Upper Shoreface refers to the portion of the seafloor that is shallow enough to be agitated by everyday wave action, the wave base. Below that is the lower shoreface.

Process

The continuous agitation of the sea floor in the upper shoreface environment results in sediments that are winnowed of the smallest grains, leaving only those grains heavy enough that the water cannot keep them suspended.

Depth of influence

Seawater Seawater, or salt water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has appr ...

is moved in a vertical circular motion when a wave passes. The

radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...

of the circle of motion for any given water molecule decreases with depth. The maximum depth of influence of a water wave is half the

wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, tr ...

. Below that depth the water remains stationary as the wave passes. For instance, in a pool of water deep, a wave with a wavelength of would not be able to cause water movement on the bottom. However, a wave with a wavelength would be moving the water (barely) at the bottom.

References

Physical oceanography Wave mechanics {{Ocean-stub

Process

Depth of influence

See also

References