F along which there has been displacement of the two sides relative to one another [6] fabric. The orientation in space of the parallel to the fracture . This elements composing a rock substance. displacement may be of a few centimeters or many kilometers. See also joint fault facet. See scallop. set; joint fault system. facies. The lithologic appearance of a fault breccia. The assemblage of broken rock[16]. rock fragments frequently found along faults. The fragments may vary in size facies change. The change in appearance from inches to feet. that occurs when one lithologic unit ends and a new one is encountered. fault cave. A cave developed along a fault or fault zone[10]. failure. In rocks, failure means exceeding of the maximum strength of a rock or fault gouge. A clay-like material occurring exceeding the stress or strain requirement between the walls of a fault as a result of of a specific design. the movement along the fault surfaces. fall. The gross slope of a river[16]. fault line. The intersection of a fault with the surface of the earth or any other plane [16] false floor. A remnant of a sheet of of reference . flowstone, originally deposited on clastic sediments that were subsequently washed fault plane. A plane on which dislocation [16] out from beneath. False floors may and relative movement has taken place . survive as a complete bridge between passage walls or just as projecting ledges. fault scarp. An elevation formed by They may be thin and easily broken or movement of blocks along a fault [16] thick and very strong[9]. plane . farangothes ipoyios thiavasis. See aisle. fault zone. A zone with numerous small parallel faults[16]. fathometer. A water depth measuring device[16]. feeding tube. In karst terrane, a more or less straight and waterbearing fault. 1. A fracture in the earth’s crust, underground gallery of regular cross- across which relative rock movement has section. Synonyms: (French.) tunnel; taken place, or continues to take place. (German.) Stro4mungsrohr, Karstgerinne; Fault planes commonly guide vertical or (Greek.) karstikos ypoyios agogos; sub-vertical shafts in caves, as well as (Spanish.) tubo; (Turkish.) akarsu guiding sub-horizontal or oblique mecras2; (Yugoslavian.) vodonosni rov. passages within the confines of the fault See also stream tube. plane[9]. 2. A fracture or fracture zone 73 feldspars. A very common group of rock peak density, in contrast to the Western forming minerals[16]. classification by hill shape. Fenglin is therefore almost the equivalent of tower fengcong; fengcong karst. (Chinese.) 1. A karst; its hills have very steep or vertical karst, conspicuous in China, that is walls, and may have a height/width ratio identified by its clustered limestone hills. greater than four. The limestone hills rise Fengcong (pronounced ‘fungston’), which above level, alluviated plains, and the translates as ‘peak cluster’, is a mature finest fenglin karst around Yangshuo, karst normally developed during long Guangxi, in southern China, is one of the uninterrupted periods of rapid dissolution world’s most dramatic landscapes. The in wet tropical environments with high classification by hill density means that levels of biogenic soil carbon dioxide. low residual cones scattered across a plain The Chinese classify karst by the hill or are also referred to as fenglin by the peak density, in contrast to the Western Chinese[9]. 2. Tower karst characterized classification by hill shape. Fencong is as peak forest because the individual almost the equivalent of cone karst; its towers appear as isolated groups on a closely packed hills are conical rather plain. Dry valley networks separate than hemispherical, with intervening individual towers[4]. See also fengcong; dolines and disjointed valleys. The major fungling; mogote; tower karst. occurrences are in Guizhou and Guangxi, in southern China. Some cones in ferghanite. A cave mineral — [11] Guangxi are so steep that they have been U3(VO4)2"6H2O . termed fengcong tower karst, but this [9] [16] concept is best avoided . 2. Tower karst ferric oxide. Rust; hematite (Fe2O3) . characterized as peak cluster because the individual karst towers appear to be ferrito zone. Zone of iron oxide grouped together in clusters. Closed accumulation in soil under humid climate depression among the peaks are conditions[16]. common[4]. See also fenglin; fungling; mogote; tower karst. Fickian diffusion. The spreading of solutes from regions of highest to regions of fenglin; fenglin karst. (Chinese.) 1. A lower concentrations caused by the karst, conspicuous in China, that is concentration gradient. In slow moving identified by its isolated limestone hills. ground water, this is the dominant mixing Fenglin (pronounced ‘funglin’) translates process[22]. from Chinese as ‘peak forest’, and is distinguished from fengcong. Both fissure. Any discontinuity within the rock fenglin and fengcong are mature karst mass that is either initially open or normally only developed by long capable of being opened by dissolution to uninterrupted periods of rapid dissolution provide a route for water movement. in wet tropical environments with high Fissures in this sense, applied generally in levels of biogenic soil carbon dioxide. karst, therefore include the primary The Chinese classify karst by the hill or sedimentary bedding planes as well as 74 tectonic faults and joints. More out to become wells or vertical shafts[10]. specifically, the term has been used to See also vertical shaft. describe voids with average dimensions from 10 to 100mm[9]. See also conduit; Flachkarren. (German.) See clint. fracture. flank. A limb of a fold[16]. field capacity; field moisture capacity. See specific retention. flash flood. A relatively short but very intense flood[16]. field survey. Measurements taken in the field[16]. flattener. A cave passage, which though wide, is so low that movement is only field test. A test run in the field under possible in a prone position[10]. See also normal field conditions[16]. crawl. field velocity of ground water. Actual flexure. A bend in a stratum with one flank interstitial velocity of ground water[16]. or limb only[16]. fill terrace. An elevated valley surface flint. A concretionary form of silica, similar formed by aggregation[16]. to chert, that occurs in chalk as tabular sheets and layers of irregularly shaped fine gravel. Rock aggregates of 1–2 mm nodules. Being very hard and relatively diameter[16]. insoluble, flint tends to stand out from chalk cliffs. Flint-rich horizons may also fine sand. A silicon dioxide material with a influencer the inception of bedding- grain diameter of 0.1– 0.25 mm[16]. related dissoluational conduits in chalk[9]. finite difference method. A numerical float gage. A device that indicates or method used to approximate the solution records water levels with a float[16]. of partial differential equations[16]. floating pan. An evaporation pan floating finite element method. A numerical in a water body with drum floats[16]. method used to approximate the solution of partial differential equations. floe calcite. Very thin film of pure calcium carbonate floating on the surface of a firn. Compacted granular snow[16]. subterranean pool of very calm water[10]. firstkarren. (Austrian.) See Rillenkarren. flood. A high river flow overtopping banks. fissure. An open joint or crack in rocks[16]. flood crest. The peak of a flood wave[16]. fissure cave. A narrow vertical cave or cave flooding method. A recharge method by passage along a fissure. Fissures widen flooding a recharge area[16]. 75 floodmarks. The marks left on fixed flow-mass curve. 1. A mass curve with objects by flood waters[16]. runoff discharge as a hydrologic quantity[16]. 2. The integral of the curve flood plain. The surface or strip of of a hydrograph[16]. relatively smooth land adjacent to a river channel, constructed by the present river flow line. The general path that a particle of and covered with water when the river water follows under laminar flow overflows its banks. It is built of conditions[22]. Flow lines are usually alluvium carried by the river during drawn perpendicular to equipotential floods and deposited in the sluggish water lines. See also equipotential lines. beyond the influence of the swiftest current[6]. flow net. 1. A graphical representation of flow lines and equipotential lines for flood profile. A continuous line two-dimensional, steady-state representing the water surface for a given ground-water flow[22]. 2. A net of rate of flow[16]. orthogonal streamlines and equipotential lines applied in the graphical solution of flood water. Water that has overflowed its Laplace’s equation[16]. confines; the water of a flood[1]. flow path. The subsurface course a water flood-water zone. See epiphreas. molecule or solute would follow in a given ground-water velocity field. flood wave. A rise in the stage of a stream that culminates in a crest before flow rate. Volumetric rate of flow[16]. receding[1]. flow, steady. A characteristic of a flow floor pocket. See pocket. system where the magnitude and direction of specific discharge are constant in time flow, base. See base flow. at any point[22]. See also flow, unsteady. flow, creep. Flow with a creeping motion flow, uniform. A characteristic of a flow where inertial terms have been system where specific discharge has the dropped[16]. same magnitude and direction at any point[22]. flow, critical. See critical flow. flow, unsteady. A characteristic of a flow flow duration curve. A curve of system where the magnitude and/or cumulative streamflow versus the direction of the specific discharge corresponding per cent of time[16]. changes with time. Synonymous with nonsteady flow. See also flow, steady. flow gage. A gage used to measure flow rate[16]. See also gage. flow velocity. See specific discharge. 76 flower.