Download or read book Sand Waves and Tidal Channels in the Entrance to Chesapeake Bay written by John C. Ludwick and published by . This book was released on 1970 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sand waves 5-12 feet in height and 200-1200 feet in length occur in water 25-50 feet deep in the sand bank and tidal channel area of the entrance to Chesapeake Bay. Most waves are asymmetrical in transverse profile, some facing with ebb currents, others facing with flood currents, depending which is dominant at a given place. Steep slopes on the various waves range from 4 to 31 degrees and average 12 degrees. The sand waves occur in association with tidal channels and especially on the flanks of shoals that form channel boundaries. Migration of sand waves, judged from their facing direction, is a bed sediment transport mechanism by which sand is moved up onto shoals. Many large shoals of the area occur between ebb-dominated and flood-dominated channels. This implies the existence of net circulation loops of water and sediment in cells located over shoals. The action of such cells is to trap sediment. Other ebb-flood shear zones may mark sites of future shoaling in the entrance. (Author).
Download or read book Sand Waves in Tidal Channels written by Shelley Johnston Whitmeyer and published by . This book was released on 2007 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sequential mapping at Moriches Inlet, NY, showed that bedforms at this site are 39 cm high and moribund. Theoretically, bedforms of this height should only form when flow velocities reach 0.8 m/s. However, maximum measured velocities during the study were only 0.6 m/s. It is hypothesized that the bedforms become active during storms when strong winds or storm-induced surges increase the tidal range and the ensuing tidal currents. A two-dimensional, depth-integrated hydraulic model indicates that a current velocity of 80 cm/s will occur when the tidal range exceeds 1.6 m, ∼1.0 m greater than the typical spring tidal range. Regression analysis of hydraulic parameters measured in the field confirms this.
Download or read book Migration of Tidal Sand Waves in Chesapeake Bay Entrance written by John C. Ludwick and published by . This book was released on 1971 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Subtidal sand waves occur atop shoals and on shoal margins in the northern part of the tidal entrance to Chesapeake Bay, Virginia. Wavelength ranges from 200-800 ft; height ranges from 5-11 ft. All major slopes are 2-3 degrees, far less than the angle of repose of the constituent sediment. In flood-dominated tidal channels, sand waves are asymmetrical and face landwards; in ebb-dominated tidal channels and atop most banks, sand waves face seawards. Where near-bottom flood and ebb tidal currents are equal in time-velocity impulse, sand waves of symmetrical trochoidal profile are developed. Data from 21 successive echo-sounding profiles taken over a 17-month period show that the seaward-facing asymmetrical sand waves range from 115 to 492 ft/year. (Author).
Download or read book Marine Sand Waves in El Infiernillo Channel Gulf of California written by Paul Milton Merifield and published by . This book was released on 1970 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: El Infiernillo Channel, averaging 5 km in width, separates Tiburon Island from the Sonoran mainland. Ebb currents flowing south from the channel form sand waves and tidal current ridges in Kunkaak Bay in water depths of less than 3 m. Surface ebb currents up to 1.7 knots, producing Froude Numbers of about 0.27, were measured. The sand waves have wavelengths ranging from 12 m to 75 m and amplitudes from 0.30 m to 0.75 m. The sediment consists of well-sorted, coarse-grained sand; size-frequency distributions of the sediment samples are positively skewed. No relationship was found between sand-wave morphology and grain size in Kunkaak Bay. In Agua Dulce Bay at the north end of the channel, sand waves are developed in fine-grained sand. Size-frequency distributions of the sediment samples are negatively skewed. The sand on the crests was found to be coarser in grain size and less negatively skewed than the sand in the troughs. The sand waves have wavelengths of 180 m to 250 m and amplitudes from 1.1 m to 1.5 m. The steep sides face with the flood tide, but the sand waves were not forming during the periods of observation. (Author).
Download or read book Principles of Tidal Sedimentology written by Richard A. Davis Jr. and published by Springer Science & Business Media. This book was released on 2011-10-20 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive, contemporary review of tidal environments and deposits. Individual chapters, each written by world-class experts, cover the full spectrum of coastal, shallow-marine and even deep-marine settings where tidal action influences or controls sediment movement and deposition. Both siliciclastic and carbonate deposits are covered. Various chapters examine the dynamics of sediment transport by tides, and the morphodynamics of tidal systems. Several chapters explore the occurrence of tidal deposits in the stratigraphic context of entire sedimentary basins. This book is essential reading for both coastal geologists and managers, and geologists interested in extracting hydrocarbons from complex tidal successions.
Download or read book Sand Waves written by Douglas R. Levin and published by . This book was released on 1992 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seafloor Geomorphology as Benthic Habitat written by Peter Harris and published by Elsevier. This book was released on 2011-11-28 with total page 947 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation This book provides a synthesis of seabed geomorphology and benthic habitats based on the most recent, up-to-date information. Case studies from around the world are presented.
Download or read book The Applied Dynamics of Ocean Surface Waves written by Chiang C. Mei and published by World Scientific. This book was released on 1989 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to present selected theoretical topics on ocean wave dynamics, including basic principles and applications in coastal and offshore engineering, all from the deterministic point of view. The bulk of the material deals with the linearized theory.
Download or read book Formation and Evolution of Multiple Tidal Inlets written by Aubrey and published by American Geophysical Union. This book was released on 1993 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coastal estuarine and Nearshore Processes written by Evelyn Sinha and published by . This book was released on 1974 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Ecology of Sandy Shores written by A.C. Brown and published by Elsevier. This book was released on 2010-07-27 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Ecology of Sandy Shores provides the students and researchers with a one-volume resource for understanding the conservation and management of the sandy shore ecosystem. Covering all beach types, and addressing issues from the behavioral and physiological adaptations of the biota to exploring the effects of pollution and the impact of man's activities, this book should become the standard reference for those interested in Sandy Shore study, management and preservation. More than 25% expanded from the previous edition Three entirely new chapters: Energetics and Nutrient Cycling, Turtles and Terrestrial Vertebrates, and Benthic Macrofauna Populations New sections on the interstitial environment, seagrasses, human impacts and coastal zone management Examples drawn from virtually all parts of the world, considering all beach types from the most exposed to the most sheltered
Download or read book Offshore Tidal Sands written by A. H. Stide and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1970s a start was made on a broad review of what was known or could be surmised about sedimentation by strong tidal currents on modern continental shelves. This task was initiated because of the need to define the next phase of research in this field by the Marine Geology Group of the Institute of Oceano graphic Sciences. Related indications of the longer term evolution of the deposits were sought by close reference to the nature of modern tidal currents and the supposedly offshore tidal deposits of ancient seas. As the review grew in completeness it became of increasing relevance to a wider audience so it was amalgamated with the new results and shaped as a book. The fruits of the long-continued discussions within and outside the Geology Group have served to improve understanding of the processes and products of offshore tidal current sedimentation. On the other hand, the discussions have blurred the parts played by the people concerned. This applies to all chapters in varying degrees, but is especially true for Chapters 3, 4 and 5. The authorship attributed to each chapter therefore seeks to reflect those who were most con cerned with it.
Download or read book Waves and Tides written by Robert Christopher Hamlyn Russell and published by Hutchinson's Scientific and Technical Publications. This book was released on 1970 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Sand Waves in the Panama City Florida Entrance Channel written by W. Jeff Lillycrop and published by . This book was released on 1989 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Committee on Tidal Hydraulics Report written by and published by . This book was released on 1968 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sand Waves in a Pristine Estuary written by B. Ravindranath Baliga and published by . This book was released on 1978 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stochastic and the Fourier theories for sand waves developed by Lee(11) and Hino(6), respectively, for unidirectional flows are extended in order to estimate the rate of sediment turnover (RST) under oscillatory flows in the South Slough estuary, Coos Bay, Oregon. Data were collected by a mechanical and a sonic profiler. Histograms are given for the distributions of the elevations of deposition and erosion for sand wave data measured by the mechanical profiler. It may be observed from these distributions that the Gaussian assumption required for the application of the stochastic theory is not satisfied. The parameters for the step length distribution are estimated for only one elevation of deposition and erosion and the theoretical Gamma distribution is computed. Wave number amplitude spectra are estimated from the sonic profiler sand wave data. The maximum amplitude in the sand waves which were measured in the South Slough estuary lie in the fundamental harmonic component; while for the Coos Bay main channel, the spectral amplitudes for the sand waves are dispersed over a wider band of wave numbers. Due to the weak hydrodynamic influence, the sand waves in the South Slough estuary are still in the initial stage of their growth and it may not be possible to estimate RST in the South Slough estuary by the stochastic method outlined by Lee(11). Due to the strong tidal influence and/or ship disturbances, the sand wave spectral amplitudes are well dispersed for the Coos Bay main channel data and it is possible to estimate the RST in the main channel from a wave number spectrum using a transformation between wave numbers and wave frequencies.
Download or read book The Stability of Sand Waves in a Tidally influenced Shipping Channel Tampa Bay Florida written by John Willis Gray and published by . This book was released on 2018 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tidally-influenced sandwaves are common coastal features present in various settings, including shipping channels. The main shipping channel in Tampa Bay under the Bob Graham Sunshine Skyway Bridge (a.k.a. the Skyway Bridge) contains such sandwave bedforms. Between the years 2000 and 2017, these bedforms have been surveyed with multibeam echosounders (MBES) on 21 occasions with ranging coverage and quality of returns. Surveys between 2000 and 2009 used a 300 kHz Kongsberg EM3000; surveys between 2015 and 2017 used a 400 kHz Reson Seabat 7125. For comparable surveys, bathymetry, backscatter, slope, curvature, planform curvature, and profile curvature maps were created and analyzed. Spectral analyses were completed on the same cross-section for usable surveys, providing a period and amplitude for the bedforms. Sediment samples were taken in September 2015 using a Shipek grab. The sediment samples were analyzed for grain size and carbonate content. A bottom-mounted ADCP recorded velocity data semi-continuously over the same time period. These data were analyzed in an effort to investigate the forcing mechanisms that influence the bedform morphology.
