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The Hjulström curve, named after Filip Hjulström (1902–1982), is a graph used by hydrologists and geologists to determine whether a river will erode, transport, or deposit sediment. It was originally published in his doctoral thesis "Studies of the morphological activity of rivers as illustrated by the river Fyris. [1]" in 1935. The graph ...
Meandering rivers, which form a sinuous path in a usually low-gradient plain toward the end of a fluvial system. Anastomosed river is a rare case of a relatively straight, complicated vertical sequence of river deposits with banks held together by dense vegetation.
The model in its original form is intended to explain relief development in temperate landscapes in which erosion by running water is assumed to be of prime importance. [5] [7] Nevertheless, the cycle of erosion has been extended, with modifications, into arid, semi-arid, savanah, selva, glacial, coastal, karst and periglacial areas.
The terms river morphology and its synonym stream morphology are used to describe the shapes of river channels and how they change in shape and direction over time. The morphology of a river channel is a function of a number of processes and environmental conditions, including the composition and erodibility of the bed and banks (e.g., sand, clay, bedrock); erosion comes from the power and ...
In geomorphology fluvio-thermal erosion is the combined mechanical and thermal erosion of an unfrozen river or stream against ice-rich soils and sediments.The erosional process includes the thawing of ice sediments by a strong water flow and once the surface is unfrozen, mechanical erosion occurs only if hydraulic forces are powerful enough to incise the riverbank material. [1]
The amount of matter carried by a large river is enormous. It has been estimated that the Mississippi River annually carries 406 million tons of sediment to the sea, [5] the Yellow River 796 million tons, and the Po River in Italy 67 million tons. [6] The names of many rivers derive from the color that the transported matter gives the water.
There are two primary mechanisms of stream bank erosion: fluvial erosion and mass failure. Fluvial erosion is the direct removal of soil particles by flowing water. The rate of fluvial erosion is determined both by the force of the flowing water (e.g. faster flow equals more force) and the resistance of the bank material to erosion (e.g. clay is generally more resistant to erosion than sand).
In geomorphology a river is said to be rejuvenated when it is eroding the landscape in response to a lowering of its base level. The process is often a result of a sudden fall in sea level or the rise of land. The disturbance enables a rise in the river's gravitational potential energy change per unit distance, increasing its riverbed erosion rate.