MARINE BIOGEOGRAPHY 



marine biogeography— The description of the dis- 

 tribution of mai'ine animals and plants, and 

 analyses of those factors which determine the 

 distribution and abundance of a eiven species. 

 (25) ^ 



marine biology— The study of the plants and ani- 

 mals living in the sea. See biological oceanog- 

 raphy. 



marine borer — Any marine invertebrate that ex- 

 cavates tunnels, holes, or depressions in one or 

 more of a variety of materials by abrasive, chew- 

 ing, or chemical action. Marine borers exist in 

 several phyla, including the sponges, annelids, 

 arthropods, mollusks, and echinoderms. The 

 most destructive of the borers on a worldwide 

 basis are the shipworms, crustacean borers, 

 and rock borers. 



marine bridge — See sea arch. 



marine-built terrace— A terrace seaward of a 

 marine-cut terrace, shore platform, or plain of 

 marine abrasion which consists of materials 

 eroded from the marine-cut terrace. (2) 



marine cave — See sea cave. 



marine cliff — A cliff or slope marking the inshore 

 limit of beach erosion. It may vary from an in- 

 conspicuous slope to an escarpment hundreds 

 of feet high. (68) 



marine climate — (also called manthne climate, 

 oceanic climate). A regional climate which is 

 imder the predominant influence of the sea, that 

 is, a climate characterized by oceanicity; the 

 antithesis of a continental climate. 



Such a climate is found where the prevailing 

 winds blow onshore as on oceanic islands and 

 on the western coasts of the continents in middle 

 latitudes. It extends inland either until it meets 

 a climatic divide or, in level country, until it 

 becomes modified and gradually attains greater 

 continentality. A marine climate is character- 

 ized by small diurnal and annual ranges of tem- 

 perature, with retardation of the annual ex- 

 tremes until one or two months after each 

 solstice. (5) 



marine-cut terrace— (or wave-cut terrace). The 

 level or gently sloping submerged shelf formed 

 along a sea coast by the erosive action of waves 

 and currents. 



marine ecology — The science which embraces all 

 aspects of the interrelations of marine organisms 

 and their en^'ironment and the interrelations be- 

 tween the organisms themselves. (38) 



marine environments — See classification of 

 marine environments. 



marine geology — See geological oceanography. 



marine meteorology— That part of meteorology 

 which deals mainly with oceanic areas, includ- 

 ing island and coastal regions. In particular 

 it serves the practical needs of surface and air 

 navigation over the oceans. 



Since there is a close interaction between 

 ocean and atmosphere, and oceanic influences 

 upon weather and climate can be traced far 



inland over the continents, modern meteorology 

 uses this name mainly for making regional or 

 administrative distinctions. (5) 



marine salina — A body of salt water separated 

 from the sea by a sand or gravel barrier through 

 which sea water percolates. Marine Salinas are 

 found along arid coasts where little or no inflow 

 of fresh water occurs. (2) 



marine snow — See sea snow. 



manning — The submergence of low-lying kind by 

 an epicontinental sea. (2) 



maritime air — A type of air whose characteris- 

 tics are developed over an extensive water sur- 

 face and which, therefore, has the basic maritime 

 quality of high moisture content in at least its 

 lower levels. (6) 



maritime climate — See marine climate. 



marl — A calcareous clay, or a mixture of clay and 

 particles of calcite or dolomite and shell frag- 

 ments. Often applied to calcareous sediments 

 ranging in size from clay through sand. See 

 tosca. 



marl ball — See algal biscuits. 



marlite — See marlstone. 



marlstone — (or marlite). An indurated mixture 

 of calcium carbonate and clay of which clay 

 comprises 25 to 75 percent. (2) 



Marsden chart — A system introduced by Marsden 

 early in tlie nineteenth century for showing the 

 distribution of meteorological data on a chart 

 especially over the oceans. A Mercator map 

 projection is used; the world between 90°N and 

 80° S being divided into Marsden "squares" each 

 of 10 degrees latitude by 10 degrees longitude. 

 These squares are systematically numbered to 

 indicate position. Each square may be divided 

 into quarter squares, or into 100 one-degree sub- 

 squares numbered from 00 to 99 to give the posi- 

 tion to the nearest degree. (5) 



marsh — An area of soft wet land. Flat land 

 periodically flooded by salt water is called a salt 

 marsli. Sometimes called slough. (68) 



marsh bar — A narrow ridge of sand at the edge 

 of a marsh undergoing wave attack. 



mascaret — f^ee bore. 



mass movement — I^nit movement or slippage of 

 a mass of sediment down a slope, such as in a 

 submarine canyon, wliich often initiates a tur- 

 bidity current. 



mass transport — The transfer of water from one 

 region to another originating from the orbital 

 motion of waves, (''^ee figure for nearshore 

 current system.) 



mass transport speed — The speed of the current 

 originating from waves. 



matrix — Eock or sediment in which larger grains 

 are imbedded in a mass of smaller grains. 



mature wave platform — A platform of marine 

 abrasion which has an abundance of rocky debris 

 not yet reduced to pebble size by wave action. 



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