EM 1110-2-1100 (Change 1)
31 Jul 03
(1) Commonly, water of such a depth that surface waves are noticeably affected by bottom topography. It is
customary to consider water of depths less than one-half the surface wavelength as shallow water. See TRANSITIONAL
ZONE and DEEP WATER. (2) More strictly, in hydrodynamics with regard to progressive gravity waves, water in which the
SHALLOW WATER WAVE
A PROGRESSIVE WAVE which is in water less than 1/25 the wave length in depth.
Instabilities of the surf zone longshore current commonly found on beaches with barred depth profiles. These
instabilities are vertical motions with little surface elevation expression. Conservation of vorticity is the restoring
See SHEAR INSTABILITIES
The removal of a thin layer of surface material, usually topsoil, by a flowing sheet of water.
Sediment grains under high sheer stress moving as a layer that extends from the bed surface to some distance below
(on the order of a few cm). Grains are transported in the direction of fluid flow.
See PILE, SHEET.
A sheet on which field control and hydrographic data such as soundings, depth curves, and regions surveyed with a
wire drag are plotted before the production of a final chart.
See CONTINENTAL SHELF.
See INSULAR SHELF.
(1) Loosely and commonly, any beach material coarser than ordinary gravel, especially any having flat or flattish
pebbles. (2) Strictly and accurately, beach material of smooth, well-rounded pebbles that are roughly the same size. The
spaces between pebbles are not filled with finer materials. Shingle often gives out a musical sound when stepped on. The
term is more widely used in Great Britain than in the United States.
(1) (noun) A detached area of any material except rock or coral. The depths over it are a danger to surface
navigation. Similar continental or insular shelf features of greater depths are usually termed BANKS. (2) (verb) To become
shallow gradually. (3) To cause to become shallow. (4) To proceed from a greater to a lesser depth of water.
Decrease in water depth. The transformation of wave profile as they propagate inshore.
Appendix A Glossary of Coastal Terminology