A misfit stream is a river that is either too large or too small to have eroded the valley or cave passage in which it flows. This term is also used for a stream or river with meanders that obviously are not proportional in size to the meanders of the valley or meander scars cut into its valley walls. If the misfit stream is too large for either its valley or meanders, it is known as an overfit stream. If the misfit stream is too small for either its valley or meanders, it is known as an underfit stream.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Dury, G. H. (1964) ''Subsurface Exploration and Chronology of Underfit Streams.'' Professional Paper no. 452-A. U.S. Geological Survey, Reston, Virginia. The term misfit stream is often incorrectly used as a synonym for an underfit stream. An underfit stream is a type of misfit stream whose discharge is too small to be correlated with either existing channel characteristics, i.e. meander radius, wavelength and channel width, or valley size

Origin

An underfit stream can result when glaciation modifies the landscape by creating glacial troughs. The rivers that occupy such valleys after the ice has retreated are not in proportion with the size of the valley. Given the scale of most glacial troughs almost all of them contain misfit streams. Misfit streams can also be caused by reductions in the

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of the stream. Channel size responds rapidly to variations in

, but valley size responds over much longer timescales. Many causes of reduced discharges are possible. If misfit streams are widespread in an area,

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, particularly a reduction in precipitation, is likely to be the cause. If a single river appears to be a misfit stream, it may be as a result of human activity through groundwater extraction or dam construction upstream. Natural causes include

stream capture Stream capture, river capture, river piracy or stream piracy is a geomorphological phenomenon occurring when a stream or river drainage system or watershed is diverted from its own bed, and flows instead down the bed of a neighbouring stream. ...

or other changes in drainage patterns. For instance, New Zealand's largest river (the Waikato) used to flow through the Hauraki Plains to the

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's east coast, but changed its course to exit on the west coast due to a large volcanic eruption, leaving its former course through the 1-km wide Hinuera Gap occupied by only a small stream.

Example

*A misfit stream named Nose Creek in

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Alberta Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...

: *A misfit river named Battle River just south of Camrose,

References

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External links

U.S. Geological Survey
further clarification of a misfit stream. Water streams