N (Turkish.) a—iz geçit; (Yugoslavian.) sutjeska, klisura, soteska. Nackter karst. (German.) See exposed karst. native ground water. Original ground water[16]. Nacktkarst. (German.) See exposed karst. natural arch. 1. A residual portion of the naked karst, bare karst. Karst topography roof of a subsurface karst cavity which developed beneath a temporary cover. has not collapsed. Such a natural arch Some naked karsts develop beneath a may occur as a surface topographic [20] temporary cover of snow (nival karst) or feature, or as a part of a cave system . water[17]. Synonyms: (French.) karst nu; 2. A rock arch or very short natural (German.) oberflächlicher nackter Karst; tunnel; contrasted with natural bridge, [10] (Greek.) gymnon karst; (Italian.) carso which spans a ravine or valley . nudo; (Russian.) goly0 karst or otkryty0 Synonyms: (French.) arche naturelle; karst; (Spanish.) karst desnudo; (German.) natürlisches Gewölbe, (Turkish.) ç2plak karst; (Yugoslavian.) Naturbrücke, Felsfenster, Felsbrücke; goli krš. See also exposed karst. (Greek.) physike apsitha; (Italian.) arco naturale; (Russian.) estestvennij arka; NAPL. Abbreviation for nonaqueous phase (Spanish.) arco natural; (Turkish.) do™al liquid. This term is used to describe the kemer; (Yugoslavian.) prirodni svod, luk, physico- chemical that exist between a naravni obok. See also natural bridge. bulk hydrocarbon and water which results in the two liquids being immiscible with natural bridge. 1. A residual portion of the one another (i.e. little or no mixing of the roof of a subterranean stream which has two liquids occurs.) The interface is a not collapsed and is found bridging a physical dividing surface between the valley. Normally a surface feature, but bulk phases of the two liquids. NAPLs may be used to describe a similar [20] are divided into two categories; LNAPLs occurrence in a cave system . 2. A rock and DNAPLs. See also DNAPL; bridge spanning a ravine and not yet [10] immiscible; LNAPL. eroded away . Synonyms: (French.) pont naturel; (German.) Naturbrücke, nari. Term used in the countries bordering Felsbrücke; (Greek.) physiki gefyra; the Eastern Mediterranean for caliche or (Italian.) ponte naturale; (Russian.) hardpan[20]. See caliche, sabath. estestvennij most; (Spanish.) puente natural; (Turkish.) do™al köprü; narrow. A passage of restricted width (Yugoslavian.) prirodni most, naravni between two caves or hollows in the karst most. See also natural arch. underground; often not readily traversable[20]. Synonyms: (French.) natural levee. A river bank raised by the [16] étroiture; (German.) Enge; (Greek.) steno river’s own depositions . perasma; (Italian.) strettoia; (Russian.) laz; (Spanish.) laminador, gatera; 127 natural load. Sediment carried by a stable neptunian deposits. Younger sediment or stream[16]. sedimentary rock that infills pre-existing cavities, such as grikes, dolines or cave natural tunnel. A nearly horizontal cave passages, in older rocks. The most open at both ends, generally fairly straight common form is a fissure fill, known as a in direction and fairly uniform in cross neptunian dike. Neptunian deposits section[10]. occupy voids in non-karstic as well as karstic rocks, and the combination of void natural water. Water with a mineral and fill may subsequently be buried by content occurring under natural still younger rocks. They may thus conditions. become part of a paleokarst[9]. natural well. (Jamaican.) A vertical shaft nesquehonite. A cave mineral — [11] in limestone, open to the surface and Mg(HCO3)(OH)"2H2O . having water at the bottom; similar to a cenote[10]. Synonym: (Italian.) pozzo nested sinkholes. (American.) See uvala. carsico. net radiation. The sum of incident and neck. A volcanic pipe filled with lava[16]. reflected sun and sky shortwave radiation plus incident and reflected atmospheric necrophage. A scavenger feeding on long-wave radiation[16]. animal carcasses (not prey)[25]. network cave pattern. A type of maze neomorphism. A microscopic texture. A cave characterized by a complex pattern complex of processes whereby a mosaic of repeatedly connected passages in a of finely crystalline carbonate is replaced cave system. In map view, this type of by a coarser (sparry) mosaic without the maze cave appears similar to a city street development of visible porosity. map. It is typically formed by Dominant reactions are the wet solutionally aggressive water infiltrating transformation of aragonite to calcite and through fractures in an overlying recrystallization. The process is insoluble cap-rock thus exhibiting a joint- ‘porphyroid’ where some of the controlled pattern. Synonym: labyrinth. neomorphic crystals are conspicuously larger than those which surround them[20]. neutrality point. The separation point Synonyms: (French.) néomorphisme; between acid and basic solution with a pH (German.) Neomorphismus ?; (Greek.) of 7.0[16]. neomorphismós; (Spanish.) neomorfismo; (Turkish.) neomorfizm. neuromast. One of the individual sense organs that make up the lateral line neoteny. The condition of retaining larval systems of fishes and amphibians[23]. See form and behavior even as a mature also cupula. individual. Certain salamanders in particular are neotenic[23]. 128 nife cell. A rechargeable alkaline battery for nodule. A small, irregularly rounded knot, use with an electric-cap lamp[25]. mass, or lump of a mineral or mineral aggregate, normally having a warty or nip. An undercutting notch in rock, knobby surface and no internal structure, particularly limestone, along a seacoast and usually exhibiting a contrasting between high and low tide levels along composition from the enclosing sediment sea coasts and produced by solution and or rock matrix in which it is embedded erosion. Most common along coasts with (e.g. a chert nodule in limestone.) Most limited tidal variation[20]. Synonyms: nodules appear to be secondary structures (French.) resserrement, étranglement; in sedimentary rocks they are primarily (German.) Kliff ?, Brandungsmarke; the result of post depositional (Greek.) káto engopí vráchou; (Italian.) replacement of the rock and are solco di battigia; (Spanish.) socavación commonly elongated parallel to the marina; (Turkish.) dalga yar2™2 çenti™i. bedding. Nodules can be separated as discrete masses from the host material[1]. nis#a. See aisle. noethphreatic flow. A type of conduit flow niter. A white orthorhombic mineral — that is always laminar[9]. KNO3. It is a soluble crystalline salt that occurs as a product of nitrification in nominal. Used to describe standard sizes 1 most arable soils in hot, dry regions, and for pipe from /8 inch to 12 inches (3.2 in the loose earth forming the floors of mm to 304 mm.) The nominal size is some natural caves[1]. Synonyms: specified on the basis of the inside saltpeter; potassium nitrate. diameter. Depending on the wall thickness, the inside diameter may be less [11] nitrammite. A cave mineral — NH4NO3 . than or greater than the number indicated[6]. nitrocalcite. A cave mineral — [11] Ca(NO3)2"4H2O . nongraded. An engineering term pertaining to a soil or an unconsolidated sediment nitromagnesite. A cave mineral — consisting of particles of essentially the [11] [6] Mg(NO3)2"6H2O . same size . nival karst. Alpine karst[1]. non-point source. 1. Any source, other than a point source, which discharges nivo-karst. A karst-like topography pollutants into air or water[22]. 2. Source produced by the differential chemical originating over broad areas, such as areas weathering beneath snowbanks from of fertilizer and pesticide application and snowmelt containing carbonic acid. It is leaking sewer systems, rather than from found mostly in periglacial areas[1]. discrete points[22]. node point. The intersection point on a non-recording gage. A standard rain gage grid[16]. (8 is standard in U.S.)[16]. 129 normal depth. The depth at which uniform flow occurs in an open channel[16]. normal fault. A fault in which the upper block appears to have moved downward relative to the lower block. Northing. 1. The distance of a point north of the point of origin of the grid of a map, or some abbreviation of it. 2. The south-north component of a survey leg, or of a series of legs, or of a complete traverse; north is positive and south is negative[25]. nothephreatic. Referring to water moving slowly in cavities in the phreatic zone[25]. numbering. Assigning an alphanumeric index to a cave entrance[25]. 130 REFERENCES Series Number 6. British Cave Research Association. London, Britain. 41 pp. 1. Bates, R. L. and J. A. Jackson. 1980. 10. Monroe, W. H. (Compiler). 1970. A Glossary of Geology. American Glossary of Karst Terminology. Geological Institute. Falls Church, Va. Geological Survey Water-Supply Paper 751 pp. 1899-K. U.S. Geological Survey. U.S. Government Printing Office. Washington, 2. Bear, J. 1979. Hydraulics of Groundwater. D.C. 26 pp. McGraw-Hill Inc. New York, NY. 569 pp. 11. Moore, G. W. and G. N. Sullivan. 1978. Speleology: The Study of Caves. Cave 3. Bögli, A. 1980. Karst Hydrology and Books. 2nd Edition. St. Louis, Missouri. Physical Speleology. Springer-Verlag. 150 pp. Berlin, West Germany. 284 pp. 12. Mylroie, J. E. 1984. Hydrologic 4. Daoxian, Y. 1985. New Observations on classification of caves and karst. Tower Karst. Paper presented at the 1st Groundwater as a Geomorphic Agent. R. International Conference on G. LaFleur, Editor. Allen & Unwin. Inc. Geomorphology (Manchester, England). Boston, Mass. pp. 157–172. 14 pp. 13. NSS. 1982. Glossary of caving terms 5. Dreybrodt, W. 1988. Processes in Karst used in this manual. Caving Basics. J. Systems: Physics, Chemistry, and Hassemer, Editor. National Speleological Geology. Springer-Verlag. New York, Society. Huntsville, Ala. pp. 124–125. N.Y. 288 pp. 14. Palmer, A. N. 1972. Dynamics of a 6. Driscoll, F. G. 1986. Groundwater and sinking stream system: Onesquethaw Wells. Johnson Division. St. Paul, Minn. Cave, New York. National Speleological 1089 pp. Society Bulletin. 34. pp. 89–110. 7. Ford, D. C. and P. W. Williams. 1989. 15. Palmer, A. N. 1981. A Geological Guide Karst Geomorphology and Hydrology. to Mammoth Cave National Park.