Sandbanks, sandwaves and megaripples on
Strong currents and sand ripples on the bottom were observed in most of the video lines. The seabed is mostly covered by gravelly sand and sandy gravel (Fig. 16). Patches of sand/shell sand occur in some areas, especially on sandbank B and in the Ac area (Fig. 16, Fig. 17 A). Sandbank A and the sandwaves are mostly covered by …
dbSEABED: Data processing and mining | U.S. Geological …
The dbSEABED program, in part, parses word-based descriptive data such as "brown fine sand with abundant shells; seagrass and some pebbles; whiff of h2s" into numeric, georeferenced data. This process extends the data coverage of the seabed by using words, an important data type characterizing the seabed. While a simplified …
Numerical Simulation of the Effect of Gas Hydrate Formation …
Semantic Scholar extracted view of "Numerical Simulation of the Effect of Gas Hydrate Formation on Liquid-Co2 Leakage Suppression in Sub-Seabed Sand Sediment" by Yosuke Sawano et al.
Analysis of wave-induced liquefaction in seabed deposits …
The possibility of seabed silt liquefaction and its influence factors are analyzed based on the small-amplitude wave theory and the data acquired in laboratory tests. ... 1984. Analysis of wave-induced liquefaction in seabed deposits of sand, Soils and Foundations, 24(3): 85–100. Google Scholar Jeng, D. S., 1997. Wave-induced …
The Role of Sand in Wave Boundary Layers Over Primarily Muddy …
1 Introduction. Terrestrial sediments introduced into coastal regions by rivers are deposited on the seabed, and subsequently may be resuspended by waves and dispersed by shelf processes such as tidal and geostrophic currents (Gao et al., 2016).These process ultimately create the record of long-term net accumulation (L. D. …
Seabed-wave resonance and sand bar growth | Semantic …
The interaction of surface water waves with undulating sea-bed topography is of fundamental importance to coastal engineersand sedimentologists. For example, wave reflection from submerged bars on beaches may provide a mechanism for protecting the beach from further wave attack. Additionally the interaction of surface water waves with …
Seabed-wave resonance and sand bar growth | Nature
The interaction of surface water waves with undulating sea-bed topography is of fundamental importance to coastal engineersand sedimentologists. For example, wave reflection from submerged bars on ...
Understanding Beach Reclamation and Sand Dredging
For beach reclamation, sand dredging helps to replace the sand that is carried away by wave action and currents, essentially 'reclaiming' the beach and preserving its …
Influence of seabed sand wave on hydrodynamic …
ANALYSIS OF WAVE-INDUCED LIQUEFACTION IN SEABED DEPOSITS OF SAND
ABSTRACT To explore the nature of cyclic stress alteration in the seabed deposits of sand due to travelling waves, two-dimensional stress analysis was made for homogeneous elastic half-space subjected to a series of harmonic loads moving on its surface. The analysis indicated that changes in shear stress occur in such a way that, while its …
Seabed pattern dynamics and offshore sand extraction
This thesis aims at understanding the long-term morphodynamic e®ects of large-scale o®shore sand extraction, including the potential interaction with sandbank and sandwave dynamics. To that end, we follow an idealized processbased morphodynamic modelling approach, focusing on a tidally dominated o®shore environment where such …
Seabed mining: Lack of checks keeps PH blind to lasting harm
A lack of checks on seabed mining keeps the Philippines blind to the lasting harm the practice will cause on the environment. ... He said the gulf has become the site of a massive black sand ...
Ice Keel-Seabed Interaction: Numerical Modelling for Sands
Ice Keel-Seabed Interaction: Numerical Modelling for Sands. A large degree of uncertainty still exists in the Arctic where first year, multi-year and glacial (iceberg) ice features pose significant risk to potential oil and gas seabed developments. With advances in computational methods to evaluate ice-soil interaction, it is possible to gain a ...
Influence of seabed sand wave on hydrodynamic …
When H/D > 5, the influence of the seabed sand wave on the resistance and lift force of the submersible can be ignored. ConclusionsThe results of this study provide valuable references for the safety and maneuverability of submersibles. Keywords. submersible seabed sand wave
A detailed seabed signature from Hurricane Sandy revealed …
1. Introduction [2] On 30 October 2012, Hurricane Sandy made landfall near Brigantine New Jersey bringing widespread erosion and damage to the coastline. We have obtained a unique set of high resolution before and after storm measurements of seabed morphology and in situ hydrodynamic conditions (waves and currents) capturing …
dbSEABED
dbSEABED is an ocean information system, directed to a better understanding of the entire world's ocean floor: the seabed - its composition, structure, and physical properties.. The motivation for this long-term project is better human custodianship of the oceans. It does this by increasing public awareness of the oceans, and by helping advances in research, …
Wave-Induced Instability of Seabed beneath Geotextile Sand Containers
Surface waves induce stresses within the seabed that may trigger two major forms of instabilities (de Groot et al. 2006;Gabr 2019a, 2019b): (i) Shear Failure due to wave-induced stresses exceeding ...
Standing Wave-induced Interaction of Pipeline and …
Standing wave-induced interaction of seabed-pipeline in the elasto-plastic saturated sandy seabed has seldom been investigated. By combining standing waves, the Biot's consolidation theory and the sand constitutive model for post-liquefaction behavior by Zhang's research group, an elasto-plastic method was proposed.
Sediment classification and the characterization, …
A geologic substrate is a surface (or volume) of sediment or rock where physical, chemical, and biological processes occur, such as the movement and deposition of sediment, the formation of bedforms, and the attachment, burrowing, feeding, reproduction, and sheltering of organisms. Seabed mapping surveys in the Stellwagen Bank region off Boston, …
Dr Xiaochuan Ma – Exploring the Evolution of Seafloor Sand Dunes
Marine sand is also a vital natural habitat, with countless species depending upon the sandy seabed. Seafloor sand is sculpted by ocean currents into dunes and ridges, similar to wind-blown desert dunes on land. These structures can pose a risk to ship navigation, especially in shallow waters. Understanding the dynamics of sand could help ...
Analytical solution for seepage pressure of multilayered sand seabed …
As shown in Fig. 1, the schematic diagram of the undersea tunnel under combined wave-current interaction, and the simplified calculation model is shown in Fig. 2.The seabed is a multilayered soil mass and the total number of layers including the seabed surface is N, the lth layer is denoted by the symbol L l, the thickness of the lth …
Nonlinear Wave, Composite Breakwater, and Seabed …
The nonlinear dynamic interaction among water waves, composite breakwater and a sand seabed of finite thickness is studied experimentally and numerically in this work. Laboratory experiments were conducted to record the water surface levels around the breakwater and the dynamic pore-water pressure inside its base and seabed …
Soil improvement works for an offshore land reclamation
The Changi East reclamation project was carried out in five phases along the foreshore of the east coast of Singapore. The water depths in the reclaimed area ranged from 5 to 15 …
Analysis of the mechanism of seabed liquefaction induced …
As one of the most serious offshore hazards, wave-induced seabed liquefaction can trigger massive landslides on the ocean floor and pose a great threat to submarine structures (e.g., coastal levees, oil platforms, drilling platforms and seabed pipelines). In view of the complexity and practicability of the problem, this study …
Seismic dynamics of revetment breakwater built on …
This part is used to simulate the reclaimed sand body on the top of some natural coral reefs at engineering in-situ. Moreover, the revetment breakwater is …
Sensitivity analysis of parameters influencing the …
stiness of clay enhanced more slowly. Yang (2009) tested the ice–seabed interaction pro-cess in a sand by conducting the pipeline ice risk assessment and mitigation (PIRAM) program. The author evaluated the subgouge sand displacements, the pressure, the keel reaction forces, the frontal berm and the depth of gouge. The study showed the maximum
Coupled Analysis of Wave, Structure, and Sloping Seabed Interaction
The instability of seabed due to wave-induced instantaneous liquefaction around the marine structure is evaluated and the effect of slope on the extent of liquefied zone is examined. The results indicated that seabed response and the extent of liquefied zone near the structure are reduced with increasing steepness of seabed.
Reclaimed Teak | Noblewood
Reclaimed Teak offers a highly desirable, distressed patina. Our Reclaimed Teak is certified by the Forest Stewardship Council ® to be made from recycled wood. It is both visually stunning and certified good for the environment.
Seabed Resources and Hydrography | Hydro International
coverage bathymetric map revealing seabed features that were previously unknown. With a 's-eye view of the map, the Dutch sector can be divided into several areas with different seabed features. One of the most striking is the extensive sand-wave field. In the south, sand waves with amplitudes between 4 and 6 metres cover the entire …
Land Reclamation
Changi airport was built with over 40 million cubic meters of sand reclaimed from the seabed. Notable examples of coastal land reclamation include Hong Kong, …