Fluvial Processes
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Fluvial processes encompasses the study of river channels and the sediment budgets involved in the flow of water within these channels.[1] Sediment is eroded, transported and deposited along the path of the flowing river or stream. The turbulence within the column of flowing water is a very complex system of interactions that is poorly understood. Mostly this stems from the lack of the needed empirical field measurements to perfect models of turbulence that is fundamental to the suspension of sediment in the water column.[2]
Transport and Bank Erosion
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As the potential energy of water is dissipated along the journey to the lowest possible potential within the system, sediment is picked up entrained and transported along the channel. This sediment is both picked up along the bottom of the channel and the side. When picked up along the side of the channel bank erosion occurs. Bank erosion occurs in two main ways. One is through the shear force of the river against the bank entraining particles. Another is a result of the first, as sediment is removed from a bank it can produce an overhang than will eventually fail under it's own weight.[3]
Equilibrium
editAll rivers are trying to reach an equilibrium state between the dominant discharge and sediment load by adjusting their hydraulic characteristics(width, depth,velocity,slope and roughness). Being that the earth and furthermore the universe as a whole is not static, there is never truly a permanent equilibrium the river is proceeding towards.[4]
Fluvial Landforms
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Rivers are more than just the channels they occupy. They mold the landscape surrounding them. The rivers erode and deposit sediment and carve channels through rock around them during normal flow and flood stages. Through their inherent properties they are constantly transforming the surfaces near them.[5]
Floodplain
editThe most well known landform is the floodplain. All major rivers have them, however an exact delineation is hard to define. It occupies the the low lying relatively flat areas along the river valley.[6]
References
edit- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 193-228. Wm. C. Brown Communications 1995.
- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 197. Wm. C. Brown Communications 1995.
- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 201. Wm. C. Brown Communications 1995.
- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 205. Wm. C. Brown Communications 1995.
- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 231. Wm. C. Brown Communications 1995.
- ^ Ritter, Daniel F./Kochel, Craig R./Miller, Jerry R.: "Process Geomorphology", page 231. Wm. C. Brown Communications 1995.