(Ellis 1978) bench mark (BM)Ī fixed physical object or mark used as reference for a vertical datum. Some beaches have no berms, others have one or several. Nearly horizontal portion of the beach or backshore formed by the deposit of materials by wave action. A beach includes foreshore and backshore. Zone of unconsolidated material that extends landward from the low water line to the place where there is marked changes in material or physiographic form, or to the line of permanent vegetation (usually the effective limit of storm waves). Science of measuring water depths (usually in the ocean) in order to determine bottom topography.
AĬombination of the low-water line and closing lines across the mouths of inland water bodies. The line from which maritime zones are measured. (Ellis 1978) bankĮdge of a cut or fill the margin of the watercourse an elevation of the seafloor located on a continental shelf or an island shelf and over which the depth of water is relatively shallow but sufficient for safe surface navigation (reefs or shoals, dangerous to surface navigation may arise above the general depths of a bank). That part of the beach that is usually dry, being reached only by the highest tides, and by extension, a narrow strip of relatively flat coast bordering the sea. Neither of these changes works a change in the riparian boundary. The loss of lands bordering on the seashore by sudden or violent action of the elements, perceptible while in progress a sudden and rapid change in the course and channel of a boundary river. This line represents the intersection of the appropriate datum on the outer limits of vegetation and appears to the navigator as the shoreline. Line drawn on a map or chart in lieu of a mean high water line (MHWL) or the mean water level line (MWLL) in areas where either may be obscured by marsh, mangrove, cypress, or other type of marine vegetation. Accuracy relates to the quality of a result and is distinguished from precision which relates to the quality of the operation by which the result is obtained. (Shalowitz 1964) accuracyĭegree of conformity with a standard.
Accretion is the act, while alluvion is the deposit itself. This may be the result from a deposit of alluvion upon the shore, or by a recession of the water from the shore. The gradual and imperceptible accumulation of land by natural causes, as out of the sea or a river. The current can still be flooding after stand has been passed at our given point and the level has started to fall.A-C| D-F | G-I | J-M | N-P | R-T | U-W A accretion Further up the bay or river, the tide will not have reached its maximum height and water must therefore continue to flow in so that it can continue to rise. High water at a given point simply means that the level there will not get any higher. Tidal currents do not automatically slack and reverse direction when tide levels stand at high or low water. The time of occurrence of slack is not the same as the time of stand, when the vertical rise or fall of tide has stopped. Conversely, a tidal current ebbs when the flow is seaward and the water levels fall.Īs these currents reverse, there are brief periods of no discernible flow, called slack, or slack water. "A tidal current is said to flood when it flows in from the sea and results in higher tidal stages. Rivers and tributaries that feed the bay." Have an overlaid outflow from the bay due to the Have high/low tide concurrent with slack is that we Well here isĪn example where the slack and high tide does notĬoincide. The entrance it would slow down more and more.Įventually the current would stop (slack) but the tide Now if the river ran a bit slower theĬurrent would start to slow down as the tide came inįrom the ocean and as the tide continued to rise at So you have high tide and low tideĪnd no slack. The river but never have slack as the river is too fast To the sea it is likely that you would find tide in
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