SEA BED 



Theoretically, in light scattering-, there is no loss 

 of intensity, but only a redirection of light. 



3. Change of direction of a subatomic particle 

 or photon as a result of a collision or interaction. 

 (70) 



scattering coefficient — (or total scattering coef- 

 -ficient). A measure of the attenuation due to 

 scattering of radiation as it traverses a medium 

 containing scattering particles. (5) 



scattering function — The intensity of scattered 

 radiation in a given direction per lumen of flux 

 incident upon the scattering material. 



Wlien the collection of scattering particles is 

 taken to be those in one unit volume, the associ- 

 ated scattering function is known as the volume 

 scattering function. (5) 



scattering loss — That part of the transmission 

 loss which is due either to scattering wuthin the 

 medium or due to roughness of the reflecting 

 surface. (6) 



schistosome dermatitis — (or sioimmer's itch^ sea- 

 hather's enoption). An irritating skin condi- 

 tion incurred by bathers in both fresh and salt 

 waters and characterized by the eruption of red- 

 dish wheals and a severe itching sensation. The 

 cercarian larvae of certain parasitic trematode 

 worms produce the dermatitis when they enter 

 the skin and die. 



schizopod stage — That stage in the development 

 of a decapod crustacean when it resembles an 

 adult. (26) 



school — A large number of one kind of fish or 

 other aquatic animals swimming or feeding 

 together (a school of herring) . See shoal. 



scintillation — 1. A flash of light produced in a 

 phosphor by an ionizing agent. (41) 



2. A generic term for rapid variations in ap- 

 parent position, brightness, or color of a distant 

 luminous object viewed through the atmosphere. 

 (5) 



scintillation counter — The combination of phos- 

 phor, photomultiplier tube, and associated cir- 

 cuits for counting light emissions produced in 

 the phosphors. (70) {See figure for photo- 

 multiplier tube.) 



scintillation spectrometer — A scintillation 

 counter adapted to the study of energy distrib^^- 

 tions. (41) 



scintillator — (or 'plws'plior) . A transparent ma- 

 terial, either crystalline, organic, or liquid, which 

 produces a flash of light as a result of fluorescent 

 radiation emitted by atoms of the material when 

 they return to their normal energy state after 

 having been ionized or excited by charged parti- 

 cles passing through the material. (18) 



scoopiish bottom sampler — A small bottom sedi- 

 ment sampling device for underway use which 

 consists essentially of a streamlined weighted 

 tube with stabilizing fins. The leading end of 

 the tube is completely open so that a scooping 

 effect is achieved when the sampler is towed. 



Bottom conttuit releases a spring activated cover 

 over the tube's open end so that any sediment 

 sampled can be brought to the surface. 



scoria — Volcanic rock fragments usually of basic 

 composition, characterized by marked vesicular- 

 ity, dark color, high density, and a partly crys- 

 talline texture. Fragments between 4 and 32 

 millimeters are equivalent to volcanic cinders. 



scour — The downward and sideward erosion of 

 a sediment bed by wave or current action. 



scree — See talus. 



screw ice — 1. See pressure ice. 



2. Small ice fragments in heaps or ridges pro- 

 duced by the crushing together of ice cakes. 

 Also applied to small formations of ridged ice, 

 rafted ice, and hummocked ice. (59) 



screwing pack — An ice pack in which the ice 

 floes or ice cakes are in rotary motion due to the 

 influence of wind and current. (68) 



scyphozoan — One of a class (Scyphozoa or Scy- 

 phomedusae) of coelenterates in which the 

 polyp or hydroid stage is minimized or insigni- 

 ficant and the medusoid stage is well developed. 

 The true jellyfishes belong to this group. 



sea — 1. See ocean. (5) 



2. A subdivision of an ocean. 



All seas except inland seas are physically 

 interconnected parts of the earth's total salt 

 water system. Two types are distinguished, 

 mediterranean and adjacent. Mediterraneans 

 are groups of seas, collectively separated fi'om 

 the major water body as an individual sea. 

 Adjacent seas are those connected individually 

 to the larger body. (5) 



3. See sea state. 



4. Waves generated or sustained by winds 

 within their fetch ; opposed to swell. See fully 

 developed sea. 



sea anemone — Any of numerous anthozoans 

 (Actiniaria) whose form, bright colors, and ten- 

 tacles about the mouth often give them a super- 

 ficial resemblance to a flower. 



sea arch — (or marine arch^ natural arch, marine 

 hridge). Wave erosion of a cave or tumiel 

 through a headland leaving a bridge of rock 

 over the water. 



sea arrow — ^(or flying squid). One of a family 

 (Ommastrephidae), but more particularly one 

 of a genus (Ommastrephes) of this family of 

 cephalopods which are elongated and stream- 

 lined and possess terminal fins which unite in a 

 point at the tei-minus of the bodj-. These species 

 are capable of rapid swimming and can overtake 

 schools of fish on which they prey; they often 

 hurtle out of the water and sail through the air, 

 at times landing on the decks of ships. 



sea bar — See belt. 



seabather's eruption — See schistosome derma- 

 titis. 



seabeach — See beach. 



sea bed — See sea floor. 



141 



