481 research outputs found
Sally Goodin [Tellico Style]
No full textTune played by Ebb Collins during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979
Paddy On The Pike
No full textTune played by Ebb Collins & Wilson Douglas during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979. Fiddle Tunes--Georgia
Down Yonder
No full textTune played by Ebb and Zeb Collins during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979
Mary Dear
No full textSong sung by Edward Mashburn with Ebb and Zeb Collins during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979
What A Friend We Have In Jesus
No full textTune played by Ebb and Zeb Collins during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979
When You And I Were Young Maggie
No full textTune played by Ebb Collins, Wilson Douglas & Ira Mullins during the Appalachian South Folklife Festival in Pipestem, West Virginia on July 20th 1979
Wave-Skewness And Current-Related Ebb-Tidal Sediment Transport: Observations And Modeling
No full textA combination of observations and modeling of wave-and current-related sediment transport at the ebb-tidal delta of Ameland, The Netherlands, has been used to examine the dominant sediment transport contributions shaping the ebb-tidal delta. The calibrated model shows a good comparison with the observations for a range of conditions. The results show distinctly different transport modes and directions for current and wave-dominated conditions respectively, with a significant contribution owing to the skewness of the waves emphasizing the importance of wave non-linearity in shaping the ebb-tidal delta.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Coastal EngineeringEnvironmental Fluid Mechanic
Morphodynamic Modelling of the Ameland Ebb-Tidal Delta: An Assessment of the 2018 - 2019 Pilot Nourishment
No full textEbb-tidal deltas play a key role in the morphology of barrier coastlines and tidal inlet systems as they serve as a natural source of sediment. They are typified by a dynamic morphology that interacts with the adjacent coastlines and sponsors a unique ecological habitat. Under increasing socio-economic, ecological and climate-induced constraints, it becomes imperative to obtain a better understanding of the evolution of ebb-tidal deltas in order to maintain and preserve these morphological features in the near-future time horizon. An increased interest has therefore been raised to understand, quantify and predict the development of ebb-tidal deltas. In the context of developing a future-proof coastal management and maintenance strategy, the efficiency of ebb-tidal delta nourishments has been further investigated in research programmes such as Coastal Genesis 2.0. For the Ameland inlet, this entailed the construction of a 5 million m3 pilot nourishment over the course of March 2018 to February 2019 and subsequent monitoring in the years following. This research investigates the impact of this pilot nourishment on the natural behaviour of the Ameland ebb-tidal delta. The second goal is to build further knowledge on the modelling capabilities of present state-of-the-art models for the Ameland ebb-tidal delta.To this end, a process-based Delft3D model is applied to hindcast the morphological development of the ebb-tidal delta with a particular interest in the evolution of ebb-shields and -chutes over the course of 2005 to 2020. It is identified that the representation of the wave-induced processes is key for capturing the development of ebb-shields and -chutes in the model predictions. Therefore, we applied and experimented with an updated nonlinear wave orbital velocity parameterisation and assessed its contribution to the modelling performance. This thesis demonstrates that the evolution of ebb-shields and chutes on the outer delta is contingent on its initial presence in the initial bathymetry. Hence, the initiation of ebb-shield development is not inherited in the model response. These insights have been integrated and synthesised to assess the application of the present state-of-the-art model as a forecasting tool for the morphological development of ebb-tidal delta nourishments.Ultimately, it is shown that a model using schematised boundary conditions and an efficient morphological updating scheme is able the predict the yearly-averaged development of the pilot nourishment on the ebb-tidal delta. It is demonstrated that the 2019 pilot nourishment only locally influences the behaviour of the Ameland ebb-tidal delta. Nourished sediment is likely to be redistributed along the ebb-shields, contributing on the long-term to the sediment exchange process with the downdrift coast of Ameland. The location of the ebb-tidal delta nourishment is thereby important for the sediment exchange process and the development of local features. Placing ebb-tidal delta nourishments to the south of the Westgat invokes a primary sediment exchange between the coast of Terschelling and surrounding morphological features. A secondary readjustment of the Westgat thereby influences the development of the ebb-shields and -chutes. Constructing an ebb-tidal delta nourishment north of the Westgat results in a sediment exchange between the local ebb-shields and the downdrift coast of Ameland. Our results also demonstrate that an increase in the pilot nourishment construction height enhances the redistribution of sediment along the ebb-shields.Lastly, this study identifies further opportunities for improving medium-term morphodynamic models for the Ameland inlet by incorporating time-dependent boundary conditions including new transport formulations such as SANTOSS.Civil Engineerin
Morphology of the Eastern Scheldt ebb tidal delta
No full textThe Eastern Scheldt tidal basin and its ebb tidal delta have changed drastically in the recent centuries under the influence of natural processes and human interventions. A Storm Surge Barrier, one of constructions within framework of Delta Project in the Eastern Scheldt, is considered as the largest impact to changes in hydrodynamics and morphology of the ebb tidal delta. The barrier was built in 1987 to maintain the tide and to protect the area from flooding. The barrier closes under severe storm surge conditions and remains open during normal conditions to preserve the tide-dominated character of the ecosystem. However, this storm surge barrier caused a reduction of tidal volume and tidal current in the Eastern Scheldt. Since 1987, there has been a remarkable reduction of the tidal prism by 30%, of the average tidal range by 12% and of the average tidal current velocities by 33%. As a result, sediment export from the basin towards its ebb tidal delta has ceased. This led and still to changes in morphology of the ebb tidal delta. In order to adapt to changes in tidal volume, the tidal channels become sinks of sediment and this sediment has been and still is taken from the tidal shoals nearby. Sediment volume of these shoals therefore has decreased drastically. The deposition in channels and erosion on the shoals caused a number of negative effects to ecology, safety, navigation, recreations and fishery in the Eastern Scheldt. To analyse the morphological developments of the ebb tidal delta before, during and after the implementation of the Storm Surge Barrier in the Eastern Scheldt, bathymetry maps which present the changes in deposition and erosion parts in the ebb tidal delta in every four years (from 1960 to 2004) were used. In summary, the morphology of the Eastern Scheldt ebb tidal delta experienced enormous changes due to the Delta Project. These changes comprise shoaling and reorientation of channels- from updrift to downdrift (northward) migration of channels, landward migration of shoals, development and diminishing of ebb and flood chutes and development of scour holes near the entrance of the storm surge barrier. As a result, it would take a long time (centuries) to establish a new dynamic equilibrium between hydraulic conditions and geomorphology in the Eastern Scheldt inlet.CoMEM - Coastal and Marine Engineering and ManagementHydraulic EngineeringCivil Engineering and Geoscience
A novel approach to mapping ebb-tidal delta morphodynamics and stratigraphy
No full textEbb tidal deltas (ETDs) are highly dynamic features of sandy coastal systems, and coastal management concerns (e.g., nourishment and navigation) present a pressing need to better describe and quantify their evolution. Here we propose two techniques for leveraging the availability of high-resolution bathymetric surveys to generate new insights into the dynamics and preservation potential of ebb-tidal deltas. The first technique is conformal mapping to polar coordinates, using Ameland ebb-tidal delta in the Netherlands as a case study. Since the delta tends to evolve in a clockwise direction around the inlet, this approach provides an improved quantification and visualization of the morphodynamic behaviour as a timestack. We clearly illustrate the sediment bypassing process and repeated rotational migration of channels and shoals across the inlet from updrift to downdrift coasts. Secondly, we generate a decadal scale (1975–2021) stratigraphic model from the differences between successive bathymetries. This stratigraphy showcases the delta's depositional behaviour through space and time, and provides a modern analogue for prehistoric ebb-tidal deltas. During the surveyed period, inlet fills form the largest and most stable deposits, while the downdrift swash platform is the most stable structure over longer periods. Together, these approaches provide new perspectives on ebb-tidal delta dynamics and preservation potential which are readily applicable to other sites with detailed bathymetric data. These findings are valuable at annual to decadal timescales for coastal management (e.g., for planning sand nourishments) and also at much longer timescales for interpreting stratigraphy in ancient rock records.Environmental Fluid MechanicsCoastal Engineerin
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