Meandering River Poster Presentation by Md Wabidur Rahman, Naziat Islam, Prince Halder, Narayan Kar. Department of Geology and Mining, University of Barishal.

1. Meandering River
Naziat Islam,Prince Halder,Md.Wabidur Rahman,Narayan Kar
Department of Geology and Mining, University of Barishal
1.Introduction
A meandering river has a single channel.It always
change its channel direction by creating sinuous
winding path.It flows over gently sloping ground
and it gives a s-shape appearance.
Ichamati,Gorai,Nagar are some meandering rivers
in Bangladesh.
Figure 1: A meandering river 6.Factors control meanders
4.Geomorphic Features
*Flow velocity *Climate
*Sediment types *Slope of valley
*Bedload,Suspended load*Bed competence
8.Conclusion
9.Reference
2.Formation
5.Sinuosity
The degree of meandering of the channel of a river is measured by its
sinuosity.The sinuosity of a river is the ratio of the length of the river channel to
the straight line distance between the end points of the selected channel
reach.Tightly meandering rivers travel much further over a given length of
valley and so they have high sinuosity.A river is said to be meandering river in
the sinuosity index is above 1.5.
Figure 6:increased meandering and sinuosity of a river.
Figure 4:An ideal cross section of a point bar
Figure 3: Formation of a meandering river
Meanders are an excellent example of geological change.A meandering river
associated geomorphic features.:
Point bar Cut off
Cut bank Natural levee
Meandering scar Oxbow lake
3.Sedimentation
Meandering river channel is mainly composed of gravel bearing sandstone, sandstone and
siltstone.The sand bodies of meandering channel take dominance and gravel bodies are
minor.Meandering migrate by undercutting the bank on the outside of a bend and
depositing on a point bar on the inside of a bed.The point bar grows through lateral
accretion and is characterized by a fining upward sequence.As the flow enters a bend a
helical overturn flow develops which directs the bottom current to move up along the slope
of the point bar.This flow sorts the sediments with the finest sediments being deposited at
the top of the point bar and coarsest sediments being deposited at the bottom of the
bar.The lateral accretion surface on the point bar form large scale,low angle cross-bedding.
Figure 5:Geomorphic features
A river is a dynamic landform that can change dramatically over
time.Meandering rivers can turn into braided rivers which have numerous
channels that split and combine again.Rivers meander is essential to living
with free-flowing rivers.Water is essential to every form of life and healthy
rivers provide us with many resources.
Meandering river is formed in the middle and lower course of a river(a
gently sloping area).Its velocity is slower than the upper course.Meandering
form from straight channel with developing pools(deeper water area) and
riffles(shallow water area).Fast flowing water creats pool and slow flowing
water creats riffle.A meandering river is formed when water in the river
channel erodes the sediments of an outer bend of a riverbank and deposits
sediments on inner bends downstream.This deposition forms point bars.By
this erosional and depositional activities, a meandering river migrate and at
the end it meets with a large water body.
1.https://www.yourarticlelibrary.com/rivers/rivers-classification-stages-and-meandering/60873
2.https://g105lab.sitehost.iu.edu
3.https://www.seddepseq.co.uk
4.https://www.jstor.org
5.https://www.nps.gov
6.https://brainly.in
7.httpsn//www.ausableriver.org
Figure 2:Journey of a river
Figure 7:Gorai river catchment area
Fig 4:https://www.researchgate.net
Fig 5:https://www.shutterstock.com
Fig 6:https://www.sciencedirect.com
Fig 7:https://www.researchgate.net
Fig 1:https://www.mediastorehouse.com.au
Fig 2:https://www.riverrevise.weebly.com
Fig 3:https://www.quizlet.com
A meandering river
in Bangladesh
7.Gorai: