GENERAL GEOLOGY

Detailed explanation-1: -The lowest elevation that a river channel can erode is referred to as ultimate base level. For rivers that empty into an ocean, ultimate base level is equal to sea level. At this elevation, the gradient (slope) of the river is equal to zero.

Detailed explanation-2: -Base level is the lowest level to which a stream can erode. It is ultimately controlled by sea level. A drop in base level causes the stream to erode lower to a new level.

Detailed explanation-3: -baselevel, in hydrology and geomorphology, limit below which a stream cannot erode. Upon entering a still body of water, a stream’s velocity is checked and thus it loses its eroding power; hence, the approximate level of the surface of the still water body is the stream’s baselevel.

Detailed explanation-4: -The lowest level of a river is called the base level, this is normally found at sea level. The study of river long profiles shows that they have a concave shape, with a steeper upper section and a gentle lower section.

Detailed explanation-5: -Sea level is the base level for measuring elevation and depth on Earth. Because the ocean is one continuous body of water, its surface tends to seek the same level throughout the world. However, winds, currents, river discharges, and variations in gravity and temperature prevent the sea surface from being truly level.