. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography BED FORMS 165 under the chosen limits for other variables. The motion is stable if the disturbance is damped, but unstable if it is amplified. In nature the unstable disturbance is ampli- fied until the other variables of the system set some lim- iting condition on the amplification and a new stale of quasi equilibrium is attained. Stability analysis has been successfully applied to the problem of ripple and sand wave formation (, Smith, 1969) a
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography BED FORMS 165 under the chosen limits for other variables. The motion is stable if the disturbance is damped, but unstable if it is amplified. In nature the unstable disturbance is ampli- fied until the other variables of the system set some lim- iting condition on the amplification and a new stale of quasi equilibrium is attained. Stability analysis has been successfully applied to the problem of ripple and sand wave formation (, Smith, 1969) and it seems likely that all bed forms will ultimately prove susceptible to this mode of attack. BASIC MODES OF BED FORM BEHAVIOR. Most bed forms fall into two basic categories: those that are oriented across the flow direction, such as sand waves and ripples, and those that are oriented parallel to the flow direction, such as sand ribbons. These two basic patterns must correspond to two basic patterns within the flow field itself, a transverse pattern in which zones of scour and aggradation alternate down the flow path, and one in which zones of scour and deposition alternate across the flow path (Figs. 5 and 6). There is considerable evidence to indicate that this is the case, although the basic mech- anisms are far from clear. (a). (b) DEVELOPMENT gj^ 2223 ^r lA |K7. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Atlantic Oceanographic and Meteorological Laboratories; Pacific Oceanographic Laboratories; United States. Environmental Science Services Administration. Research Laboratories; Environmental Research Laboratories (U. S. ). Washington, D. C. : U. S. Dept. of Commerce, Environmental Science Services Administration, Research Laboratories : For sale by Supt. of Docs. U. S. G. P. O.
Size: 2333px × 1071px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionamericana, booksponsorlyrasismemb
