By definition, a lake is a small body of water that occupies a depressed land surface. These depressions of land are called “catch basin”. If enough water flows on the basin, it gradually forms an inland lake.
Lakes are formed due to the constant or gradual flow of water in low lying areas. This water comes largely to natural causes such as rainfalls or the melting of snow. The waters that were collected in the catch basin may be coming from streams, rivers, underground springs as well as ground waters.
But how does these catch basin formed? There are several ways towhich these basins are formed. One most common is the result of a fault or warping of the earth’s inner layer (the crust in particular). One famous example of this lake formation is the Lake Superior in North America.
Lakes can also be formed after a volcanic eruption. When a volcano erupts, its lave flow can block an outlet of a valley in which it creates a permanent catch basin. And sometimes, the crater of the volcano creates a great depression to which water is collected over time turning the entire crater into a huge lake. One example of a lake that was formed by a volcano is the Crater Lake that is located in southern Oregon.
Glacial erosion can also create lake formations. As the glacier erodes, huge quantities of water will settle down to thelowest depression of land. Lake Winnipeg on Canada is one example of a lake that was formed in this manner.
Lakes can be also formed through the movement of the sea waves. Waves and shore currents can sometimes block and close inlets of water which in turn creates temporary lakes in rivers above the land. The blocked river water builds its own flood plains and deposits silts in the process. Over time, the flooded plain becomes large enough to form a lake.
In area where great limestone makes up most of its underground land mass can also form lakes. Ground water may dissolve and erode enough quantities of limestone which resulted to huge sinkholes to which water is collected and forms a catch basin. The state of Florida in the United States has many of these likes formed in this manner.
And lastly, lakes can also be formed artificially by man. This is when river dams are build to collect water for human use. The most famous of this is the Lake Mead which was artificially formed when the Hoover Dam was built in the Colorado River.