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MIXED TIDE - A type of tide in which the presence of a diurnal wave is 

 conspicuous by a large inequality in either the high- or low-water 

 heights with two high waters and two low waters usually occurring 

 each tidal day. In strictness, all tides are mixed, but the name 

 is usually applied without definite limits to the tide intermediate 

 to those predominantly semidiurnal and those predominantly diurnal. 

 (See Figure A- 10.) 



MOLE - In coastal terminology, a massive land-connected, solid-fill 



structure of earth (generally revetted), masonry, or large stone. 

 It may serve as a breakwater or pier. 



MONOCHROMATIC WAVES - A series of waves generated in a laboratory; each 

 wave has the same length and period. 



MONOLITHIC - Like a single stone or block. In coastal structures, the 

 type of construction in which the structure's component parts are 

 bound together to act as one. 



MUD - A fluid- to-plastic mixture of finely divided particles of solid 

 material and water. 



NAUTICAL MILE - The length of a minute of arc, 1/21,600 of an average 

 great circle of the earth. Generally one minute of latitude is 

 considered equal to one nautical mile. The accepted United States 

 value as of 1 July 1959 is 6,076.115 feet or 1,852 meters, approxi- 

 mately 1.15 times as long as the statute mile of 5,280 feet. Also 

 geographical mile. 



NEAP TIDE - A tide occurring near the time of quadrature of the moon with 

 the sun. The neap tidal range is usually 10 to 30 percent less than 

 the mean tidal range. 



NEARSHORE (ZONE) - In beach terminology an indefinite zone extending sea- 

 ward from the shoreline well beyond the breaker zone. It defines 

 the area of NEARSHORE CURRENTS. (See Figure A-1.) 



NEARSHORE CIRCULATION - The ocean circulation pattern composed of the 

 CURRENTS, NEARSHORE and CURRENTS, COASTAL. See CURRENT. 



NEARSHORE CURRENT SYSTEM - The current system caused primarily by wave 

 action in and near the breaker zone, and which consists of four 

 parts: The shoreward mass transport of water; longshore currents; 

 seaward return flow, including rip currents; and the longshore 

 movement of the expanding heads of rip currents. (See Figure A-7.) 

 See also NEARSHORE CIRCULATION. 



NECK - (1) The narrow band of water flowirtg seaward through the surf. 



Also RIP. (2) The narrow strip of land connecting two larger bodies 

 of land, as an isthmus. 



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