The deepest place of a riverbed or other reservoir, drilled by a whirlpool or stream, is popularly called the pool. What is a depression in the bottom relief?
Types of whirlpool
The rotating thickness of the water can be observed in a variety of reservoirs - in small rivers and in the open ocean. It is formed during the sudden expansion of the channel, when currents of different temperatures and speeds collide. Water, rotating in a small space, rushes to the outer edge of the cycle, forming a recess in the center. At sea, whirlpools occur in the collision of oncoming currents, tidal and ebb waves. Water in them can move with great speed. In the open ocean, the size of the formed funnel can reach several kilometers.
On a river, the speed of rotation of water is usually equal to the speed of its main stream. Water-holes are typical enough for mountain rivers. They can form deep holes called suvodis. Here, the rotation of water occurs in one direction behind the pier, cape or other ledge. The stream usually moves from bottom to top along the axis of rotation of the whirlpool. Usually, a whirlpool is found below the dam at concave shores on steep bends. What is a natural phenomenon? This is a kind of whirlpool, in which the flow goes down along the axis of the water cycle.
Pool
The nature of their formation is due to the fact that the flow velocity throughout the river flow is rarely constant. It accelerates, slows down, sometimes almost disappears. The reverse course also occurs. In a section of the river, called rapid river, it becomes very turbulent and fast. The reason for this phenomenon is often narrowing the coast, steep slopes. The rapid flow is accompanied by a kind of "boiling" of water on the rapids. Such whirlpools wash the hole in the bottom, forming a pool. Everyone knows that such a place is dangerous. No wonder the very word "whirlpool" is associated primarily with words fraught with danger: "bottomless", "deep", "dark."
Quiet water, but the whirlpools are deep
A person in a difficult situation or trouble is often compared to a person in a pool. What is the recess in the topography of the bottom of the reservoir is better to bypass, even our ancestors knew. According to their beliefs, such a whirlpool often ruined everything in its path, pulling small craft and ships into its pharynx. Ancient sayings about whirlpools have always been used as a warning about possible troubles. These are precisely the places where all evil should be found. They stayed away from such whirlpools, since it is not always possible to predict where a funnel is located under water that can tighten to the bottom. Many people were drowning in the whirlpools, as they said earlier - the devils were dragged to the bottom.
Whirlpools may not be very dangerous, but they should not be underestimated. In calm water, the pits they form can be quite deep. At rifts and elders, quiet pools are often found. At rifts where it is shallow, the current is rapid and rapid, and over the whirlpool it is usually slow. The proverb says "still water, but whirlpools are deep."