`DEE `ALEX `ZHIHAN `JOSHUA `JUEHAO
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21) Alex Low Shaw Boon

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27) Kwan Zhong-Hao Joshua

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River Flows In You

July 2009
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Monday, July 13, 2009 at 12:55 AM
Geography Project: The Process

This is a video showing the process of constructing the model for the natural river landforms. We have decided on three river landforms : waterfall, meander and oxbow lake.


We will first show how we obtained the materials and put them to use.





The base for our model is constructed.





We have started placing plasticine on the base of the model.




The model is almost done.




In the model, we have clearly shown that the waterfall was formed as a result of the movement of the Earth's crust. The waterfall was actually a river, and when the Earth's crust slides along a fault line, part of the river bed is displaced resulting in a waterfall. As seen in the model, the sides are painted different colours to distinguish the different rock layers of different resistance.

In our model, the waterfall immediately flows into a meander. We cannot afford to have a long middle course due to space constraint, hence the middle course is very short.


Meanders are usually found in the middle or lower course, or where the floor of the valley is broad and the gradient is gentle. Erosion occurs on the outer bank of the meander, and the eroded sediments are transported to the inner bank where they are deposited.


Oxbow Lake

  • lateral erosion & undercutting occur on concave banks where the stream flows the fastest. Deposition on convex bank due to water of slow speed.

  • continuous erosion on concave bank & deposition on convex bank cause the formation of very pronounced meander with two neighbouring concave banks getting closer


  • two concave banks move closer to each other, forming a loop

  • loop becomes more distinct, and is then separated by the narrow neck of land

  • neck gets narrower with continual erosion & deposition

  • two banks eventually meet

  • sediments deposited dam up water in the cut-off, forming an oxbow lake

  • river flows in a straight path for a shorter distance, before meandering again

  • cut off from main river, oxbow lakes will eventually dry up due to evaporation, encouraging vegetation growth

NOTE! : Oxbow lake may not be permanent as water may dry up and be filled with sediment & vegetation growth.