morhpmetric analysis of a fluvial orginated drainage basin

2. :-
is the science that deals with quantitative
measurements of shape or geometry of any
natural form.
is the analysis of
different characteristics of basin (fluvially
originated), based on quantitative
evaluation of different parameters.
Area of land drained by a river and its
tributaries ,bounded by a watershed.

3. Basin Attributes

4. These Parameters are clubbed under the 3
aspects as:-
• Linear aspects (length ; related to
channel patterns)
•Areal aspects (area)
•Relief aspects. (relief i.e. Absolute &
Relative)
The concept was 1st initiated by Horton in
1932 and later diff. Geologist , hydrologist
and geomorphologist had contributed to it.

5. 1. To understand
 geological structure of underlying
rock
 geomorphological formations and
 hydrological chracterstics
Of a drainage basin
2. To find out the Geomorphological
basin control of flow and runoff..

6. 1. In watershed management
2. In identifying and planning the GW
potential zones.
3. In prediction of floods , their extent
and intensity.

7. I. Stream order
II. Bifurcation
ratio (Rb)
III.Stream
number (Nu)
IV.Length Ratio
(RL)
V. Length of
overland flow
(Lg)
VI.Sinuosity index
(SI)
I. Stream
frequency
(Sf)
II. Drainage
density (Dd)
III. Texture ratio
(Rf)
IV. Form factor
(Ff)
V. Elongation
Ratio (Re)
VI. Circulatory
Ratio (Rc)
VII. Constant of
Channel
Management
I. Basin relief
(R, H)
II. Relief Ratio
(Rh)
III.Dissection
Index (Di)
IV.Ruggedness
Index (Ri)
V. Channel
Gradient
ratio.
VI.Slope ()

8. Stream ordering
 Its
 Of determining of
the hierarchical
position of a
stream with in a
drainage basin
Stream order
 It’s
of a Stream
in the hierarchy of
tributaries, in a
drainage basin

9.  From trunk
stream to
fingertip stream
 From
fingertip stream
to Trunk stream
“Stream Segment method”
The hierarchical order increases only
when two stream segments of equal
order meet and form a junction.
No change in order if a lower order
stream joins a higher order stream.
No reclassification and renumbering
of streams required

10.  Addition of
two streams
(Irrespective of
the their order)
When Two similar
segments are combined,
they will be multiplied by 2
to form the next higher
order.
When the segments are
not similar, then simple
addition is carried out
Lowest order is 2

11. • Ratio b/w no of streams of higher order to lower order
• where
Nu=number of streams of given order, and
Nu+l =number of streams of next higher order.
• varies from 2 to 3or4 (2 in flat & rolling ; 3/4 in Mt. areas)
• Useful measure of flood proneness
• high bifurcation ratio indicates a high drainage density.
• total no. of streams in each order with in a basin
Nu = Rb(k-u)
• Where
Nu= number of stream segments of a given order
Rb= constant bifurcation ratio
u= basin order
k= highest order of the basin

12. •If the Rb is constant, the no of streams of
successively lower order tend to form a
Geometric series.
“Horton’s law of stream number”
•For ex:-
IF, Rb=4; Highest order stream =6
stream order (H-L)= 6,5,4,3,2,1
Stream number(Nu)= 1,4,16,64,256,1024
•The proportion of increase of mean lengths of stream
segments of two successive orders of the basin
RL= Lµ (mean length of all strreams of a given order)
Lµ-1
Lµ = ΣLµ (total stream length of a given order)
Nµ (total no of streams in that given order)

13. • Sinuosity is the degree of deviation of a river from
its expected straight path to its observed actual path
Channel sinuosity= OL (Observed path of stream)
EL (expected straight path of a stream)

14. (Sf)
 total no of
streams per unit
area, irrespective
of order
 Sf= Nu (total no of streams
of all orders
A (area of the basin)
(Nu)
 Linear aspect
 total no of streams of a
particular order

15. • expression of closeness or spacing of
channels within a basin
• Dd= Lu (total stream length of all orders)
A (Area of the basin)
•Low in Pt regions; High in Mt. regions
• Ranges from 0.55 to 2.09 km/km2

16. • product of Sf and Dd
•Rt=Nu( total no of streams of all orders)
• P ( parameter of the basin)
•Rt values
<2indicate very coarse,
2–4 coarse,
4–6 moderate,
6–8 fine,
>8 very fine drainage texture.
• Ff= A (area of basin LxB)
Lb2 (square of basin length)
•Values 0 (Elongated);
0.7854(perfect circular) ;
1 (near circular)
•Hence high value indicated More circular: low value indicated
more elongated

17. Re= diameter of circle with same area as basin
basin length
Value 0( max elongated) to 1 ( max circular)
• Re= 4A (Area of the basin)
P2 ( square of perimeter).
• Values 0 to1
• High , medium and low values indicate old, mature and
young stage of drainage basin

18.  Reciprocal of Drainage density (Dd)
 Expressed as required minimum area
for the maintenance and devt. of a
channel
 ↓ CCM indicates high flood
potentiality
 Low in Mt. ; High in Pt. regions

19. • Absolute relief (R) – Max altitude of a Basin
• Relative Relief (H) – Diff. b/w Min. and Max. altitude
• An indicator of erosional stage of a basin
• High in Mt-plain front
• Low in pt-plain front
Rh= H (Relative Relief in Km)
Lb (Basin length)
circular Basin → Rh↑
Elongated Basin → Rh↓
• Indicates overall steepness
• High in mt. than Pt. regions

20. Di= Relative relief (H)
Absolute Relief (R)
•It indicates the vertical erosion and dissected chr. of a
basin
•Range → 0 ( no vertical dissection; ex- pt.,plains)
1 ( max vertical dissection ; ex- mt.)
Ri = Dd × H
• Indicated the stage of geomorphic development of a
basin
• If, high→ young stage
Low Ri → old stage

21.  Determine infiltration V/S Runoff relation
 High→ Low infiltration and High runoff
 Gentle slope → high infiltration and low runoff.

22. over Quantification of a concept
(As quantitative and statistical
methods offer no substitute for
original thoughts.)
precise and accurate measurement
of complex landforms is highly
difficult and tedious task.
too much application of
mathematical equations

24. Basss kr naa yaar 🤦 😢