Survey Maps New G43 S_7, S_10.pdf grade. 10 icse geography

1. SURVEY MAPS
• Topographical maps are Large scale maps show detailed study
of a small area that combine natural and man-made features.
They show relationship between physical features & man made
features.
• Topographical maps are also known as Ordnance Survey Maps
and are similar to the Physical maps as it shows different
landscape features.
• It is an important tool for geographers who intend to make an
in-depth study of a region.These maps are crucial for the army
and defense services as the type of terrain will determine their
strategies. A.Sharma.

2. Map No G43 S/7
The new map numbering is
based on IMW ie. International
Map of the World.
It starts from equator so India
series lies from C as A begins
from equator.
The number G denotes
Rajasthan Abu district has 24
squares where each square is
further subdivided into 16
squares
Maps G43 S/7 and G43 S/10

3. G 43 S /10

4. G 43 S/7

5. COLOURS IN THE TOPO SHEET.
Apart from the
conventional signs and
symbols different
colours are used to
show distributed of
different topographical
features and land use.

6. COLOURS
The conventional signs
and symbols represent
relief features and
human activities.
Besides these certain
hindi terms are also
seen in the
topographical maps.

7. COMPASS DIRECTIONS
Directions form important element of a
map. Total we have 8 Cardinal directions.
The four points North,South,East & West
are known as Cardinal Points.
Another set of four directions between
these cardinal points are:
North-East (NE)
South-East (SE)
North-West (NW)
South- West (SW)

8. DIRECTIONS
A What is the compass direction of
A from B.
ANS- ?
B What is the compass direction of
B from A.
ANS- ?

9. GRID REFERENCE
The National Grid system (Vertical & Horizontal lines)
used in Topographical maps consists of network of
lines on topographical sheets running from north to
south as Eastings and east to west as Northings.
These lines are Red in colour.
In a map two figure eastings and northings are
printed at intervals of 1 km along the north and east
edge of the map.

10. GRID REFERENCE

11. GRIDS
Northings
●Horizontal lines running from east to west are
called northings since they indicate a distance north
of the origin of the grid reference.
●Northing increase numerically as we go northwards.
●Northings are always quoted after the Eastings
when giving a grid reference.

12. GRIDS
Grids are used to identify locations
A four figure grid reference helps to identify area.
A six figure grid reference helps to identify location.
Eastings-
●Vertical lines running from north to south are called
eastings since they indicate a distance east of the
origin of the Grid reference.
●Eastings are always quoted first.

13. FOUR FIGURE GRID REFERENCE
NORTHINGS EASTINGS

14. GRIDS
Four Figure Grid Reference
The first two figures are the
eastings and the last two
figures are the northings. The
crossing point of the eastings
and the northings is taken as
the originating point.

15. DRAINAGE PATTERN
• Dendritic pattern -The tributaries join the main river to form a pattern
like a tree with branches.
• Radial pattern- It is seen in highland region where rivers radiate from
the central point in all directions.
• Trellis pattern- In this pattern the stream flows parallel to each other
and then join the main river at right angles.
• Disappearing pattern- This indicates dry conditions , the streams flow
over sandy soil and suddenly disappear underground. Intermittent
• Intermittent pattern- The streams in sandy area disappear and again
reappear shown as dash lines

16. DENDRITIC PATTERN

17. RADIAL PATTERN

18. TRELLIS PATTERN

19. Seasonal stream with a
channel of water. Seasonal stream

20. DISAPPEARING
/INTERMITTEN
T PATTERN

21. Scales
• R.F= Distance on the Map_______________
Distance on the ground in the same unit
• Graphical/ linear scale- A straight line is divided into equal parts
(primary and secondary divisions) to show the marking represents
on the actual ground.

22. SCALES
• Scale= ratio of map distance of any two points to the
corresponding ground distance of these two points.
• Types of scale:
• Verbal/ statement scale- 2cm to 1 kms in this, the Scale is
expressed in words as a statement.
• Representative fraction- R.F -1: 50,000 so 1 unit map distance is
equivalent to 50,000 units on the ground.

23. SETTLEMENT PATTERN
Settlement pattern refers to the arrangement of
houses and other buildings in an area as seen
from above.
• Nucleated settlement- The houses are closely
spaced or clustered together.It can be called
compact too.

24. NUCLEATED SETTLEMENT

25. SETTLEMENT PATTERN
• Linear settlement- Houses are usually stretched
out along a road,river or railway line.
• Scattered/ dispersed settlement- It is generally
found in rural areas where population is sparse
so houses are scattered over a large area.

26. SCATTERED /DISPERSED PATTERN

27. LINEAR SETTLEMENT

28. HEIGHT
Contours- Lines that join places with same height above mean sea
level.
Contour Interval- The difference in height between two consecutive
contours.
Spot height- .520 It indicates height of the point above mean sea
level. The dot with number is written in black. .200
Triangulated height- It is the point that is accurately surveyed and
calculated shown as triangle 340 the mountain peak is indicated
this way..Δ 200
Bench Mark- A bench mark is written as BM and followed by a
number. It is etched in stone or also shown in the building to indicate
accurate height and serves as a reference for the surveyors. . . BM
633 . BM 63

29. Height
Relative Height- The relative height is written as ‘r’ with a
number indicating the relative height of the feature for eg 10r
against a sand dune means the relative height of the sand
dune is 10 metres to the surrounding area.
A.Sharma

30. TRANSPORT
Every settlement is connected by a mode of
transportation.
A topo sheet depicts railway lines in black with braod
gauge and metre gauge. Other roadways are in red
colour.

31. Transport-metalled, unmetalled/cart-track/pack track/footpath