Lakes are the natural reservoirs which are formed as a result of filling with water of deepenings of sushi. The reasons of formation of these deepenings and ways of filling with their water can be various therefore there are several types of lakes.
Instruction
1. The most part of large lakes on our planet appeared as a result of tectonic processes in earth crust. As a result of the movement of plates and earthquakes, cracks in earth crust and its deflections are formed. In these deepenings water also accumulates. For example, Lake Onega is located in a deflection, and Lake Baikal in a huge tectonic crack.
2. Volcanic lakes are usually formed in craters of extinct volcanoes. There is a lot of such lakes in regions with high volcanic activity - on Kamchatka, in Japan. Also volcanic call lakes which are formed in places where the stiffened lava which is cast out from a volcano partitions off the bed of the river.
3. In northern regions of the earth there are a lot of glacial lakes. Their hollows were formed as a result of the movement of glaciers which pressed through the top soft layer of the earth and left after the leaving decrease in a relief. In mountains of the lake also arise thanks to glaciers which, thawing, leave behind a moraine - mix of sand, stones, the earth. It can block the mountain river therefore the lake is formed. Mountain lakes are also formed as a result of collapses when stones partition off the bed of the river.
4. In those areas where bark is put from plasters, dolomite and limestones, water can wash away breed, as a result empty spaces - karst caves which can be filled with water underground are formed. So there is a most part of underground lakes.
5. In permafrost regions, soil can sink at summer thawing therefore small lakes are formed.
6. Some lakes are formed near the sea coast when the sand braid separates the shallow site from the sea, call such lakes lagoons. If the tongue of sand separates the section of the river, the lake is also formed, but it is called the estuary.
7. Sometimes the bed of the river is too bent, but gradually there is its rectification, and the curvilinear site remains away from the course, that is there is a lake called Staritsa.