical on a
globe or world map.
• The Meridian that passes through Greenwich In England is the prime meridian and
sits at 0°.
• The meridian lines run from 0 to 179 and are determined by either being East (right)
or West (left) of the Greenwich meridian.

7. LATITUDE AND LONGITUDE
• When reading a map using latitude and longitude, one must read latitude before
longitude (just like reading eastings before northings)
• The highest degree that latitude reaches is 90, so if the degree is higher then it is
for longitude.

8. MEASURING MINUTE AND SECONDS
• When using latitude and longitude on a map for coordinates, in order to pin
point an exact location, one must calculate the minutes and seconds after the
degree of Latitude and longitude (line the 6 figure GR).
• On a map, a number with a single quotation (e.g. 10’) represents that many
minutes (10 minutes. A number with a double quotation (e.g. 55”) represents
seconds (55 seconds).
• To calculate minutes and seconds of latitude, one must remember that the
distance between each degree is 111km which is also 60 minutes. This means that
1 minute (1’) is 1.85km, and 1 second is 3m (0.03km).

9. WORK THROUGH TOGETHER
• Using page 11 and the South Perth map, find the Latitude and Longitude degrees
and minutes of Byford, Thompson Lake and Churchman Brook Reservoir.

10. ANSWERS
• Byford sits at 32 13’ S and 116 01’ E
• Thompson Lake sits at 32 9’ S and 115 49’ E
• Churchman Brook Reservoir sits at 32 9’ S and 116 04’ E

11. SCALE
• On our South Perth Topographic map, the scale is set at 1:100 000, but what does
this mean?
• 100cm in 1m 100 000cm in 1km 1000m in 1km
• When measuring the scale with a ruler, one square equals 1cm, there for the scale
is 1cm:100,000cm (or 1cm:1km).
• Not all maps use cms as for their scale, so remember to check it every time you
are given a different map.
• When referring to the scale, one must not say ‘1 equals 100,000’, but ‘1 represents
100,000’.

12. CALCULATING DISTANCE
• Two types of distances you will have to calculate on a map:
• Straight line and
• Winding route
• You can measure a straight line distance easily by using a ruler and then calculate
it back to the scale of the map.
• For a Winding route distance, there are two different methods that can be used:
• Break the route down by measuring them in segments (measure each straight line and
plus them together) or,
• Measure the route using a piece of string and them compare the length with the scale
on the map.

13. TIME AND DISTANCE
• To calculate the time it takes to go a certain distance, the following formulaa
should be used.
𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒
𝑆𝑝𝑒𝑒𝑑
X
60 (𝑀𝐼𝑁𝑈𝑇𝐸𝑆)
1
= Time (in minutes)
• For example, if you are traveling at a speed ok 80kmph, and you have 300km till
you reach your destination, it will take
300
80
X
60
1
= 225min (3.75 hrs)

14. CALCULATING SPEED
• To calculate the average speed used to get from one point to aanother within a
specific time, we use the formula below:
𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑋 60
𝑇𝑖𝑚𝑒
= Speed
• To calculate the distance travelled, we use the following formula:
𝑇𝑖𝑚𝑒 𝑋 𝑆𝑝𝑒𝑒𝑑
60
= Distance

15. CALCULATING AREA
• To determine the total area of the map, you simply multiply the length of the map
(using the maps units and scale) by its width.
• Note: the answer for area will always be squared, e.g. 3𝑚2
• When measuring specific regions on a map, you simply:
• Count all the full squars
• Count the incomplete squares and half them
• Add them together, and then convert them into the scale and unit (make sure to square).

16. BEARINGS
• Bearings are a highly accurate method of giving a direction. A bearing is an
angulagr measurement from one place to another.
• Bearings are measured from North which is 0 degrees.
• Using a protractor, you can determine the bearings (direction) of one place to
another by lining your protractors 0 degree with the direction of north and then
working in a clockwise direction.
• To assist with bearings, draw a line or line up a ruler from the starting position to
the finishing position.

17. RELIEF
• Relief is the difference in height of features in a map.
• Maps use techniques such as:
• layer shading (the different coloured shading to represent different heights and
depths),
• Hachuring (tiny lines which vary in length and spacing to according to the
steepness of slope. Used in Cadastral maps).
• Hill or relief shading (creates a 3D view of the relief of an area. Shading is used to
create the impression of a light shining from above or northwest. Slopes on the
south east are darkened by shading, lower slopes are lightly shaded and plains
are left unshaded).
• Spot Heights (black dots with the height written next to it, giving the exact
altitude of a point.

18. CONTOUR
• Contour lines are another technique of relief.
• Contour lines join places of equal heights, the difference between each contour is
known as the contour interval (found near the scale and legend).
• Contour lines are continuous and may form closed circles, but they never cross
over and they can only touch
• when they represent vertical slopes.

21. SITE AND SITUATION
• Site is the physical features of the land on which the town or city is built and can
include:
• Height of the land (above sea level – ASL)
• Landforms
• Drainage (streams, confluence, swamps, lakes.
• Coastal features – river mouth, dunes, beach, tidal flats
• Situation is the locations of the town or city relative to to other urban centres in
its region.
• General statement of location, latitude and longitude – full length sentence- what it is and
where it is).
• Location in relation to towns
• Location to major transportation routes.