SEABED PROPERTY MEASUREMENT - Determination of seabed soil properties, 

 such a^ bearing capacity, consolidation, specific gravity, or 

 chemical composition, by measuring other properties, such as resist- 

 ance to impact, sound transmission, electrical resistance, or 

 radioactivity. 



SEABED SCOUR PROTECTION - Prevention of the removal of underwater mate- 

 rial at the base or toe of a coastal structure by waves and currents. 



SEABED SITE SURVEY - A method of making a detailed survey of a small 

 area, such as a construction site. 



SEABED SOIL TREATMENT - Chemical or mechanical treatment of soil in the 



seabed to improve its qualities as construction or foundation material. 



SEABED TRENCHER - A remote-controlled submersible excavator for forming 

 trenches in the seabed, including towed units for burying pipeline. 



SEABED WATER, PROCESS STRUCTURE - A structure fixed to the seabed for 

 transporting or storing water, including cooling water intakes, 

 sewer outfalls, or sewage storage tanks. 



SEAWALL - A structure separating land and water areas, primarily designed 

 to prevent erosion and other damage due to wave action. 



SEDIMENTATION MEASUREMENT - Determination of sediment movement or accumu- 

 lation, including tracer studies or the measurement of thin bottom 

 layers . 



SEISMIC ACOUSTIC TRANSMITTER ARRAY - A grouping of underwater seismic 

 impulse sources, sometimes mounted in a three-dimensional framework. 



SEISMIC EXPLOSIVE ACOUSTIC TRANSMITTER - An underwater seismic impulse 

 source using a sudden discharge of pressure generated by igniting 

 dynamite or a gas mixture, emitting a gas bubble, or producing an 

 * electric arc. 



SEISMIC HYDRAULIC ACOUSTIC TRANSMITTER - An underwater seismic impulse 

 source using the compression and flow properties of water to produce 

 signal-generating water-hammer or turbulence effects. 



SEISMIC HYDROPHONE - A single receiving unit for underwater seismic use. 



SEISMIC HYDROPHONE ARRAY - A grouping of underwater seismic receivers, 

 including one-dimensional arrangements within a streamer cable or 

 three-dimensional arrangements of streamer cables or of hydrophones in 

 a framework. 



SEISMIC IMPLOSIVE ACOUSTIC TRANSMITTER - An underwater seismic impulse 

 source using the sudden retraction of a piston or the collapse of a 

 bubble of steam for implosion generation. 



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