SEISMIC SEA WAVE (TSUNAMI) - A long-period wave caused by an underwater 



seismic disturbance or volcanic eruption. Commonly misnamed "tidal wave." 



SHEAR FRACTURE - An action or stress resulting from applied forces, which 

 causes or tends to cause two contiguous parts of a body to slide relatively 

 to each other in a direction parallel to their plane of contact. 



SHEET PILE - See PILE, SHEET. 



SHOAL (noun) - A detached elevation of the sea bottom, comprised of any 

 material except rock or coral, which may endanger surface navigation. 



SHOAL (verb) - (1) To become shallow gradually. (2) To cause to become 

 shallow. (3) To proceed from a greater to a lesser depth of water. 



SHORE - The narrow strip of land in immediate contact with the sea, in- 

 cluding the zone between high and low water lines. A shore of uncon- 

 solidated material is usually called a beach. 



SHORELINE - The intersection of a specified plane of water with the shore 

 or beach, (e.g., the high water shoreline would be the intersection of 

 the plane of mean high water with the shore or beach.) The line delineat- 

 ing the shoreline on National Ocean Survey nautical charts and surveys 

 approximates the mean high water line. 



SHOTCRETE - A pneumatically applied concrete or grout. 



SILT - A fine grained soil of low plasticity which may exhibit an apparent 

 cohesion due to capillary forces. See SOIL CLASSIFICATION. 



SLOPE - The degree of inclination to the horizontal. Usually expressed as 

 a ratio, such as 1:25 or 1 on 25, indicating 1 unit vertical rise in 25 

 units of horizontal distance; or in a decimal fraction (0.04); degrees 

 (2° 18»); or percent (4%). 



SLUMP - To fall or sink suddenly. 



SOIL CLASSIFICATION (size) - An arbitrary division of a continuous scale 



of grain sizes such that each scale unit or grade may serve as a convenient 



class interval for conducting the analysis or for expressing the results 

 of an analysis. 



SPALL - To breakup or reduce by chipping with a hammer; to chip or crumble. 



SPECIES - An aggregate of interbreeding populations that under natural 

 conditions is reproductively isolated. 



SPLASH ZONE - The zone immediately landward of the mean higher high water 

 level affected by the wave spray. - 



STONE, DERRICK - Stone heavy enough to require handling individual pieces 

 by mechanical means, generally 1 ton and up. 



STRENGTH - Load capacity at failure. Depending on the usage, load may be 

 expressed in stress, force per unit width, or force. 



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