Earth science Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres ...

, a pothole is a smooth, bowl-shaped or cylindrical hollow, generally deeper than wide, found carved into the rocky bed of a watercourse. Other names used for riverine potholes are pot, (stream) kettle,

giant's kettle A giant's kettle, also known as either a giant's cauldron, moulin pothole, or glacial pothole, is a typically large and cylindrical Pothole (landform), pothole drilling, drilled in solid rock (geology), rock underlying a glacier either by water ...

, evorsion, hollow, rock mill, churn hole, eddy mill, and kolk.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds., 2011. ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 800 pp. Although somewhat related to a pothole in origin, a

plunge pool A plunge pool (or plunge basin or waterfall lake) is a deep depression in a stream bed at the base of a waterfall or Shut-in (river), shut-in. It is created by the erosion, erosional forces of cascading water on the rocks at the formation's bas ...

(or plunge basin or waterfall lake) is the deep depression in a

stream bed A streambed or stream bed is the bottom of a stream or river and is confined within a Stream channel, channel or the Bank (geography), banks of the waterway. Usually, the bed does not contain terrestrial (land) vegetation and instead supports d ...

at the base of a

waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in seve ...

. It is created by the

erosion Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, tran ...

al forces of

turbulence In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to laminar flow, which occurs when a fluid flows in parallel layers with no disruption between ...

generated by water falling on rocks at a waterfall's base where the water impacts.Marshak, Stephen, 2009. ''Essentials of Geology,'' W. W. Norton & Company, 3rd ed. Potholes are also sometimes referred to as swirlholes. This word was created to avoid confusion with an English term for a vertical or steeply inclined

karst Karst () is a topography formed from the dissolution of soluble carbonate rocks such as limestone and Dolomite (rock), dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. Ther ...

ic shaft in

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

. However, given widespread usage of this term for a type of fluvial sculpted bedrock landform, ''pothole'' is preferred in usage to ''swirlhole''.Richardson, K. and Carling, P., 2005. ''A typology of sculpted forms in open bedrock channels.'' ''Special Paper'' 392. Boulder, Colorado: Geological Society of America. 108 pp. ThePotThatWashesItself

The term ''pothole'' is also used to refer to other types of depressions and basins that differ in origin. For example, some authorsChan, M.A., Moser, K., Davis, J.M., Southam, G., Hughes, K. and Graham, T., 2005. ''Desert potholes: ephemeral aquatic microsystems.'' ''Aquatic Geochemistry'', 11(3), pp. 279-302.Hughes, Kebbi A., 2012
''Bacterial Communities and their Influence on the Formation and Development of Potholes in Sandstone Surfaces of the Semi-Arid Colorado Plateau''
University of Western Ontario - Electronic Thesis and Dissertation Repository. Paper 543. refer to '' panholes'' found in the

Colorado Plateau The Colorado Plateau is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the Southwestern United States. This plateau covers an area of 336,700 km2 (130,000 mi2) within w ...

also as ''potholes''. Other terms used for panholes are ''gnamma'' (Australia), ''opferkessel'' (German, roughly “sacrificial basin”), ''armchair hollows'', ''weathering pans'' (or ''pits'') and ''solution pans'' or ''solution pits''.Twidale, C.R., and Bourne, J.A., 2018
''Rock basins (gnammas) revisited.''
Géomorphologie: Relief, Processus, Environnement, Articles sous presse, Varia, mis en ligne le 08 janvier 2018, consulté le 01 juillet 2018. In another case, the term ''pothole'' is used to refer to a shallow depression, generally less than in area that occurs between

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

s or on subdued morainic relief on a

prairie Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the ...

, as in

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

and

the Dakotas The Dakotas, also known as simply Dakota, is a collective term for the U.S. states of North Dakota and South Dakota. It has been used historically to describe the Dakota Territory, and is still used for the collective heritage, culture, geo ...

, and often contains an intermittent pond or marsh that serves as a nesting place for

waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...

Origin

The consensus of geomorphologists and sedimentologists is that fluvial potholes are created by the grinding action of either a stone or stones or coarse

sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

(

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

gravel Gravel () is a loose aggregation of rock fragments. Gravel occurs naturally on Earth as a result of sedimentation, sedimentary and erosion, erosive geological processes; it is also produced in large quantities commercially as crushed stone. Gr ...

pebble A pebble is a clastic rocks, clast of rock (geology), rock with a grain size, particle size of based on the Particle size (grain size), Udden-Wentworth scale of sedimentology. Pebbles are generally considered larger than Granule (geology), gra ...

boulder In geology, a boulder (or rarely bowlder) is a rock fragment with size greater than in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In ...

s), whirled around and kept in motion by eddies within and force of the stream current in a given spot. Being a spectacular feature of bedrock river channels, they have been and still are studied extensively and considered as a key factor in bedrock channel development and morphology and important factor in the incision of bedrock channels.Das, B.C., 2018. ''Development of Streambed Potholes and the Role of Grinding Stones.'' ''Journal of Environmental Geography.'' 11 (1–2), 9–16.Whipple, K.X., Hancock, G.S., and Anderson, R.S., 2000. ''River Incision Into Bedrock: Mechanics And Relative Efficacy Of Plucking, Abrasion And Cavitation.'' ''Geological Society Of America Bulletin.'' 112, 490–503.

References

{{reflist Landforms Depressions (geology)