The document discusses drainage patterns, their classification, and significance. It outlines different types of drainage patterns including dendritic, trellis, rectangular, parallel, and radial patterns. Drainage patterns are influenced by factors like slope, rock type, geologic structures, climate, and geomorphic history. Improper drainage can lead to flooding while well-developed drainage increases water storage and supplies, supports irrigation, and affects groundwater potential and sustainability. Different drainage patterns reveal information about the underlying geology.

1. Drainage Pattern and Their Significance
Guided By
Dr. Govindaraju
Associate Professor
Department of Applied Geology
Submitted by
Avinash B R
II sem
Geo-Informatics

2. Drainage
Natural or artificial action of draining something or removal of surface or
subsurface water remove from an area. The typical shape of a river course as it
completes its erosional cycle is referred to as the Drainage Pattern of a
stream.
The drainage systems mainly depend upon the geological structure of the
region and the resistance of the erosion capacity of the rock to erosion.

3. Drainage patterns are controlled by following factors:
1) Initial slope.
2) Lithology and lithological variation.
3) Structures.
4) Geologic and geomorphic history of the area.
5) Climate and rainfall of the area

4. Outlined Characteristics to Classify
• Degree of integration
This element pertains to the degree of unity.it is an inductive of uniformity of
various characters and the presence of modifying factors.
• Density
The drainage density is already described is inductive of degree of erodibility
slope on which erosion occurs and special climatic conditions.

5. Cont.…..
• Degree of Uniformity
It is relatively homogeneity of pattern over an area.it indicates the boundaries
between the area of different characteristics and uniformity of erosional
history and the behaviour of the material of erosion.
• Orientation
It refers to direction and indicates the control and effects due to the presence
of geological factors like structural features and tectonic movements etc.

6. CONT….
• Degree of control
It is the most important feature in geological interpretation. The streams are
shaped by the tectonic features like folding, faulting, fracturing etc. The
tectonism products anomalies directional changes and adjustment which are
useful in tectonic analysis of a terrain.
• Angularity
It is abruptness of directional change furnished by the component streams of a
drainage pattern. These serve as guides for revealing the hidden features like
fractures, faults, shear zones and other features including underground
structures.

7. CONT….
• Angle of Junction
Normally we find an acute angle in the upstream direction between stream
and its tributary. It is a function of the channel slopes of two streams.

8. Consequent
• Are streams whose course is a direct consequence of the original slope of
the surface upon which it developed, i.e., streams that follow slope of the
land over which they originally formed
• Godavari, Krishna and Kaveri, descending from the Western Ghats and
flowing into the Bay of Bengal, are some of the consequent rivers of
Peninsular India.

9. Sub-sequent stream
• A stream that has developed on a weak substructure, such as a clay vale or in
regional joint or fault pattern, at right angles to streams consequent to the
dip of the slope.
• The Chambal, Sind, Ken, Betwa, Tons and Son meet the Yamuna and the
Ganga at right angles.

10. Obsequent stream
• A stream that flows in the opposite direction to a consequent stream,
often against the direction of dip.

11. Inconsequent drainage
• Which is unrelated to the structure of the rocks over which the rivers
flow. The show no relationship with the present structure and relief
and cut right through the line of highest elevations.

12. Antecedent Drainage
• The river which is follow the path or course of the mountain without any
modification in the topology. Drainage system where streams have
maintained their valleys across tectonic mountains and across them in deep
gorges are said to be antecedent because the river is older than or
Antecedent to the deformation responsible for the present structure and
relief. These drainages mostly found in regions of recent mountain
movements.

13. Superimposed Drainage
• A stream formed on one surface and structure has science cut down through
unconformity to flow over older rocks, which have structure discordant with
that above the unconformity. Such a stream is then said to be superimposed
on older rocks.

14. GEOMETRIC CLASSIFICATION
Dendritic Pattern - This is the most common pattern and is characterised by
tree like or fern like, irregular branching, haphazard orientation and irregular
spacing of the tributaries
Trellis Pattern - Trellised drainage patterns are formed by the network of
tributaries and master consequent streams which follow the regional slope
and are well adjusted to the geological structures.

16. Rectangular Pattern - In this pattern main stream and its tributaries display right
angled bands. Streams are flowing in two directions at right angle each other.
Parallel Pattern – A parallel drainage pattern consist of tributaries that flow nearly
parallel to one another.
Angulate Pattern - In this type the streams are developed equally in two directions,
but streams meet at an acute angle rather than at right angle.
Radial Pattern - This pattern develops from a central elevated tract such as volcano,
dome or doubly plunging anticlines
Inward Radial Pattern - is defined as the stream will diverge at one point or
common point by the circular network channels.
Outward Radial Pattern – Is defined as the stream will converge at common
point where the central region is depression or dome like structure is present.
Centripetal Pattern - This pattern is characterised by stream lines converging into a
central depression. Found on sinkhole, craters and other basin like depressions.

18. Annular Pattern - Such pattern may be found around maturely
dissected domes which have alternating bands of hard and soft rocks
encircling them.
Barbed Pattern - A drainage in which a stream suddenly bends back on itself
and flows in an almost reverse direction often due to glacial blocking,
suspended material river capture or local tectonic movement.
Contorted Pattern - Tributaries are parallel but hng opposite flow direction
than the main stream.
Asymmetric Pattern – The pattern of the streams has more unequally
tributaries are formed, most commonly observed in mountain region.

20. Yazoo Pattern - In hydrological or geological terms, a Yazoo stream is a
tributary stream that lies within a single floodplain with a larger river and runs
parallel to the river for a long distance and eventually joins it downstream.
Reticular Pattern – The drainage pattern exhibits network or netlike structure
of stream channels.
Phantom Pattern – It is drainage pattern of seepage ways and looks cobweb
like drainage.
Illusory Pattern – It is nearly like phantom drainage expect that this is due to
artificial drainage. soils are drained tiles is visible due to tonal contrast.

22. Complex and Compound Patterns – The group of drainage patterns dissimilar
patterns which reflect different structural controls in adjoining areas.
Deranged Pattern – this drainage knows as erratic, hap-hazard and disordered
pattern, found in the glacial region and is very irregular.
Pinnate Pattern - This pattern is characterised by long main stream and closely
spaced short tributaries. It looks like feathers.
Pectinate Pattern - Parallel gullies with pear shaped head water basins.

24. Kettle Hole Pattern – A kettle hole is formed by blocks of ice that are
separated from the main glacier - perhaps the ice front stagnated or retreated
or perhaps ice blocks were washed out from the glacier during a glacier flood.
Swallow Hole - The swallow hole has been formed as the result of chemical
weathering along a joint in the limestone bedding plane.
Thermokarst - Thermokarst is a land surface characterised by very irregular
surfaces of marshy hollows and small hummocks formed as ice-rich
permafrost thaws.
Elongate Bay Pattern – this drainage pattern is usually found in the coastal
plains and deltas and is constituted of large elliptical and parallel depressions.

26. Anastomotic pattern - The anastomotic
drainage pattern is characteristic of flood-plain
drainage.
Pincer like Pattern - Tributaries of 4th order and
3rd order show pincer like curved form. Develop
on hard igneous rocks partly fracture controlled.
Lacunate – The lakes are spaced at random and
the individual tributaries connecting them may
be dendritic drainage.

27. Significance: -
• If proper drainage is not existing in the land use area than flood can
occurring capabilities will increase.
• Water can't store easily and places where rainfall is not adequate at their
places water can't supply and canals, dam, stream, river, ponds, to ocean
water level will decreases and ground water potential also decreases.
• Most of ground water is destroyed or waste due to improper drainage in the
city and sometimes water logging occurs in monsoon and water remains
logged and pollution of water will increase, and decreases will occur, and it's
directly affects at national economical levels.

28. • The drainage pattern and their flowing nature can encourage or increase the
water storing capacity and water harvesting in the adjacent areas.
• The drainage pattern which helps to the green revolution due to the bunds
created to the drainage pattern.
• These drainage pattern help the drainage which mainly increases the ground
water potentiality.
• There are several concerns about the sustainability of irrigation and drainage
projects, and there are water quality problems related to the disposal of
drainage water.
• There have been instances where saline or high nutrient drainage water has
damaged aquatic ecosystems.

29. Conclusion

30. Thank You