upper shoreface
{{Short description|Portion of the seafloor that is shallow enough to be agitated by everyday wave action}}
{{For|the lower portion of the seafloor|Lower shoreface}}
File:CB UpShoreface.jpg upper shoreface sandstones]]
Image:wavebase.jpg diagram.]]
Upper shoreface refers to the portion of the seafloor that is shallow enough to be agitated by everyday wave action, the wave base.{{cite book | title=Water wave mechanics for engineers and scientists | author=R. G. Dean and R. A. Dalrymple | year=1991 | series=Advanced Series on Ocean Engineering | volume=2 | publisher=World Scientific, Singapore | isbn=978-981-02-0420-4 }}
Process
= Depth of influence =
Seawater is moved in a vertical circular motion when a wave passes. The radius 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. Below that depth the water remains stationary as the wave passes.
For instance, in a pool of water {{convert|1|ft|m}} deep, a wave with a wavelength of {{convert|1|ft|m}} would not be able to cause water movement on the bottom. However, a wave with a {{convert|2|ft|m}} wavelength would be moving the water (barely) at the bottom.