Lake

A lake is an area filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes can be contrasted with rivers or streams, which are usually flowing.

A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river.

Lakes lie on land and are not part of the ocean, and therefore are distinct from lagoons, and are also larger and deeper than ponds, though there are no official or scientific definitions.

A pond is a body of standing water, either natural or artificial, that is usually smaller than a lake.

The majority of lakes on Earth are freshwater, and most lie in the Northern Hemisphere at higher latitudes.

Fresh water includes water in ice sheets, ice caps, glaciers, icebergs, bogs, ponds, lakes, rivers, streams, and even underground water called groundwater.

Some of the well-known and largest lakes on Earth are rift lakes occupying rift valleys, e.g. Central African Rift lakes and Lake Baikal.

A rift lake is a lake formed as a result of subsidence related to movement on faults within a rift zone, an area of extensional tectonics in the continental crust.

Canada, with a deranged drainage system has an estimated 31,752 lakes larger than 3 km² and an unknown total number of lakes, but is estimated to be at least 2 million.

In geomorphology, drainage systems, also known as river systems, are the patterns formed by the streams, rivers, and lakes in a particular drainage basin.

Crater lakes are formed in volcanic craters and calderas, which fill up with precipitation more rapidly than they empty via either evaporation, groundwater discharge, or combination of both.

A crater lake is a lake that forms in a volcanic crater or caldera, such as a maar; less commonly and with lower association to the term a lake may form in an impact crater caused by a meteorite, or in the crater left by an artificial explosion caused by humans.

Other well-known tectonic lakes, Caspian Sea, the Sea of Aral, and other lakes from the Pontocaspian occupy basins that have been separated from the sea by the tectonic uplift of the sea floor above sea level.

The Caspian Sea is the largest inland body of water in the world and accounts for 40 to 44% of the total lacustrine waters of the world.

A lake is an area filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake.

Sink: an endorheic depression generally containing a persistent or intermittent (seasonal) lake, a salt flat (playa) or dry lake, or an ephemeral lake.

Glacial lakes include proglacial lakes, subglacial lakes, finger lakes, and epishelf lakes.

A subglacial lake is a lake under a glacier, typically an ice cap or ice sheet.

Lakes lie on land and are not part of the ocean, and therefore are distinct from lagoons, and are also larger and deeper than ponds, though there are no official or scientific definitions.

In Latin America, the term laguna in Spanish, which lagoon translates to, may be used for a small fresh water lake in a similar way a creek is considered a small river.

Smaller solution lakes that consist of a body of standing water in a closed depression within a karst region are known as karst ponds. Limestone caves often contain pools of standing water, which are known as underground lakes. Classic examples of solution lakes are abundant in the karst regions at the Dalmatian coast of Croatia and within large parts of Florida.

Lake Okeechobee is the largest freshwater lake in the U.S. state of Florida.

An example of a landslide lake is Quake Lake, which formed as a result of the 1959 Hebgen Lake earthquake.

Quake Lake (officially Earthquake Lake) is a lake in southwestern Montana in the United States.

F.A. Forel, who is also referred to as the father of limnology, was the first scientist to classify lakes according to their thermal stratification.

Lake stratification is the separation of lakes into three layers:

Based upon thermal stratification, lakes are classified as either holomictic lakes or meromictic lakes.

In ordinary, "holomictic" lakes, at least once each year, there is a physical mixing of the surface and the deep waters.

Lakes can be contrasted with rivers or streams, which are usually flowing.

Mouth: The point at which the stream discharges, possibly via an estuary or delta, into a static body of water such as a lake or ocean.

They form where there is no natural outlet, a high evaporation rate and the drainage surface of the water table has a higher-than-normal salt content.

Springs, rivers, lakes and oases occur when the water table reaches the surface.

Vlei is a name used in South Africa for a shallow lake which varies considerably in level with the seasons.

A vlei is a shallow minor lake, mostly of a seasonal or intermittent nature.

Landslide lakes are lakes created by the blockage of a valley by either mudflows, rockslides, or screes.

The water impounded by a landslide dam may create a dam reservoir (lake) that may last from short times to several thousand years.

The most common type of fluvial lake is a crescent-shaped lake called an oxbow lake due to the distinctive curved shape.

When a river reaches a low-lying plain, often in its final course to the sea or a lake, it meanders widely.

Based upon thermal stratification, lakes are classified as either holomictic lakes or meromictic lakes.

Holomictic lakes are lakes that have a uniform temperature and density from top to bottom at a specific time during the year, which allows the lake waters to completely mix.

If such a lake consists of a large area of standing water that occupies an extensive closed depression in limestone, it is also called a karst lake.

Their shallow lakebed is usually an insoluble layer of sediment so that water is impounded, leading to the formation of lakes.

Not only does this promote the creation of lakes by the disruption of preexisting drainage networks, it also creates within arid regions endorheic basins that containing salt lakes (also called saline lakes).

A salt lake or saline lake is a landlocked body of water that has a concentration of salts (typically sodium chloride) and other dissolved minerals significantly higher than most lakes (often defined as at least three grams of salt per litre).

A shrunken lake is a lake which has drastically decreased in size over geological time. Lake Agassiz, which once covered much of central North America, is a good example of a shrunken lake. Two notable remnants of this lake are Lake Winnipeg and Lake Winnipegosis.

Lake Winnipeg (Lac Winnipeg) is a very large, but relatively shallow 24514 km2 lake in North America, in the province of Manitoba, Canada.

A shrunken lake is a lake which has drastically decreased in size over geological time. Lake Agassiz, which once covered much of central North America, is a good example of a shrunken lake. Two notable remnants of this lake are Lake Winnipeg and Lake Winnipegosis.

A shrunken lake is a still extant natural lake that has permanently shrunk considerably in size over time, possibly to the point where it has divided into two or more smaller lakes.

Lakes have numerous features in addition to lake type, such as drainage basin (also known as catchment area), inflow and outflow, nutrient content, dissolved oxygen, pollutants, pH, and sedimentation.

Water bodies include for example lakes, rivers, oceans, aquifers and groundwater.