subject:(bedforms)

University of Limerick

1. Fannon, James S. Mathematical modelling of subglacial bedform formation and dense granular flows.

Degree: 2020, University of Limerick

►

peer-reviewed

Subglacial bedforms,which include drumlins,ribbed moraine,and mega scale glacial lineations, are ubiquitous features in regions which were once covered by ice sheets, and their genesis… (more)

Subjects/Keywords: subglacial bedforms; mathematics; formation

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APA (6^th Edition):

Fannon, J. S. (2020). Mathematical modelling of subglacial bedform formation and dense granular flows. (Thesis). University of Limerick. Retrieved from http://hdl.handle.net/10344/9298

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fannon, James S. “Mathematical modelling of subglacial bedform formation and dense granular flows.” 2020. Thesis, University of Limerick. Accessed January 23, 2021. http://hdl.handle.net/10344/9298.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fannon, James S. “Mathematical modelling of subglacial bedform formation and dense granular flows.” 2020. Web. 23 Jan 2021.

Vancouver:

Fannon JS. Mathematical modelling of subglacial bedform formation and dense granular flows. [Internet] [Thesis]. University of Limerick; 2020. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10344/9298.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fannon JS. Mathematical modelling of subglacial bedform formation and dense granular flows. [Thesis]. University of Limerick; 2020. Available from: http://hdl.handle.net/10344/9298

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin

2. Norman, Francis Alexander, IV. An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport.

Degree: MSin Geological Sciences, Geological Sciences, 2013, University of Texas – Austin

URL: http://hdl.handle.net/2152/22184

► Hyporheic flow influences both biogeochemical cycling in streambeds as well as streambed ecology. Some biogeochemical processes may be temperature dependent; therefore, heat transport associated with… (more)

Subjects/Keywords: Hydrogeology; Hyporheic zone; Bedforms

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APA (6^th Edition):

Norman, Francis Alexander, I. (2013). An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/22184

Chicago Manual of Style (16^th Edition):

Norman, Francis Alexander, IV. “An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport.” 2013. Masters Thesis, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/22184.

MLA Handbook (7^th Edition):

Norman, Francis Alexander, IV. “An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport.” 2013. Web. 23 Jan 2021.

Vancouver:

Norman, Francis Alexander I. An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport. [Internet] [Masters thesis]. University of Texas – Austin; 2013. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/22184.

Council of Science Editors:

Norman, Francis Alexander I. An experimental assessment of the influence of bedforms on coupled hyporheic flow and heat transport. [Masters Thesis]. University of Texas – Austin; 2013. Available from: http://hdl.handle.net/2152/22184

University of Oregon

3. Gardner, Kevin. Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California.

Degree: MS, Department of Geological Sciences, 2020, University of Oregon

URL: https://scholarsbank.uoregon.edu/xmlui/handle/1794/25251

► Contrasting hypotheses for the depositional paleoenvironments of the late Miocene to early Pliocene southern Bouse Formation currently hinder progress toward a consensus on tectonic and… (more)

Subjects/Keywords: Carbonates; Compound Bedforms; Sedimentology; Stratigraphy; Tidal

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APA (6^th Edition):

Gardner, K. (2020). Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California. (Masters Thesis). University of Oregon. Retrieved from https://scholarsbank.uoregon.edu/xmlui/handle/1794/25251

Chicago Manual of Style (16^th Edition):

Gardner, Kevin. “Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California.” 2020. Masters Thesis, University of Oregon. Accessed January 23, 2021. https://scholarsbank.uoregon.edu/xmlui/handle/1794/25251.

MLA Handbook (7^th Edition):

Gardner, Kevin. “Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California.” 2020. Web. 23 Jan 2021.

Vancouver:

Gardner K. Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California. [Internet] [Masters thesis]. University of Oregon; 2020. [cited 2021 Jan 23]. Available from: https://scholarsbank.uoregon.edu/xmlui/handle/1794/25251.

Council of Science Editors:

Gardner K. Stratigraphy, Sedimentology, and Tidal Processes of the Late Miocene to Early Pliocene Southern Bouse Formation, Southeast Palo Verde Mountains, California. [Masters Thesis]. University of Oregon; 2020. Available from: https://scholarsbank.uoregon.edu/xmlui/handle/1794/25251

Universidade do Rio Grande do Norte

4. Soares, Camila Hyslava Campos. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .

Degree: 2012, Universidade do Rio Grande do Norte

URL: http://repositorio.ufrn.br/handle/123456789/18827

► The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are… (more)

▼ The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are inserted in a semi-arid climate area and form the mouth of the hydrographic basin of the Piranhas-Açu river, that represent the discharge of the largest watershed in the state. They are embedded in an environment consisting of a fluvial-marine floodplain, mangrove ecosystem, sandbanks, fields of dunes, spits and sandy beaches. Adjacent to the natural units are the main local socioeconomic activities (oil industry, salt industry, shrimp farming, fishing and tourism) are dependent on this river and its conservation. The environmental monitoring is necessary because it is an area under constant action of coastal processes and at high risk of oil spill. The acquisition and interpretation of hydrodynamic, sonographic and sediment data was conducted in two campaigns, dry season (2010) and rainy season (2011), using respectively the current profiler ADCP Doppler effect, the side-scan sonar and Van Veen sampler. In these estuaries: Açu, Cavalos and Conchas were identified the following types of bedforms: flatbed and Dunes 2-D and 3-D (small to medium size), generated at lower flow regime (Froude number <1). Structures such as ripples were observed in the Açu estuary mouth. The higher values of flow discharge and velocity were recorded in the Açu estuary (434,992 m³.s-¹ and 0,554 m.s-¹). In rainy season, despite the record of highest values of discharge and flow velocities at the mouth, the energy rates upstream did not differ much from the data of the dry season. However, in all estuaries were recorded an increase in speed and flow, with reservation to the flow in the Açu estuary and flow at the mouth of the Conchas estuary. Sediment grain sizes tend to increase towards the mouth of the estuary and these ranged from very fine sand to very coarse sand, medium sand fraction being the most recurrent. Based on the data acquired and analyzed, the estuaries Açu, Cavalos and Conchas are classified as mixed , dominated by waves and tides. According to their morphology, they are classified as estuaries constructed by bar and according to the classification by salinity, estuaries Conchas and Cavalos were ranked as hypersaline estuaries, and Açu as hypersaline and vertically well mixed type C Advisors/Committee Members: Vital, Helenice (advisor), CPF:31481981404 (advisor), http://lattes.cnpq.br/3595069999049968 (advisor).

Subjects/Keywords: Formas de fundo. Levantamento sonográfico. ADCP; Bedforms. Side scan sonar. ADCP

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Soares, C. H. C. (2012). Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . (Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18827

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Soares, Camila Hyslava Campos. “Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .” 2012. Thesis, Universidade do Rio Grande do Norte. Accessed January 23, 2021. http://repositorio.ufrn.br/handle/123456789/18827.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Soares, Camila Hyslava Campos. “Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .” 2012. Web. 23 Jan 2021.

Vancouver:

Soares CHC. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . [Internet] [Thesis]. Universidade do Rio Grande do Norte; 2012. [cited 2021 Jan 23]. Available from: http://repositorio.ufrn.br/handle/123456789/18827.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Soares CHC. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . [Thesis]. Universidade do Rio Grande do Norte; 2012. Available from: http://repositorio.ufrn.br/handle/123456789/18827

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Rio Grande do Norte

5. Soares, Camila Hyslava Campos. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .

Degree: 2012, Universidade do Rio Grande do Norte

URL: http://repositorio.ufrn.br/handle/123456789/18827

► The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are… (more)

▼ The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are inserted in a semi-arid climate area and form the mouth of the hydrographic basin of the Piranhas-Açu river, that represent the discharge of the largest watershed in the state. They are embedded in an environment consisting of a fluvial-marine floodplain, mangrove ecosystem, sandbanks, fields of dunes, spits and sandy beaches. Adjacent to the natural units are the main local socioeconomic activities (oil industry, salt industry, shrimp farming, fishing and tourism) are dependent on this river and its conservation. The environmental monitoring is necessary because it is an area under constant action of coastal processes and at high risk of oil spill. The acquisition and interpretation of hydrodynamic, sonographic and sediment data was conducted in two campaigns, dry season (2010) and rainy season (2011), using respectively the current profiler ADCP Doppler effect, the side-scan sonar and Van Veen sampler. In these estuaries: Açu, Cavalos and Conchas were identified the following types of bedforms: flatbed and Dunes 2-D and 3-D (small to medium size), generated at lower flow regime (Froude number <1). Structures such as ripples were observed in the Açu estuary mouth. The higher values of flow discharge and velocity were recorded in the Açu estuary (434,992 m³.s-¹ and 0,554 m.s-¹). In rainy season, despite the record of highest values of discharge and flow velocities at the mouth, the energy rates upstream did not differ much from the data of the dry season. However, in all estuaries were recorded an increase in speed and flow, with reservation to the flow in the Açu estuary and flow at the mouth of the Conchas estuary. Sediment grain sizes tend to increase towards the mouth of the estuary and these ranged from very fine sand to very coarse sand, medium sand fraction being the most recurrent. Based on the data acquired and analyzed, the estuaries Açu, Cavalos and Conchas are classified as mixed , dominated by waves and tides. According to their morphology, they are classified as estuaries constructed by bar and according to the classification by salinity, estuaries Conchas and Cavalos were ranked as hypersaline estuaries, and Açu as hypersaline and vertically well mixed type C Advisors/Committee Members: Vital, Helenice (advisor), CPF:31481981404 (advisor), http://lattes.cnpq.br/3595069999049968 (advisor).

Subjects/Keywords: Formas de fundo. Levantamento sonográfico. ADCP; Bedforms. Side scan sonar. ADCP

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Soares, C. H. C. (2012). Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . (Masters Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/18827

Chicago Manual of Style (16^th Edition):

Soares, Camila Hyslava Campos. “Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .” 2012. Masters Thesis, Universidade do Rio Grande do Norte. Accessed January 23, 2021. http://repositorio.ufrn.br/handle/123456789/18827.

MLA Handbook (7^th Edition):

Soares, Camila Hyslava Campos. “Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil .” 2012. Web. 23 Jan 2021.

Vancouver:

Soares CHC. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . [Internet] [Masters thesis]. Universidade do Rio Grande do Norte; 2012. [cited 2021 Jan 23]. Available from: http://repositorio.ufrn.br/handle/123456789/18827.

Council of Science Editors:

Soares CHC. Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil . [Masters Thesis]. Universidade do Rio Grande do Norte; 2012. Available from: http://repositorio.ufrn.br/handle/123456789/18827

6. Bryk, Alexander Bodkin. The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel.

Degree: MS, Geology, 2018, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/101039

► The interaction of flow, sediment transport, and substrate morphology (morphodynamics) leads to complex boundary configurations of ripples, dunes, and bars along alluvial rivers. The instantaneous… (more)

▼ The interaction of flow, sediment transport, and substrate morphology (morphodynamics) leads to complex boundary configurations of ripples, dunes, and bars along alluvial rivers. The instantaneous boundary morphology heavily influences the local flow structure, especially within meander bends, and the temporal evolution of these interactions determines the behavior of channels as they migrate across their floodplains. Within high-amplitude bends, large dunes often develop that have their crestlines skewed diagonally with respect to the channel boundaries. The influence of these channel-skewed bedforms on bend flow structure is poorly understood. These forms are of particular interest as they may prevent shoaling over point bars and promote erosion on the outer bank (similar to engineered bendway weirs). In addition, the geometry of these bedforms may provide nucleation points for large-scale transverse flow separation within high-amplitude bends, thus fundamentally changing the pattern of erosion and deposition within these bends. This thesis examines the primary and secondary flow structure in a high-amplitude experimental meandering channel under differing substrate conditions. Three separate substrate morphologies were tested in the Kinoshita experimental meandering channel at the Ven Te Chow Hydrosystems Laboratory. The first consisted of a flatbed condition with rectangular walls and served as a control for subsequent experiments as well as for comparison to previous studies. The second substrate included a simplified synthetic point bar and the third consisted of the synthetic point bar with added channel-skewed roughness elements. For each condition, detailed cross-sectional flow structure was measured using a Profiling Acoustic Doppler Velocimeter (PADV). Results show the strong influence of the point bar and channel-skewed roughness elements on flow structure within the Kinoshita channel. In contrast to the flatbed condition, large transverse flow separation cells were identified downstream of the bend apex in all experiments in which synthetic roughness elements were present. The zone over which the flow adjusts to bend curvature changes, known as the hydraulic transition zone (HTR), was redefined to include both the interaction of curvature-induced secondary flow cells as well as the normalized strength of secondary flow. The inclusion of secondary flow strength in the definition of the HTR demonstrates that the HTR extends farther downstream than previously thought, even under flatbed conditions. In addition, the HTR was greatly expanded when channel-skewed bedforms were present compared to both the point bar and flatbed conditions. For the point bar and bedform conditions, secondary flow strength did not lag spatially behind water surface superelevation as was observed in the flatbed case. These results have implications for bend migration and, in particular, the propensity for bends to translate versus elongate. Advisors/Committee Members: Best, James L (advisor).

Subjects/Keywords: Meandering; Flow structure; Bedforms

…sediment transport, leading to the development of roughness elements (bedforms) of… …formation and dynamics of bedforms (e.g. ripples, dunes, and bars) under various flow… …conditions (Best, 1996). Bedforms in alluvial channels may be considered a mesoscale… …see Best (2005) for a recent review of dunes). The morphodynamics of bedforms… …bedforms) that are superimposed on the point bar. Accelerating flow around a bend often…

11 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bryk, A. B. (2018). The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/101039

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bryk, Alexander Bodkin. “The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel.” 2018. Thesis, University of Illinois – Urbana-Champaign. Accessed January 23, 2021. http://hdl.handle.net/2142/101039.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bryk, Alexander Bodkin. “The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel.” 2018. Web. 23 Jan 2021.

Vancouver:

Bryk AB. The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2142/101039.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bryk AB. The influence of channel-skewed bedforms on flow structure in a high-amplitude meandering channel. [Thesis]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/101039

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Urbana-Champaign

7. Landry, Blake J. Sand bed morphodynamics under water waves and vegetated conditions.

Degree: PhD, 0106, 2011, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/24055

► The littoral zone plays an integral role in the success of today's thriving society, providing a stable food supply as well as points of trade/transport… (more)

▼ The littoral zone plays an integral role in the success of today's thriving society, providing a stable food supply as well as points of trade/transport for goods around the world. Key environmental processes in this region such as sediment transport, wave attenuation, and boundary layer development are directly governed by the presence of bathymetric features, which include large-scale sand bars upon which smaller-scale sand ripples are superimposed, as well as the presence of submarine vegetation. As a result, understanding the complex interaction among these features is imperative to determining coastline morphological changes and protecting coastal zones and society as a whole due to our strong dependence on the region. The experimental large-scale laboratory work presented herein provides new insight into the complex sediment dynamics within this region. Specifically, this study explores the impact of spatial variability in the wave envelope on bed evolution, sand ripple geometric characteristics, and migration velocities as well as effects that vegetation imparts on the sediment dynamics. Key results of the study show that it is of the utmost importance to fully resolve the wave conditions along the entire domain of a facility to understand local morphodynamics. The study reports that mild wave reflections of 20% can generate 55% variability in the small-scale bed form geometries. Analysis of high-resolution temporal and spatial bathymetry measurements shows that ripple velocities under partially progressive waves are related to the local near-bed Lagrangian mass transport velocities within the bottom boundary layer. Additional laboratory experiments with near-deeply submerged vegetated canopies (current work has a ratio of mean still water depth to plant height, Hp/hp = 7.9) using idealized vegetation (6.35-mm diameter rigid wooden cylinders) beneath standing water waves provide evidence that significant modifications in bathymetry can result without vegetation directly attenuating the surface waves. While the introduction of vegetation decreases the bar growth rate, the final equilibrium bar height can be increased due to localization of flow velocities within the intra-canopy (i.e., enhanced streaming). In vegetated conditions with high lateral density (i.e., one plant diameter on-center), bar crests formed near wave antinodes rather than under wave nodes, which is indicative of a change in the dominant mode of sediment transport from bed load to suspended load. Ultimately, the study demonstrates that bottom roughness can be controlled with the help of vegetation to provide a sustainable means of altering sediment transport, adding valuable insight to aid in coastal erosion mitigation efforts. Advisors/Committee Members: Garcia, Marcelo H. (advisor), Garcia, Marcelo H. (Committee Chair), Best, James L. (committee member), Calantoni, Joseph (committee member), Parker, Gary (committee member).

Subjects/Keywords: morphodynamics; vegetation; water waves; bathymetry; ripples; bars; bedforms; wave tank

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Landry, B. J. (2011). Sand bed morphodynamics under water waves and vegetated conditions. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/24055

Chicago Manual of Style (16^th Edition):

Landry, Blake J. “Sand bed morphodynamics under water waves and vegetated conditions.” 2011. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 23, 2021. http://hdl.handle.net/2142/24055.

MLA Handbook (7^th Edition):

Landry, Blake J. “Sand bed morphodynamics under water waves and vegetated conditions.” 2011. Web. 23 Jan 2021.

Vancouver:

Landry BJ. Sand bed morphodynamics under water waves and vegetated conditions. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2011. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2142/24055.

Council of Science Editors:

Landry BJ. Sand bed morphodynamics under water waves and vegetated conditions. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2011. Available from: http://hdl.handle.net/2142/24055

Brock University

8. Wagner, Kaleb. Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics .

Degree: Department of Earth Sciences, 2015, Brock University

URL: http://hdl.handle.net/10464/6096

► Transverse, subglacial bedforms (ribbed moraines) occur frequently in southern Keewatin, Nunavut, Canada, where they record a complex glacial history, including shifting centers of ice dispersal… (more)

Subjects/Keywords: ribbed moraines; subglacial bedforms; spatial analysis; Keewatin; deforming bed mosaic

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wagner, K. (2015). Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics . (Thesis). Brock University. Retrieved from http://hdl.handle.net/10464/6096

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wagner, Kaleb. “Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics .” 2015. Thesis, Brock University. Accessed January 23, 2021. http://hdl.handle.net/10464/6096.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wagner, Kaleb. “Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics .” 2015. Web. 23 Jan 2021.

Vancouver:

Wagner K. Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics . [Internet] [Thesis]. Brock University; 2015. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10464/6096.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wagner K. Ribbed moraines and subglacial geomorphological signatures of interior-sector palaeo-ice sheet dynamics . [Thesis]. Brock University; 2015. Available from: http://hdl.handle.net/10464/6096

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology

9. Meirelles Nunes da Rocha, S. Effects of a stratified tidal flow on the morphodynamics.

Degree: 2019, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; 10.4233/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a

► This thesis examines the effects of the stratified tidal flow on the morphodynamics of the Dutch inner shelf. The south portion of the Dutch inner… (more)

▼ This thesis examines the effects of the stratified tidal flow on the morphodynamics of the Dutch inner shelf. The south portion of the Dutch inner shelf is strongly influenced by the Rhine River ROFI (Region Of Freshwater Influence), which is generated by the discharge from the Rhine River through the Rotterdam waterways. Under stratified conditions, the three-dimensional structure of the tidal currents develops a strong cross-shore shear so that the bottom and surface currents become 180deg out of phase. The sheared flow created by stratification operates in the inner shelf and nearshore zones so that the flow asymmetries imparted by stratification are expected to impact the morphodynamics, however the role of the stratified tidal flow on the morphodynamics along the Dutch coast has been often neglected or oversimplified. In this context, this thesis aims to provide new insights on how the stratified tidal flow dictates the morphodynamics outside the surfzone. In the south portion of the Dutch coast is located the Sand Engine, a 21.5 million m3 experimental mega-nourishment that was built in 2011. This intervention created a discontinuity in the previous straight sandy coastline, altering the local hydrodynamics in a region that is influenced by the Rhine River ROFI. Estimates of the centrifugal acceleration directly after construction of the Sand Engine showed that its curved shape impacted the cross-shore flow, suggesting that the Sand Engine might have played a role in controlling the cross-shore exchange currents during the first three years after the completion of the nourishment. Presently, the curvature effects are minute owned to the morphodynamic evolution of the Sand Engine. Observations document the development of strong baroclinic-induced cross-shore exchange currents dictated by the intrusion of the river plume fronts as well as the classic tidal straining which are found to extend further into the nearshore (from 12 to 6 m depth), otherwise believed to be a mixed zone. In the inner shelf, shoaling waves are as effective in mobilizing sediment as the other co-existing flows. The influence of stratification on the hydrodynamics is translated into near-bed shear velocity in the layer immediately above the sea floor. The tide-induced bed shear stress is able to periodically agitate the bed near the peaks of flood and ebb cycles mostly during spring tides. Results from observations suggested that, under stratified conditions, relatively high values of bed shear stress are sustained for a prolonged period of time. The results also revealed that the non-tidal flow, such as the wind-induced flow, plays a role in controlling the bed mobility. However, wave-induced bed shear stress in general does not set sediment in motion during fair weather conditions and thus the stirring role of the waves is mostly important during storms. The co-exiting near-bed flows in the inner shelf are responsible for moulding the seafloor so that the resulting types of bedforms can reveal important… Advisors/Committee Members: Stive, M.J.F., Reniers, A.J.H.M., Pietrzak, J.D., Delft University of Technology.

Subjects/Keywords: stratification; bedforms; sediment transport

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APA (6^th Edition):

Meirelles Nunes da Rocha, S. (2019). Effects of a stratified tidal flow on the morphodynamics. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; 10.4233/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a

Chicago Manual of Style (16^th Edition):

Meirelles Nunes da Rocha, S. “Effects of a stratified tidal flow on the morphodynamics.” 2019. Doctoral Dissertation, Delft University of Technology. Accessed January 23, 2021. http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; 10.4233/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a.

MLA Handbook (7^th Edition):

Meirelles Nunes da Rocha, S. “Effects of a stratified tidal flow on the morphodynamics.” 2019. Web. 23 Jan 2021.

Vancouver:

Meirelles Nunes da Rocha S. Effects of a stratified tidal flow on the morphodynamics. [Internet] [Doctoral dissertation]. Delft University of Technology; 2019. [cited 2021 Jan 23]. Available from: http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; 10.4233/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a.

Council of Science Editors:

Meirelles Nunes da Rocha S. Effects of a stratified tidal flow on the morphodynamics. [Doctoral Dissertation]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; 10.4233/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; urn:NBN:nl:ui:24-uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a ; http://resolver.tudelft.nl/uuid:b98e7799-c0d3-42ca-8c9c-70ee64bf059a

10. Baker, Meg. The role of clay minerals in the dynamics and deposits of sediment gravity flows.

Degree: PhD, 2020, Bangor University

URL: https://research.bangor.ac.uk/portal/en/theses/the-role-of-clay-minerals-in-the-dynamics-and-deposits-of-sediment-gravity-flows(0e14cdf5-dbb7-403b-843b-f86926fa22f6).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801332

► Understanding cohesive, clay-laden subaqueous sediment gravity flows is vital, because clay is one of the most abundant sediment types on Earth and sediment gravity flows… (more)

▼ Understanding cohesive, clay-laden subaqueous sediment gravity flows is vital, because clay is one of the most abundant sediment types on Earth and sediment gravity flows transport large volumes of this sediment into the ocean. Previous cohesive sediment gravity flow studies have overlooked the distinct cohesive strengths of different types of clay mineral. To isolate the effect of clay mineral type, lock-exchange experiments contrasted sediment gravity flows composed of weakly cohesive kaolinite clay, strongly cohesive bentonite clay, and non-cohesive silica flour at a wide range of volume concentrations. For high-density sediment gravity flows of the same concentration, kaolinite flows had a higher maximum head velocity and a longer runout distance than bentonite flows, because the bentonite flows were able to form a stronger network of particle bonds of greater rheological strength. Frictional forces reduced the mobility of the silica-flour flows at high concentrations. Dimensional analysis shows that the yield stress of the suspension can be used to predict the runout distance and the dimensionless head velocity of the sediment gravity flows, independent of the clay type. Clay mineral type within natural, cohesive, high-density sediment gravity flows is expected to control their runout distance and the geometry of their deposits. A metadata analysis was conducted to determine if the cohesive strength of different clay minerals left a signature in the geometry of modern, mud-rich submarine fans. For the fans studied, the normalised vertical-fan-growth-rate increased for fans dominated by kaolinite via illite to smectite, suggesting fans containing strongly cohesive clays may cover a smaller area and be thicker. The dominant clay mineral in the fans also appeared to have a latitudinal control, because the weathering intensity on adjacent continents controls clay mineral formation. These results suggest the relationships between latitude, clay mineral assemblage and the geometry of modern, mud-rich submarine fans should be further explored. In the natural environment, cohesive sediment gravity flows are commonly composed of mixtures of clay minerals. Lock-exchange experiments produced sediment gravity flows carrying mixtures of bentonite and kaolinite at a fixed 20% volumetric concentration. Above bentonite proportions of 20%, further increasing the bentonite proportion increases the yield stress of the starting suspension and reduces the head velocity and runout distance of the flows. However, the mixture containing 10% bentonite had a lower yield stress and was more mobile than the pure kaolinite flow, suggesting that the small amount of bentonite reduced the cohesive strength of the suspension. In contrast, for pure-bentonite, high-density sediment gravity flows, increasing the volume concentration by adding 25% sand increases the yield stress of the suspension and reduces the runout distance and the velocity of the flows. This demonstrates that non-cohesive particles can contribute to the cohesive properties of…

Subjects/Keywords: Clay; Sediment gravity flow; Cohesion; Bedforms; Flume experiments; Submarine fan; Sedimentology

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APA (6^th Edition):

Baker, M. (2020). The role of clay minerals in the dynamics and deposits of sediment gravity flows. (Doctoral Dissertation). Bangor University. Retrieved from https://research.bangor.ac.uk/portal/en/theses/the-role-of-clay-minerals-in-the-dynamics-and-deposits-of-sediment-gravity-flows(0e14cdf5-dbb7-403b-843b-f86926fa22f6).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801332

Chicago Manual of Style (16^th Edition):

Baker, Meg. “The role of clay minerals in the dynamics and deposits of sediment gravity flows.” 2020. Doctoral Dissertation, Bangor University. Accessed January 23, 2021. https://research.bangor.ac.uk/portal/en/theses/the-role-of-clay-minerals-in-the-dynamics-and-deposits-of-sediment-gravity-flows(0e14cdf5-dbb7-403b-843b-f86926fa22f6).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801332.

MLA Handbook (7^th Edition):

Baker, Meg. “The role of clay minerals in the dynamics and deposits of sediment gravity flows.” 2020. Web. 23 Jan 2021.

Vancouver:

Baker M. The role of clay minerals in the dynamics and deposits of sediment gravity flows. [Internet] [Doctoral dissertation]. Bangor University; 2020. [cited 2021 Jan 23]. Available from: https://research.bangor.ac.uk/portal/en/theses/the-role-of-clay-minerals-in-the-dynamics-and-deposits-of-sediment-gravity-flows(0e14cdf5-dbb7-403b-843b-f86926fa22f6).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801332.

Council of Science Editors:

Baker M. The role of clay minerals in the dynamics and deposits of sediment gravity flows. [Doctoral Dissertation]. Bangor University; 2020. Available from: https://research.bangor.ac.uk/portal/en/theses/the-role-of-clay-minerals-in-the-dynamics-and-deposits-of-sediment-gravity-flows(0e14cdf5-dbb7-403b-843b-f86926fa22f6).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801332

11. Mazières, Alaïs. Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf.

Degree: Docteur es, Sédimentologie marine et paléoclimats, 2014, Bordeaux

URL: http://www.theses.fr/2014BORD0171

►

Ce travail présente une analyse de l'évolution morphologique et des processus sédimentaires actuels du plateau continental interne sud-aquitain, (sud-est du Golfe de Gascogne, France),secteur riche… (more)

▼

Ce travail présente une analyse de l'évolution morphologique et des processus sédimentaires actuels du plateau continental interne sud-aquitain, (sud-est du Golfe de Gascogne, France),secteur riche en données, mais sur lequel de nombreuses questions restent néanmoins en suspens. Il s'articule autour de deux zones ateliers complémentaires : la zone de « La Salie-Biscarrosse » sur le plateau continental interne sud-aquitain au sud des passes du Bassin d'Arcachon (entre 5 et 50 m de profondeur d’eau), et la tête du canyon de Capbreton et ses abords (entre 5 et 120 m de profondeur d’eau). Deux approches sont utilisées : (1) une approche descriptive et comparative (dans le temps), utilisant des données géo-acoustiques(sondeur multi faisceaux, sonar latéral et sondeur de sédiments), des prélèvements et (2) une approche mettant en oeuvre des modélisations numériques des interactions houles / courants /sédiments. Les résultats obtenus sur le plateau interne aquitain ont permis d'améliorer la connaissance de la morphologie, de la nature et de la géométrie interne des corps sédimentaires, d'étudier leur évolution au cours des 29 dernières années (entre 1984 et 2013)et de proposer des facteurs à l’origine de cette évolution. Le résultat majeur est la mise en évidence de « sorted bebforms » entretenus par la houle; dont la surprenante migration vers le nord-est est à associer à la récente découverte d'intenses épisodes de « poleward current » sur le plateau. Le suivi entre 1998 et 2013 de l’évolution morphologique de la tête du Canyon de Capbreton, située à seulement 250 m du littoral montre une évolution rapide qui fluctue cependant autour d'une position d'équilibre. Par ailleurs l’influence de la dérive littorale sur les transferts de sédiments du plateau vers le canyon a pu être démontrée. En-effet, les arguments morphologiques et sédimentaires, associés à la modélisation numérique, prouvent que la dérive littorale aquitaine alimente épisodiquement (conditions de houle forte) la tête de canyon en sables littoraux.

This study proposes an analysis of the morphological evolution and recent sedimentary processes of the south Aquitaine inner shelf (south east Bay of Biscay, France). This area is greatly documented but improvement of our knowledge is needed for a better understanding.Two complementary study areas are analyzed: « La Salie-Biscarrosse » area of the south-Aquitaine inner shelf (in a water depth extending from 5 to 50 m), and the head of the Capbreton Canyon (in a water depth extending from 5 to 120 m). Two approaches are used:(1) a descriptive and comparative analysis of the geophysical and sedimentological data setsand (2) a numerical modeling taking into account swell, current and sediments. The results obtained allow the description and the interpretation of the morphology, the nature, the internal geometry of the sedimentary structures, and their evolution along the last 29 years(between 1984 and 2013). The major result highlights the presence of sorted bedforms maintained by the swell, migrating northeastward…

Advisors/Committee Members: Mulder, Thierry (thesis director), Gillet, Hervé (thesis director).

Subjects/Keywords: Plateau aquitain interne; Canyon de Capbreton; Dérive littorale; Sorted bedforms; Suivi temporel; Aquitaine inner shelf,; Capbreton canyon; Littoral drift; Sorted bedforms; Time lapse survey

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APA (6^th Edition):

Mazières, A. (2014). Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2014BORD0171

Chicago Manual of Style (16^th Edition):

Mazières, Alaïs. “Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf.” 2014. Doctoral Dissertation, Bordeaux. Accessed January 23, 2021. http://www.theses.fr/2014BORD0171.

MLA Handbook (7^th Edition):

Mazières, Alaïs. “Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf.” 2014. Web. 23 Jan 2021.

Vancouver:

Mazières A. Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf. [Internet] [Doctoral dissertation]. Bordeaux; 2014. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2014BORD0171.

Council of Science Editors:

Mazières A. Evolution morphologique et processus sédimentaires actuels du plateau continental interne sud-aquitain : étude comparée des zones de la Salie-Biscarosse (Sud des passes d'Arcachon) et la zone de la tête du canyon de Capbreton. : Morphological evolution and current sedimentary processes of the south Aquitain inner- shelf. [Doctoral Dissertation]. Bordeaux; 2014. Available from: http://www.theses.fr/2014BORD0171

Universiteit Utrecht

12. Vellinga, A.J. Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach.

Degree: 2014, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/301315

► Both open-channel flows and density currents are able to create supercritical-flow bedforms. The morphodynamics of these supercritical-flow bedforms are, however, still poorly understood. This is… (more)

Subjects/Keywords: morphodynamic; supercritical; flow; bedform; bedforms; cyclic step; cyclic steps; RANS; depth-resolved; numerical; model

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APA (6^th Edition):

Vellinga, A. J. (2014). Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/301315

Chicago Manual of Style (16^th Edition):

Vellinga, A J. “Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach.” 2014. Masters Thesis, Universiteit Utrecht. Accessed January 23, 2021. http://dspace.library.uu.nl:8080/handle/1874/301315.

MLA Handbook (7^th Edition):

Vellinga, A J. “Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach.” 2014. Web. 23 Jan 2021.

Vancouver:

Vellinga AJ. Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach. [Internet] [Masters thesis]. Universiteit Utrecht; 2014. [cited 2021 Jan 23]. Available from: http://dspace.library.uu.nl:8080/handle/1874/301315.

Council of Science Editors:

Vellinga AJ. Morphodynamics of bedforms in a supercritical-flow regime: a depth-resolved numerical modelling approach. [Masters Thesis]. Universiteit Utrecht; 2014. Available from: http://dspace.library.uu.nl:8080/handle/1874/301315

Dalhousie University

13. Hare, Jenna. OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES.

Degree: MS, Department of Oceanography, 2013, Dalhousie University

URL: http://hdl.handle.net/10222/31138

► The spatial and temporal structure of the flow, vorticity and stress over equilibrium orbital-scale sand ripples are investigated at turbulence-resolving scales with a wide-band coherent… (more)

Subjects/Keywords: Physical oceanography; Nearshore processes; Bedforms; Oscillatory bottom boundary layers; Bottom shear stress; Coherent Doppler; Turbulence

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APA (6^th Edition):

Hare, J. (2013). OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/31138

Chicago Manual of Style (16^th Edition):

Hare, Jenna. “OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES.” 2013. Masters Thesis, Dalhousie University. Accessed January 23, 2021. http://hdl.handle.net/10222/31138.

MLA Handbook (7^th Edition):

Hare, Jenna. “OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES.” 2013. Web. 23 Jan 2021.

Vancouver:

Hare J. OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES. [Internet] [Masters thesis]. Dalhousie University; 2013. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10222/31138.

Council of Science Editors:

Hare J. OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES. [Masters Thesis]. Dalhousie University; 2013. Available from: http://hdl.handle.net/10222/31138

14. Schrijvershof, R.A. Bedform morphology under combined wave-current conditions in a nearshore environment.

Degree: 2015, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/311427

► The shape and geometry of bedforms in the nearshore zone strongly controls the turbulence and flow field above them, and as such, they determine the… (more)

▼ The shape and geometry of bedforms in the nearshore zone strongly controls the turbulence and flow field above them, and as such, they determine the vertical sand concentration profile and with that the magnitude and direction of sediment transport. Understanding the relations between forcing and resultant bathymetry is therefore of crucial importance for coastal modelling purposes. The relationship between forcing and bedforms is, however, less understood for bedforms that are formed under the combined action of waves and currents (combined flows) than for pure waves or currents. To give insight in to the effect of a dynamic nearshore environment on combined flow bedform geometry, I studied the effect of changing hydrodynamics (within and between tidal cycles) on bedform morphology. Thereby, the accuracy of existing bedform geometry predictors is tested. A one-month measuring campaign was conducted at the beach of Egmond aan Zee to measure hydrodynamics together with small-scale sea-bed bathymetry, using a three-dimensional sonar ripple profiler (3DSRPLS). The sonar-acquired bathymetry images are processed in to Digital Elevation Models (DEMs) and classified in to four different bed states: small-scale 2D ripples, small-scale 3D ripples, large-scale bedforms, and super-positioned bedforms. Results show that a θc – θw bed state stability diagram gives a good segregation of small-scale 2D ripples and large-scale bedforms, that small-scale 3D ripples are stable across a large range of the current strength, and that large-scale bedforms are formed under equal wave and current strengths. Tidal development of hydrodynamics and bedforms shows that bedform height shows a distinct post-high tide arrested development when large scale bedforms develop. This causes a decoupling of forcing and morphology, which is the reason that (a part of) the bedforms are not in equilibrium with the flow. I discuss that this out-of-equilibrium state is the main reason for the dis-ability of the equilibrium predictors to accurately predict bedform geometry. Therefore, future research on nearshore intertidal environments should specifically pay attention to hysteresis effects and its consequence for predicting geometry. Advisors/Committee Members: Ruessink, B.G., Kleinhans, M.G..

Subjects/Keywords: Bedforms; nearshore; combined flow; hysteresis

…bedforms were predominantly aligned with the waves, and migrated primarily in the direction of… …be discussed next. 4 Morphology Describing the morphology of bedforms in an objective… …produced by waves in the nearshore are symmetric ripples. The bedforms develop in a consistent… …property of ripples not discussed so far. The small-scale bedforms are assigned 2D for wave… …be sufficient to describe the bedforms (Figure 4A). A super imposed increasing…

11 more images…

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APA (6^th Edition):

Schrijvershof, R. A. (2015). Bedform morphology under combined wave-current conditions in a nearshore environment. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/311427

Chicago Manual of Style (16^th Edition):

Schrijvershof, R A. “Bedform morphology under combined wave-current conditions in a nearshore environment.” 2015. Masters Thesis, Universiteit Utrecht. Accessed January 23, 2021. http://dspace.library.uu.nl:8080/handle/1874/311427.

MLA Handbook (7^th Edition):

Schrijvershof, R A. “Bedform morphology under combined wave-current conditions in a nearshore environment.” 2015. Web. 23 Jan 2021.

Vancouver:

Schrijvershof RA. Bedform morphology under combined wave-current conditions in a nearshore environment. [Internet] [Masters thesis]. Universiteit Utrecht; 2015. [cited 2021 Jan 23]. Available from: http://dspace.library.uu.nl:8080/handle/1874/311427.

Council of Science Editors:

Schrijvershof RA. Bedform morphology under combined wave-current conditions in a nearshore environment. [Masters Thesis]. Universiteit Utrecht; 2015. Available from: http://dspace.library.uu.nl:8080/handle/1874/311427

University of Plymouth

15. Thorpe, Antony. Sediment transport and bedform dynamics in rip currents.

Degree: PhD, 2016, University of Plymouth

URL: http://hdl.handle.net/10026.1/6558

► Simultaneous in-situ measurements of waves, currents, water depth, suspended sediment concentrations and bed profiles were made in a rip channel on Perranporth Beach, Cornwall, UK.… (more)

▼ Simultaneous in-situ measurements of waves, currents, water depth, suspended sediment concentrations and bed profiles were made in a rip channel on Perranporth Beach, Cornwall, UK. Perranporth is a high energy beach (annual offshore Hs = 1.6 m) which is macro-tidal (mean spring range = 6.3 m) and the grain size is medium sand (D50 = 0.28 – 0.34 mm). It can be classified as a low tide bar – rip beach and exhibits a relatively flat inter-tidal zone with pronounced rhythmic low tide bar - rip morphology. Data were collected over two field campaigns, totalling 14 tidal cycles and including 27 occurrences of rip currents, in a range of offshore wave heights (Hs = 0.5 – 3 m). The in-situ measurements were supplemented with morphological beach surveys. Sediment samples were taken for grain size analysis. The rip current was found to be tidally modulated. The strongest rip flow (0.7 m/s) occurred at mid to low tide, when waves were breaking on the adjacent bar. Rip flow persisted when the bar had dried out at the lowest tidal elevations. The rip was observed to pulse at a very low frequency (VLF) with a period of 15 - 20 minutes, which was shown to be influenced by wave breaking on the adjacent bar. The rip was completely in-active at high tide. Bedforms were ubiquitous in the rip channel and occurred at all stages of the tide. Visual observations found bedforms to be orientated shore parallel. When the rip was active, mean bedform length and height was 1.45 m and 0.06 m respectively. The size and position of the bedforms in the nearshore suggested that they were best classified as megaripples. When the rip was not active, the mean bedform length and height was 1.09 m and 0.06 m respectively. In rip conditions, with typical mean offshore flow rates of > 0.3 m/s, the bedforms migrated in an offshore direction at a mean rate of 0.16 cm/min and a maximum rate of 4.6 cm/min. The associated mean bedform sediment transport rate was 0.0020 kg/m/s, with a maximum rate of 0.054 kg/m/s. In the rip, migration rates were correlated with offshore directed mean flow strength. In non-rip conditions, bedform migration was onshore directed with a mean rate of 0.09 cm/min and a maximum rate of = 2.2 cm/min. The associated mean bedform transport rate was 0.0015 kg/m/s, with a maximum rate of = 0.041 kg/m/s. The onshore bedform transport was correlated with incident wave skewness, and was weakly correlated with orbital velocity. Over a tidal cycle, the offshore directed bedform transport was only marginally larger in rip currents than when it was when onshore directed in non-rip conditions. Sediment suspension in the rip current was shown to be dependent on the presence of waves. Suspended sediment transport was dominated by the mean flux. The mean flux contributed > 70% of total suspended transport on 19 out of the 27 observed rip current occurrences. The net contribution of the oscillatory flux was small compared to the mean flux. Within the oscillatory component, a frequency domain partitioning routine showed that the VLF motion was an…

Subjects/Keywords: 551.46; Rip current; Sediment Transport; Bedforms; Megaripples; high energy; macro tidal; VLF; Suspended sediment transport

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APA (6^th Edition):

Thorpe, A. (2016). Sediment transport and bedform dynamics in rip currents. (Doctoral Dissertation). University of Plymouth. Retrieved from http://hdl.handle.net/10026.1/6558

Chicago Manual of Style (16^th Edition):

Thorpe, Antony. “Sediment transport and bedform dynamics in rip currents.” 2016. Doctoral Dissertation, University of Plymouth. Accessed January 23, 2021. http://hdl.handle.net/10026.1/6558.

MLA Handbook (7^th Edition):

Thorpe, Antony. “Sediment transport and bedform dynamics in rip currents.” 2016. Web. 23 Jan 2021.

Vancouver:

Thorpe A. Sediment transport and bedform dynamics in rip currents. [Internet] [Doctoral dissertation]. University of Plymouth; 2016. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10026.1/6558.

Council of Science Editors:

Thorpe A. Sediment transport and bedform dynamics in rip currents. [Doctoral Dissertation]. University of Plymouth; 2016. Available from: http://hdl.handle.net/10026.1/6558

Colorado School of Mines

16. Ono, Kenya. Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills.

Degree: PhD, Geology and Geological Engineering, 2017, Colorado School of Mines

URL: http://hdl.handle.net/11124/170670

► This dissertation focuses on the southern California active margin continental slopes, and tests the hypothesis that deepwater slope architectures on active continental margins differ from… (more)

▼ This dissertation focuses on the southern California active margin continental slopes, and tests the hypothesis that deepwater slope architectures on active continental margins differ from passive margins or foreland basins due to both the structurally-controlled steep gradients, and the narrowness of the shelf platform. These controlling factors allow the high-gradient hinterland to connect directly to the steep deepwater slope and are insusceptible to relative sea-level change. This high-gradient hinterland to deepwater slope margin causes the direct and sustained sediment supply from the river to the continental slope. To test this hypothesis, two main study regions were chosen in the Eocene forearc deepwater basins filled with the Great Valley Sequence Belt, which are the La Jolla Group, exposed north of San Diego, and the Juncal Formation in Frazier Park. Field work in these two regions allowed for a comparison between two types of deepwater slope systems. The La Jolla Group is composed of relatively lower aspect ratio channel complexes, which form a prograding upper slope. The Juncal Formation is composed of relatively higher-aspect ratio channel complexes, which form an intra-slope fan complex with a feeder channel on the middle slope. Both systems are highly channelized, as was hypothesized to be characteristic for active margins. The La Jolla prograding channel complexes demonstrate a highly channelized upper slope environment with considerably lower slope progradation rate, as compared to passive margins or foreland basins. The Juncal slope fan complex demonstrates that the majority of the fan volume is formed by avulsive channel complexes without lobe elements. The channel fills inboth systems span from heterolithic fine-grained channel fills, to sandy to heterolithic channel fill, and sandy fills with basal conglomerates. All the channel fills indicate an abundance of bypass signatures. This is especially remarkable for the heterolithic channel fills, which are different from the existing models for fine-grained channel fills that consider channel abandonment or passive infill. Furthermore, all channel fills are interpreted to be dominated by Froude supercritical flow deposits due to pervasive scour-and-fill structures with backsets. This suggests that the Froude supercritical flow may control the observed highly irregular shape and distribution of the sandstones (e.g., mounded shape and mosaic-like facies distribution) in the channel fills. The studied channel complexes provide an outcrop analog for modern sea-floor upslope migrating scour and fill structures that form crescent-shape bedforms in channels and submarine canyons. This work and the comparison to modern systems suggest that supercritical flow and bypassing turbidity currents are significant processes on active continental margins due to both high sediment supply, and the steep hinterland to continental margin slopes. Advisors/Committee Members: Plink-Björklund, Piret (advisor), Benson, Robert D. (committee member), Anderson, Donna S. (committee member), Carr, Mary (committee member), Dykstra, Mason (committee member).

Subjects/Keywords: backsets; deepwater; scour-and-fill structures; channel; active margin continental slope; Froude supercritical flow bedforms

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ono, K. (2017). Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170670

Chicago Manual of Style (16^th Edition):

Ono, Kenya. “Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills.” 2017. Doctoral Dissertation, Colorado School of Mines. Accessed January 23, 2021. http://hdl.handle.net/11124/170670.

MLA Handbook (7^th Edition):

Ono, Kenya. “Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills.” 2017. Web. 23 Jan 2021.

Vancouver:

Ono K. Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2017. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/11124/170670.

Council of Science Editors:

Ono K. Deepwater slope channels on active continental margins, Eocene forearc basin, California: architecture and Froude supercritical flow channel fills. [Doctoral Dissertation]. Colorado School of Mines; 2017. Available from: http://hdl.handle.net/11124/170670

17. Doré, Arnaud. Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes.

Degree: Docteur es, Physique de l'environnement, 2015, Bordeaux

URL: http://www.theses.fr/2015BORD0379

►

Les dunes de sable sont des formes très présentes en milieu marin. Comprendre l'évolution des dunes est un enjeu important pour prévoir les caractéristiques de… (more)

▼

Les dunes de sable sont des formes très présentes en milieu marin. Comprendre l'évolution des dunes est un enjeu important pour prévoir les caractéristiques de l'écoulement, les flux sédimentaires, et les variations de la bathymétrie. Les dunes sous-marines représentent un risque pour les activités humaines, a fortiori avec l'intérêt croissant pour les énergies marines renouvelables, pour la navigation, ou l'industrie offshore. Bien que la connaissance des dunes représente un intérêt scientifique et opérationnel de premier ordre, les processus physiques conduisant leur évolution sont toujours mal compris. En outre, la prévision de leurs caractéristiques géométriques et de leur dynamique basée essentiellement sur des formules empiriques reste peu précise. Dans ce travail de thèse, un modèle numérique est d'abord utilisée pour modéliser les dunes soumises à un écoulement stationnaire. Les simulations reproduisent l'évolution d'un fond faiblement perturbé jusqu'à un champ de dunes en équilibre avec l'écoulement et apportent des connaissances approfondies sur les processus physiques mis en jeu. Ensuite, les résultats d'un ensemble de campagnes de mesures réalisées dans la passe sud du bassin d'Arcachon permettent d'étudier la dynamique des dunes tidales in situ et relier leur asymétrie et leur migration aux résiduels de transport sédimentaire. Enfin, l'application du modèle numérique avec les conditions de forçages extraites des campagnes de mesures permet de reproduire la dynamique des dunes tidales ainsi que la génération de rides d'un ordre de grandeur comparable aux rides surimposées observées in situ. Ces résultats ouvrent des perspectives intéressantes en vue du développement d'un modèle opérationnel de prévision de la dynamique des dunes tidales.

Sand dunes are ubiquitous beforms in nature within subaqueous environments. Understanding dune evolution is important issue to accurately predict the ow circulation, sediment uxes and bathymetric variations in sandy subaqueous environments. Sand dunes may pose a significant risk for offshore activities in coastal environments, especially with the growing development of renewable marine energy, for navigation or the offshore industry. Although sand dunes represent a great scientific and operational interest, their evolution is still poorly understood due to their complex behavior. The aim of the thesis work was to study the physical processes driving the evolution of subaqueous sand dunes and to understand their in situ dynamics within tidal environments. First, a numerical model was employed to simulate sand dunes under stationary current conditions. The simulations reproduced the morphodynamic evolution of a slightly perturbed bed until a steady sand dune field in equilibrium with the ow. The results offered a deeper understanding of the physical processes driving the bed evolution to equilibrium. Second, an array of in situ measurements was carried out into the Arcachon inlet, in southwest France, to study the dynamics of tidal sand dunes. For the first time their…

Advisors/Committee Members: Bonneton, Philippe (thesis director), Garlan, Thierry (thesis director).

Subjects/Keywords: Dunes; Rides; Évolution morphodynamique; Processus physiques; Formes surimposées; Dunes; Ripples; Morphodynamic evolution; Physical processes; Superimposed bedforms

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APA (6^th Edition):

Doré, A. (2015). Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2015BORD0379

Chicago Manual of Style (16^th Edition):

Doré, Arnaud. “Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes.” 2015. Doctoral Dissertation, Bordeaux. Accessed January 23, 2021. http://www.theses.fr/2015BORD0379.

MLA Handbook (7^th Edition):

Doré, Arnaud. “Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes.” 2015. Web. 23 Jan 2021.

Vancouver:

Doré A. Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes. [Internet] [Doctoral dissertation]. Bordeaux; 2015. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2015BORD0379.

Council of Science Editors:

Doré A. Modélisation de l'évolution morphodynamique des dunes sous-marines : Modelling of the morphodynamic evolution of submarine sand dunes. [Doctoral Dissertation]. Bordeaux; 2015. Available from: http://www.theses.fr/2015BORD0379

University of Aberdeen

18. Pugh, Jonathan Michael. The Quaternary desert sediments of the Al Liwa area, Abu Dhabi.

Degree: PhD, 1997, University of Aberdeen

URL: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152865050005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362250

► Once the characteristics of the study area have been defined within the context of desert environments the theory of sediment accumulation in such a setting… (more)

▼ Once the characteristics of the study area have been defined within the context of desert environments the theory of sediment accumulation in such a setting will be critically reviewed. The processes and products of aeolian sand transport and deposition that dominate the region will be discussed in Chapter Four and illustrated with contemporary examples from the study area and ancient equivalents from the Permian-age Clipper Field of the Southern North Sea. Once the primary building blocks of aeolian bedforms have been considered, the relationship between aeolian bedforms and the wind will be addressed in Chapter Five. The basis for the classification of aeolian bedforms on the grounds of morphology and morphometry will be examined, as will the possible controls on bedform size and spacing and the concept of draas as equilibrium bedforms. The apparent relationships that exist between bedform morphology, alignment and wind regime in a number of the world's desert areas will be critically considered in this section. The concepts of bounding surfaces, bedform accumulation and preservation will be considered in Chapter Six. The roles of sand supply and subsidence will be addressed, as will the significance of interdune sequences. Once the factors controlling the evolution, distribution, and the accumulation of aeolian sediments in aeolian bedforms have been considered, the dynamics of sand-sea systems and the significance of regional bounding surfaces will be critically assessed in Chapter Seven. In Chapter Eight the application of ground penetrating radar (GPR) as a means to determine the internal sturcutre of modern aeolian bedforms will be considered in conjunction with the results of a survey conducted on the Al Liwa area. The theories and principles discussed to date will then be applied to the study area. In Chapter Nine observed patterns of present-day dune morphology and morphometry across the region will be described in detail and the question of bedform morphology and alignment with respect to the contemporary wind regime addressed.

Subjects/Keywords: 551; Sand-sea systems; Aeolian bedforms; Wind

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APA (6^th Edition):

Pugh, J. M. (1997). The Quaternary desert sediments of the Al Liwa area, Abu Dhabi. (Doctoral Dissertation). University of Aberdeen. Retrieved from https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152865050005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362250

Chicago Manual of Style (16^th Edition):

Pugh, Jonathan Michael. “The Quaternary desert sediments of the Al Liwa area, Abu Dhabi.” 1997. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2021. https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152865050005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362250.

MLA Handbook (7^th Edition):

Pugh, Jonathan Michael. “The Quaternary desert sediments of the Al Liwa area, Abu Dhabi.” 1997. Web. 23 Jan 2021.

Vancouver:

Pugh JM. The Quaternary desert sediments of the Al Liwa area, Abu Dhabi. [Internet] [Doctoral dissertation]. University of Aberdeen; 1997. [cited 2021 Jan 23]. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152865050005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362250.

Council of Science Editors:

Pugh JM. The Quaternary desert sediments of the Al Liwa area, Abu Dhabi. [Doctoral Dissertation]. University of Aberdeen; 1997. Available from: https://eu03.alma.exlibrisgroup.com/view/delivery/44ABE_INST/12152865050005941 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362250

University of Illinois – Urbana-Champaign

19. Perillo, Mauricio. Flow, sediment transport and bedforms under combined flows.

Degree: PhD, 1655, 2013, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/44484

► Combined flow, which refers to a combination of unidirectional and wave-induced oscillatory flows, is omnipresent in natural environments and generates a range of bedforms on… (more)

▼ Combined flow, which refers to a combination of unidirectional and wave-induced oscillatory flows, is omnipresent in natural environments and generates a range of bedforms on sandy beds. Combined-flow bedforms are abundant in coastal and lacustrine environments, as well as in their ancient counterparts in the rock record. However, few experimental studies have focused on the relationship between the morphology and formative hydraulic conditions of combined-flow bedforms. There is thus a wide range of unexplored stability conditions for such bedforms, especially with intermediate oscillation periods. The aim of this research is to undertake new experimental work in the Large Oscillatory Water-Sediment Tunnel (LOWST) in order to address this gap in knowledge. The LOWST has a test section 12.5 m long, 0.8 m wide and 1.2 m high, with the oscillatory motion generated by three pistons. Unidirectional currents were superimposed on these water oscillations using two centrifugal pumps. Fifty-five experiments were conducted in the LOWST, both with and without an initially flattened bed. Bedform development in a 0.25 mm diameter sand bed was studied under pure oscillatory and combined flow conditions with oscillation periods of 4, 5 and 6 s. The maximum orbital velocity (Uo) was varied from 0.10 to 0.70 m/s while the unidirectional component (Uu) was varied from 0 to 0.50 m/s. This thesis presents new experimental data on bedform initiation and development under unidirectional, oscillatory and, more extensively, under combined flows. In particular, this study was able to populate zones of the Terra incognita region previously defined in the literature (Southard, 1991). In this thesis, the stable bedform configurations under a diverse range of flow conditions were studied and divided into no motion (NM), 2D symmetric ripples (SR), 3D symmetric ripples (SR), 3D symmetric dunes (SR), 3D asymmetric ripples (AR), 3D quasi-asymmetric ripples (QAR), 3D asymmetric dunes (AD), 3D current ripples (CR), 3D current dunes (CD) and upper-stage plane bed (USPB). Each of these bedform stages was described, characterized and reproduced in dimensional and dimensionless phase diagrams. A complete re-evaluation of the nomenclature for combined flow bedforms is proposed, which includes their planform and the cross-sectional geometries in order to better represent the bed morphologies. This new nomenclature was carefully selected in order to integrate the bedform studies both in the unidirectional and oscillatory literature. One of the main changes that allows the integration with the nomenclature used in unidirectional flows is the reclassification of large ripples as dunes. Furthermore, the introduction of the planform and cross-sectional geometries as properties to classify bedforms leads to the definition of a stable phase space for two-dimensional symmetrical ripples and three-dimensional quasi-asymmetrical ripples. Furthermore, the experimental data collected under unidirectional flows larger than 0.30 m/s allows expansion of the current… Advisors/Committee Members: Best, James L. (advisor), Best, James L. (Committee Chair), Garcia, Marcelo H. (committee member), Parker, Gary (committee member), Baas, Jaco H. (committee member).

Subjects/Keywords: Bedforms; Combined Flows; Wave-Current Interactions; Phase diagrams; rippes; dunes; bed morphology; bedform development; bedform genesis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Perillo, M. (2013). Flow, sediment transport and bedforms under combined flows. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/44484

Chicago Manual of Style (16^th Edition):

Perillo, Mauricio. “Flow, sediment transport and bedforms under combined flows.” 2013. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 23, 2021. http://hdl.handle.net/2142/44484.

MLA Handbook (7^th Edition):

Perillo, Mauricio. “Flow, sediment transport and bedforms under combined flows.” 2013. Web. 23 Jan 2021.

Vancouver:

Perillo M. Flow, sediment transport and bedforms under combined flows. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2013. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2142/44484.

Council of Science Editors:

Perillo M. Flow, sediment transport and bedforms under combined flows. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2013. Available from: http://hdl.handle.net/2142/44484

University of Waterloo

20. Plumb, Benjamin. Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers.

Degree: 2017, University of Waterloo

URL: http://hdl.handle.net/10012/12164

► Urbanization is known to change the hydrologic and sediment supply regimes of rivers, causing more frequent, flashier flood events (hydromodification) and a reduction and redistribution… (more)

▼ Urbanization is known to change the hydrologic and sediment supply regimes of rivers, causing more frequent, flashier flood events (hydromodification) and a reduction and redistribution of sediment sources. Presently, the impact that these changes have on bedload transport in gravel-bed channels and the resulting impact on bed morphology remains largely unknown due to a lack of process based studies. A better understanding of how riverbed form and processes evolve with urbanization is critical as they are a primary factor in controlling stream stability, providing habitat for aquatic species and influencing flood elevations. Additionally, stream rehabilitation is becoming increasingly common in urban rivers and an understanding of how sediment transport dynamics change with the alterations common to urbanization is critical for a successful design. This thesis explores the impact of urbanization, which is the combination of hydromodification and alterations to sediment supply, on the morphodynamics (linkages between channel form and process) of bedforms in gravel-bed rivers. Specific objectives are: 1) to determine if detectable differences in bed morphology exist between rural and urban rivers in the same hydrophysiographic region; 2) to characterize the sediment transport dynamics of a highly urbanized channel; 3) to investigate the differences in geomorphically significant flows and sediment transport characteristics for different levels of watershed urbanization; and 4) to generalize field specific results using a mobile-bed laboratory flume to investigate the sediment transport characteristics for different levels of watershed hydromodification. Longitudinal profiles of 11 rural and 9 urban watercourses with pool-riffle dominated morphologies in the same hydrophysiographic region (Southern Ontario, Canada) were investigated using three objective bedform identification methods; zero-crossing analysis, bedform differencing technique and residual pool depth analysis, as well as visual field identification. Results indicate that urban rivers possess deeper pools and a more topographically variable bed. A field investigation was undertaken to characterize event-based sediment transport dynamics of a highly urbanized gravel-bed river over a three year period. Mimico Creek, located in Toronto, Ontario, Canada, is nearly fully urbanized and lacks significant stormwater management controls, therefore making it a representative study reach. Bedload transport was measured using both active and passive sampling methods to characterize the mobility and transport dynamics of the entire range of surface particles. During this time, over 10 floods were sampled ranging from the approximate threshold discharge to well over the bankfull discharge. Coarse particle mobility differed from that previously reported in literature for rivers with more natural flow regimes. A strong link was found between coarse particle mobility and the transport dynamics of finer material which tends to dominate the bedload. …

Subjects/Keywords: urbanization; hydromodification; gravel-bed; bedforms; pool-riffle; fluvial geomorphology; sediment transport; geomorphic work; unsteady flow; bedload hysteresis; river rehabilitation

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APA (6^th Edition):

Plumb, B. (2017). Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/12164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Plumb, Benjamin. “Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers.” 2017. Thesis, University of Waterloo. Accessed January 23, 2021. http://hdl.handle.net/10012/12164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Plumb, Benjamin. “Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers.” 2017. Web. 23 Jan 2021.

Vancouver:

Plumb B. Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10012/12164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Plumb B. Impacts of Hydromodification and Sediment Supply Alterations on Bedload Transport and Bed Morphology in Urbanizing Gravel-bed Rivers. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/12164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of South Carolina

21. Nelson, Timothy Robert. Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence.

Degree: PhD, Earth and Ocean Sciences, 2013, University of South Carolina

URL: https://scholarcommons.sc.edu/etd/2313

► Bedform roughness, caused by ripples on the seabed, plays an important role in controlling sediment dynamics in the nearshore region. In this dissertation, the… (more)

▼ Bedform roughness, caused by ripples on the seabed, plays an important role in controlling sediment dynamics in the nearshore region. In this dissertation, the temporal and spatial evolution of ripples from two field sites located in the South Atlantic Bight, offshore Long Bay, SC and Georgia are used to relate wave-induced ripple geometry (wavelength and orientation) to near bed directional wave velocities. 2-D spectral analysis techniques were developed to automate detection of ripple wavelength, direction, and irregularity. This analysis showed that magnitude, direction, and duration of wave forcing controls ripple geometry and irregularity. During highly energetic events, ripple geometry changes rapidly and the ripples align with the main wave direction. During periods of low energy conditions, close to the critical conditions for initiation of sediment motion, ripple evolution occurs at a much slower rate often leading to irregularities such as terminations and bifurcations along the ripple crest. Under constantly changing wave direction, the rippled bed becomes highly disorganized. Equilibrium ripples were found to occur only when either strong wave forcing was present or the forcing remained constant for a long duration. These equilibrium ripples, when combined to a database of existing published ripple measurements, were found to have a wavelength that scales with the wave orbital semi-excursion and sediment grain diameter. Ripple steepness was found to remain relatively constant and it only slightly increased for shorter ripple wavelengths. These findings allowed for the development of a new equilibrium ripple predictor suitable for application in a wide range of wave and sediment conditions. In order to describe the temporal variability between equilibrium states, a 2-D time-variable ripple prediction model developed. This new model allowed for the prediction of ripple wavelength, height, and orientation. Since ripple irregularity is associated with directionality, the new model also predicts the irregularity of the rippled seabed and second order ripples (i.e. cross-ripples). This model was tested against existing time-dependent models and found to improve predictions of wavelength, height, and orientation, especially for relict ripples. Turbulence was measured via the eddy correlation and inertial dissipation methods from which drag coefficients were calculated. The data reveal a trend of decreasing drag for increasing ripple irregularity and increasing ripple height. In similar fashion, suspended sediment concentrations were calculated from ABS systems and it was found that convective sediment resuspension extended to greater elevation above the seabed when ripples were more regular. Advisors/Committee Members: George Voulgaris.

Subjects/Keywords: Earth Sciences; Geology; Physical Sciences and Mathematics; Bedforms; Equilibrium Ripples; Relict Ripples; Suspended Sediment; Time Dependent Ripple Model; Turbulence

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APA (6^th Edition):

Nelson, T. R. (2013). Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence. (Doctoral Dissertation). University of South Carolina. Retrieved from https://scholarcommons.sc.edu/etd/2313

Chicago Manual of Style (16^th Edition):

Nelson, Timothy Robert. “Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence.” 2013. Doctoral Dissertation, University of South Carolina. Accessed January 23, 2021. https://scholarcommons.sc.edu/etd/2313.

MLA Handbook (7^th Edition):

Nelson, Timothy Robert. “Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence.” 2013. Web. 23 Jan 2021.

Vancouver:

Nelson TR. Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence. [Internet] [Doctoral dissertation]. University of South Carolina; 2013. [cited 2021 Jan 23]. Available from: https://scholarcommons.sc.edu/etd/2313.

Council of Science Editors:

Nelson TR. Benthic Boundary Layer Processes: Bedform Evolution and Bottom Turbulence. [Doctoral Dissertation]. University of South Carolina; 2013. Available from: https://scholarcommons.sc.edu/etd/2313

University of South Carolina

22. Arrington, Tanner. Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina.

Degree: MS, Geography, 2013, University of South Carolina

URL: https://scholarcommons.sc.edu/etd/1273

► Field data was collected systematically to characterize the geomorphic variations in a river transition from the southern Blue Ridge to the Piedmont physiographic regions… (more)

▼ Field data was collected systematically to characterize the geomorphic variations in a river transition from the southern Blue Ridge to the Piedmont physiographic regions in South Carolina. Ten study reaches were surveyed for cross-sections and longitudinal profiles. Surface grid samples of bed material collected. Downstream hydraulic geometry and downstream fining of bed material were analyzed using traditional power functions and exponential decay relationships. Reach-scale channel bed morphology (bedforms) was analyzed under the assumption that the transition in bedforms is related to changes in hydraulic geometry and sediment characteristics. Well-developed downstream trends of hydraulic geometry variables (width, depth and velocity) and bed material fining were observed. However, variations within the general trends reflect the influence of a key transition zone characterized by substantial tributary inputs, drastic decreases in slope, and the presence of erosion-resistant bedrock knickpoints. Bedforms were distinguished using a regime diagram, an approach that utilizes hydraulic and sediment data that is independent of drainage area. Plots of relative grain submergence (R/D84), relative form submergence (R/H), Darcy-Weisbach friction factor (f) and slope vs. area reveal trends in the data that are not discernible with downstream models. Hydraulic, sediment, and bedform data suggest that structurally controlled breaks in slope are influential to bedform characteristics, resulting in forced morphologies that may not be distinguished using simple downstream models. This corroborates the utility of scale-independent methods, especially in mountain or transitional environments where fluvial controls may be longitudinally forced and sporadic. These results have implications for river management and restoration approaches in such environments, as scale-independent models and landscape-scale perspectives can be beneficial to management objectives. Advisors/Committee Members: Allan James.

Subjects/Keywords: Geography; Social and Behavioral Sciences; Bedforms; Downstream Hydraulic Geometry; Geomorphology; Mountain Rivers; Regime Diagram; River Restoration

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APA (6^th Edition):

Arrington, T. (2013). Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina. (Masters Thesis). University of South Carolina. Retrieved from https://scholarcommons.sc.edu/etd/1273

Chicago Manual of Style (16^th Edition):

Arrington, Tanner. “Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina.” 2013. Masters Thesis, University of South Carolina. Accessed January 23, 2021. https://scholarcommons.sc.edu/etd/1273.

MLA Handbook (7^th Edition):

Arrington, Tanner. “Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina.” 2013. Web. 23 Jan 2021.

Vancouver:

Arrington T. Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina. [Internet] [Masters thesis]. University of South Carolina; 2013. [cited 2021 Jan 23]. Available from: https://scholarcommons.sc.edu/etd/1273.

Council of Science Editors:

Arrington T. Geomorphic Variation of A Transitional River: Blue Ridge to Piedmont, South Carolina. [Masters Thesis]. University of South Carolina; 2013. Available from: https://scholarcommons.sc.edu/etd/1273

Utah State University

23. Goodridge, Wade H. Sediment Transport Impacts Upon Culvert Hydraulics.

Degree: PhD, Civil and Environmental Engineering, 2009, Utah State University

URL: https://digitalcommons.usu.edu/etd/416

► Sedimentation buildup and accumulation can cause serious impediments to the hydraulic capacity of culvert systems. There has not been any significant research to date… (more)

▼ Sedimentation buildup and accumulation can cause serious impediments to the hydraulic capacity of culvert systems. There has not been any significant research to date regarding the behavior of bed load transport nor the implications of bed forms upon the hydraulics associated with culvert flow. The primary objective of this study was to investigate how sediment transport occurs in a culvert and to then develop a methodology and test setup to successfully investigate this sediment transport. The investigation was limited to studying culvert and pipeline transport of alluvial material in sand and gravel sizes. This dissertation develops a semi-empirical bed load transport equation from existing open channel flow models to be used in predicting sediment yields in culvert applications. Incipient motion and critical shear stresses were investigated for application into eight empirically based models. The methods analyzed include the Meyer-Peter Müller, Engelund and Hansen, Shields, Toffaleti (as seen in the United States Army Corps of Engineers program HEC RAS), Schoklitsch, DuBoy, Yang, and Rottner methods. These methods were tested for predictive accuracy to physically modeled bed load transport data obtained from a 304.8 mm (11.89 in) diameter culvert. Tests involved fully pressurized, partially pressurized inlet controlled, and open channel flow regimes for a variety of bed elevations and bedforms. Bedform regime and associated resistance impacts on flow energy were presented to better understand their hydraulic consequence in culvert applications. An extensive literature review regarding sediment transport in both open channel and closed conduit applications is provided to develop a foundation of knowledge to pursue further research in this area. This literature review summarizes the current body of scientific knowledge that is applicable to sediment transport in culverts. Investigations into both historical and current works are cited throughout this studies literature review. A tested methodology is presented for the investigation of sediment bed load transport in culvert applications. Development of a procedure for the testing of critical shear limits and bed load transport is outlined. A detailed application example is provided. Recommended changes in testing techniques and physical model are made for the next generation of culvert sediment transport research. Advisors/Committee Members: William J. Rahmeyer, Blake P. Tullis, Michael C. Johnson, ;.

Subjects/Keywords: Bedforms; Culverts; Hydraulics; Incipient Motion; Sediment Trasport; Civil Engineering

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APA (6^th Edition):

Goodridge, W. H. (2009). Sediment Transport Impacts Upon Culvert Hydraulics. (Doctoral Dissertation). Utah State University. Retrieved from https://digitalcommons.usu.edu/etd/416

Chicago Manual of Style (16^th Edition):

Goodridge, Wade H. “Sediment Transport Impacts Upon Culvert Hydraulics.” 2009. Doctoral Dissertation, Utah State University. Accessed January 23, 2021. https://digitalcommons.usu.edu/etd/416.

MLA Handbook (7^th Edition):

Goodridge, Wade H. “Sediment Transport Impacts Upon Culvert Hydraulics.” 2009. Web. 23 Jan 2021.

Vancouver:

Goodridge WH. Sediment Transport Impacts Upon Culvert Hydraulics. [Internet] [Doctoral dissertation]. Utah State University; 2009. [cited 2021 Jan 23]. Available from: https://digitalcommons.usu.edu/etd/416.

Council of Science Editors:

Goodridge WH. Sediment Transport Impacts Upon Culvert Hydraulics. [Doctoral Dissertation]. Utah State University; 2009. Available from: https://digitalcommons.usu.edu/etd/416

University of Texas – Austin

24. Eastwood, Erin Nancy. Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes.

Degree: PhD, Geological Sciences, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/25791

► This dissertation combines studies of aeolian bedforms and aeolian dune-field patterns to create a comprehensive set of tools that can be used in tandem (or… (more)

Subjects/Keywords: Aeolian; Sediment transport; Dune-field evolution; Dune-field development; Paleoclimate reconstructions; White Sands Dune Field, NM; Permian Cedar Mesa Sandstone, Utah; Numerical modeling; Sediment supply; Transport capacity; Dune-field patterns; Clustered bedforms; Superimposed bedforms; Climate change; Landscape evolution; Wind regimes

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APA (6^th Edition):

Eastwood, E. N. (2011). Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/25791

Chicago Manual of Style (16^th Edition):

Eastwood, Erin Nancy. “Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes.” 2011. Doctoral Dissertation, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/25791.

MLA Handbook (7^th Edition):

Eastwood, Erin Nancy. “Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes.” 2011. Web. 23 Jan 2021.

Vancouver:

Eastwood EN. Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2011. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/25791.

Council of Science Editors:

Eastwood EN. Reconstructing environmental forcings on aeolian dune fields : results from modern, ancient, and numerically-simulated dunes. [Doctoral Dissertation]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/25791

Texas A&M University

25. Bean, Daniel Andrew. Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico.

Degree: PhD, Oceanography, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1007

► Using a high-resolution deep-towed seismic system, we have discovered a series of contour-current bedforms at the base of the Sigsbee Escarpment in the Bryant Canyon… (more)

▼ Using a high-resolution deep-towed seismic system, we have discovered a series of contour-current bedforms at the base of the Sigsbee Escarpment in the Bryant Canyon region of the northern Gulf of Mexico. We identify a continuum of bedforms that include furrows, meandering furrows, flutes and fully eroded seafloor. These contourcurrent bedforms are linked to current velocities ranging from 20 to upwards of 60 cm/s based on nearby current meter measurements and similar flume generated bedforms (Allen, 1969). We identify erosion and non-deposition of up to 25 meters of surface sediment at the base of Sigsbee Escarpment. Using 3-D and high-resolution seismic data, sediment samples, and submersible observations from the Green Knoll area, we further define contour-current bedforms along the Sigsbee Escarpment. The study area is divided into eleven zones based on bedform morphology, distribution, and formation processes. We identify a contourcurrent bedform continuum similar to that of the Bryant Canyon region, while the data reveals additional features that result from the interaction between topography and contour-currents. Three regional seismic marker horizons are identified, and we establish an age of ~19 kyr on the deepest horizon. The seismic horizons are correlated with very subtle changes in sediment properties, which in turn define the maximum depth of erosion for each of the individual bedforms. Finally, we show for the first time that furrowed horizons can be acoustically imaged in three dimensions below seafloor. Analysis of imagery of several horizons obtained from 3-D seismic data from the Green Knoll region establishes the existence of multiple paleo-furrow events. The contour current pattern preserved by the paleofurrows is similar to the presently active seafloor furrows. And, based on the morphology and development that we establish for the active seafloor furrows, we show that paleo-furrows are likely formed by currents that are in the same range as those measured today (20-60 cm/s), that erode into sediments with similar physical properties to the fine-grained hemipelagic sediments of the present-day seafloor. We further suggest the possibility that furrows are formed during inter-glacial highstands and buried during glacial lowstands. Advisors/Committee Members: Bryant, William R. (advisor), Slowey, Niall C. (advisor), Gardner, Wilford D. (committee member), Hilde, Thomas W. C. (committee member), Scott, Erik D. (committee member).

Subjects/Keywords: furrows; contour-current bedforms; Sigsbee Escarpment; Gulf of Mexico; paleo-furrows

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APA (6^th Edition):

Bean, D. A. (2009). Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1007

Chicago Manual of Style (16^th Edition):

Bean, Daniel Andrew. “Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico.” 2009. Doctoral Dissertation, Texas A&M University. Accessed January 23, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1007.

MLA Handbook (7^th Edition):

Bean, Daniel Andrew. “Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico.” 2009. Web. 23 Jan 2021.

Vancouver:

Bean DA. Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1007.

Council of Science Editors:

Bean DA. Past and present deepwater contour-current bedforms at the base of the Sigsbee Escarpment, northern Gulf of Mexico. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1007

26. Weij, D. (author). The interaction between bed-load transport and dune orientation.

Degree: 2012, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:25fb62d2-51a7-4afe-a932-1dc8204b424c

► Bedforms play an important role in the sediment transport of a river. Because of their importance many experiments have been carried out to better understand… (more)

▼ Bedforms play an important role in the sediment transport of a river. Because of their importance many experiments have been carried out to better understand bedforms. Most experiments concern transverse bedforms (with crests aligned perpendicular to the flow direction). However, bathymetry measurements show many instances of oblique dunes. Oblique bedforms induce flow and sediment transport in the transverse direction. Based on the flume experiments of Talmon [2009], Sieben & Talmon [2011] proposed formulae to determine the bed-load transport direction over oblique dunes. To apply these formulae the dune orientation has to be known. Therefore, Sieben & Talmon [2011] proposed to derive the dune angle by relating it to the relative dune migration rate along the dune crest. This was applied in the preliminary work of Weij [2012]. It was found that the current formulae give unrealistic results. The main objective of this thesis is to improve the prediction of dune orientation angle for large-scale modelling. The mechanisms involved in the formation of oblique dunes are investigated in a simplified environment. For the simplified environment we created a model based on the model created by Jerolmack & Mohrig [2005]. The model calculates the bed level change in one-dimensional slices, which are then coupled with transverse sediment transport to create a quasi 2D model. The results of show a dune orientation that eventually finds an equilibrium. Two explanations were given: (1) A gradient in transverse sediment transport can decrease or increase the dune migration rate, (2) Dune crests break up, and merge before reaching a larger angle. Based on these findings, the calculation of the dune angle is adapted in three ways: (1) The effect of transverse sediment transport on migration rate, (2) a reduced dune height for larger angles, (3) a limited dune orientation angle. The first measure is promising; it reduces the calculated dune orientation angles to more realistic values. However, the current implementation is problematic. The second measure is simple to implement and also reduces the dune orientation angle to more realistic values. However, the factor used to reduce the dune height has no physical basis. The third measure did not lead to satisfying results, but can be combined with the other measures. In the simplified environment cross-stream sediment transport was based on just the transverse slope. However, the flume experiments by Talmon [2009] show that sediment transport also depends largely on the changed flow pattern near the bed. We analysed the flume experiments carried out by Talmon [2009]. These experiments were carried out to quantify the transverse sediment transport over oblique dunes. Furthermore, we carried out detailed three-dimensional flow simulations. We used the detailed model of Nabi [2012] to carry out these flow simulations. Sieben & Talmon [2011] derived formulae for the mean sediment transport direction based on the experiments of Talmon [2009]. During our analysis of the flume experiments and… Advisors/Committee Members: Uijttewaal, W.S.J. (mentor), Mosselman, E. (mentor), Sloff, C.J. (mentor), Talmon, A.M. (mentor).

Subjects/Keywords: dunes; bedforms; bed-load transport; dune orientation; numerical modelling

…1.1.1 Oblique Bedforms . . . . . . 1.1.2 Flow over Oblique Bedforms 1.1.3 Definitions… …Chapter 1 Introduction 1.1 1.1.1 Background Oblique Bedforms Dunes are one of the main… …bedforms found in rivers. Dunes are large sand waves with a mostly triangular shape. They have a… …Bathymetry of the Waal between kilometre 947 and 949 1.1.2 Flow over Oblique Bedforms Talmon… …height of the bedforms stays equal. Because shear stress is higher at the crest of the bedform…

10 more images…

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APA (6^th Edition):

Weij, D. (. (2012). The interaction between bed-load transport and dune orientation. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:25fb62d2-51a7-4afe-a932-1dc8204b424c

Chicago Manual of Style (16^th Edition):

Weij, D (author). “The interaction between bed-load transport and dune orientation.” 2012. Masters Thesis, Delft University of Technology. Accessed January 23, 2021. http://resolver.tudelft.nl/uuid:25fb62d2-51a7-4afe-a932-1dc8204b424c.

MLA Handbook (7^th Edition):

Weij, D (author). “The interaction between bed-load transport and dune orientation.” 2012. Web. 23 Jan 2021.

Vancouver:

Weij D(. The interaction between bed-load transport and dune orientation. [Internet] [Masters thesis]. Delft University of Technology; 2012. [cited 2021 Jan 23]. Available from: http://resolver.tudelft.nl/uuid:25fb62d2-51a7-4afe-a932-1dc8204b424c.

Council of Science Editors:

Weij D(. The interaction between bed-load transport and dune orientation. [Masters Thesis]. Delft University of Technology; 2012. Available from: http://resolver.tudelft.nl/uuid:25fb62d2-51a7-4afe-a932-1dc8204b424c

University of Waikato

27. Brannigan, Adrian Mark. Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system .

Degree: 2009, University of Waikato

URL: http://hdl.handle.net/10289/2799

► Historical change in the geomorphology, hydrodynamics, and surficial sediment of the tidal delta system of Tauranga Harbour are investigated with the general aim of analysing… (more)

▼ Historical change in the geomorphology, hydrodynamics, and surficial sediment of the tidal delta system of Tauranga Harbour are investigated with the general aim of analysing The general aims of this thesis are: firstly to analyse historical changes to inlet delta system geomorphology using historical hydrographic charts, secondly, to conduct hydrodynamic numerical modelling using historical bathymetries to access changes in peak spring flow and potential net tidal sediment transport, and thirdly, to analyse historical changes in surficial sediment and bedforms. Geomorphic change was investigated through plotting difference in bathymetry graphs and conducting cross sections taken from digisitied bathymetries obtained from historical hydrographic charts from 1852, 1879, 1901, 1927, 1954 and a modern bathymetry from 2006. Two-dimensional hydrodynamic numerical modelling was conducted to investigate the changes in peak tidal current flow and potential net sediment transport between 1852 and 2006. Changes in surficial sediment patterns were determined through completing a side scan sonar survey with associated sediment samples for ground truthing of grain size and underwater videography to gather surficial shell coverage information. This was used to produce a surficial sediment coverage map which was compared to historical studies Major geomorphological findings include that the shipping channel appears to have induced minor change in the geomorphology of the FTD but such changes are similar to those identified in the historical bathymetries of 1852, 1879, 1901, 1927, 1954 prior to dredging. Significant changes have occurred on the ETD, with the majority of the ETD showing scour of 1 m while the terminal lobe has extended seawards. This is associated with historical (since 1852) narrowing of the inlet from Panepane Point to Mt Maunganui by ~ 900 m. Hydrodynamic numerical modelling has shown a significant increase in potential net tidal sediment transport in the Cutter Channel due to dredging, while the Maunganui Roads Channel shows a reduction of net potential tidal sediment transport that is associated with the dredging of this channel. The area surrounding Panepane Point undergoes significant increases and decreases in net potential tidal sediment transport both before and after dredging Investigation of the surficial sediment patterns over the FTD and ETD from sidescan sonar and bottom samples show that between 1983 and 2007 there has been a northwards extension of the area of major shell (greater than 50 %) converge in the main ebb channel as well as reduction in major shell converge in flood tidal delta ebb shield region. The Maunganui Roads Channel changes from sitly sands to medium and fine sands.

Subjects/Keywords: Residual Distance Plot; Van Veen Grab Sampler; Bedforms; Accretion; Depostion; Sediment Transport Pathways

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APA (6^th Edition):

Brannigan, A. M. (2009). Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system . (Masters Thesis). University of Waikato. Retrieved from http://hdl.handle.net/10289/2799

Chicago Manual of Style (16^th Edition):

Brannigan, Adrian Mark. “Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system .” 2009. Masters Thesis, University of Waikato. Accessed January 23, 2021. http://hdl.handle.net/10289/2799.

MLA Handbook (7^th Edition):

Brannigan, Adrian Mark. “Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system .” 2009. Web. 23 Jan 2021.

Vancouver:

Brannigan AM. Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system . [Internet] [Masters thesis]. University of Waikato; 2009. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10289/2799.

Council of Science Editors:

Brannigan AM. Change in geomorphology, hydrodynamics and surficial sediment of the Tauranga entrance tidal delta system . [Masters Thesis]. University of Waikato; 2009. Available from: http://hdl.handle.net/10289/2799

Arizona State University

28. Pendleton-Hoffer, Mary C. Wind-driven Modification of Small Bedforms in Gusev Crater, Mars.

Degree: Geological Sciences, 2016, Arizona State University

URL: http://repository.asu.edu/items/40328

Subjects/Keywords: Geology; Planetology; Geomorphology; aeolian; bedforms; dust devil tracks; Mars; sand

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APA (6^th Edition):

Pendleton-Hoffer, M. C. (2016). Wind-driven Modification of Small Bedforms in Gusev Crater, Mars. (Masters Thesis). Arizona State University. Retrieved from http://repository.asu.edu/items/40328

Chicago Manual of Style (16^th Edition):

Pendleton-Hoffer, Mary C. “Wind-driven Modification of Small Bedforms in Gusev Crater, Mars.” 2016. Masters Thesis, Arizona State University. Accessed January 23, 2021. http://repository.asu.edu/items/40328.

MLA Handbook (7^th Edition):

Pendleton-Hoffer, Mary C. “Wind-driven Modification of Small Bedforms in Gusev Crater, Mars.” 2016. Web. 23 Jan 2021.

Vancouver:

Pendleton-Hoffer MC. Wind-driven Modification of Small Bedforms in Gusev Crater, Mars. [Internet] [Masters thesis]. Arizona State University; 2016. [cited 2021 Jan 23]. Available from: http://repository.asu.edu/items/40328.

Council of Science Editors:

Pendleton-Hoffer MC. Wind-driven Modification of Small Bedforms in Gusev Crater, Mars. [Masters Thesis]. Arizona State University; 2016. Available from: http://repository.asu.edu/items/40328

Arizona State University

29. Leary, Kate. Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers.

Degree: Geological Sciences, 2018, Arizona State University

URL: http://repository.asu.edu/items/50429

Subjects/Keywords: Geomorphology; bedforms; bedload transport; fluid dynamics; fluvial systems; repeat multibeam sonar; sediment transport

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APA (6^th Edition):

Leary, K. (2018). Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers. (Doctoral Dissertation). Arizona State University. Retrieved from http://repository.asu.edu/items/50429

Chicago Manual of Style (16^th Edition):

Leary, Kate. “Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers.” 2018. Doctoral Dissertation, Arizona State University. Accessed January 23, 2021. http://repository.asu.edu/items/50429.

MLA Handbook (7^th Edition):

Leary, Kate. “Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers.” 2018. Web. 23 Jan 2021.

Vancouver:

Leary K. Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers. [Internet] [Doctoral dissertation]. Arizona State University; 2018. [cited 2021 Jan 23]. Available from: http://repository.asu.edu/items/50429.

Council of Science Editors:

Leary K. Field and Flume Investigations of Bedload Transport and Bedforms in Sand-Bedded Rivers. [Doctoral Dissertation]. Arizona State University; 2018. Available from: http://repository.asu.edu/items/50429

30. Swanson, Travis Eric. Bedform interaction and preservation.

Degree: PhD, Geological Sciences, 2015, University of Texas – Austin

URL: http://hdl.handle.net/2152/32633

► The shape and motion of bedforms are envisioned to arise as a consequence of a hierarchical cascade of interactions that occur within a bedform field.… (more)

▼ The shape and motion of bedforms are envisioned to arise as a consequence of a hierarchical cascade of interactions that occur within a bedform field. Interactions within the field are driven by conditions external to the bedform field, called boundary conditions. One such boundary condition is transport regime, the annual cycle of sediment transporting winds that drive uneven movement and deformation of bedforms. Paradoxically, uneven bedform movement results in geometric organization, as bedform crests align to wind regime. High resolution mapping of bedform crest movement reveals stochastic crest motion that acts to maintain the geometric organization of the bedform field. Stochastic motion of bedforms is driven by the interaction of bedform topography with sediment transporting flows. One such interaction occurs when oblique bedform crests create a wake containing trailing helical vortices. Each trailing helical vortex may preferentially route sediment to or away from a downstream bedform. This routing causes deformation or ablation of the downstream bedform. Either way, a section of the downstream bedform may deform to an oblique orientation. The oblique section may also trail a helical wake and further propagate stochastic bedform motion downstream. Bedform field boundary conditions provide an external influence on stochastic bedform motion. A numerical model of dynamic bedform topography is fueled by four sets of boundary conditions: a uni-modal and bi-modal wind regime each investigated with and without the restriction of a linear bedform source area. The chosen boundary conditions are demonstrated to influence the shape and stochastic motion of bedforms within the field the rate at which the bedforms grow and mature. Fields of bedforms, driven by boundary conditions may leave a stratigraphic record of their stochastic motion. Given sufficient time, boundary conditions are transient. A numerical experiment is performed to investigate the preservation of signals from both stochastic dune motion and a transient boundary condition, the strengthening and weakening of sediment transport with time. The numerical experiment demonstrates that stochastic dune motion and transient boundary conditions influence the preservation of bedform topography in the resulting stratigraphic record. Advisors/Committee Members: Mohrig, David (advisor), Kocurek, Gary (advisor).

Subjects/Keywords: Bedforms; Ripples; Dunes; Surface processes; Cross-strata; Aeolian

…51 3.3.1 The geometric configuration of spur-bearing bedforms .............51 viii… …vortices to bedform interactions......54 3.3.2.3 Growth of spur-bearing bedforms in a flume… …Image North Loup bedforms and crest traces ...................................46 Figure 3.3… …Figure 3.9: The transition between 2D and 3D bedforms ...................................58… …Figure 3.10: Deformation of 3D bedforms…

11 more images…

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APA (6^th Edition):

Swanson, T. E. (2015). Bedform interaction and preservation. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/32633

Chicago Manual of Style (16^th Edition):

Swanson, Travis Eric. “Bedform interaction and preservation.” 2015. Doctoral Dissertation, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/32633.

MLA Handbook (7^th Edition):

Swanson, Travis Eric. “Bedform interaction and preservation.” 2015. Web. 23 Jan 2021.

Vancouver:

Swanson TE. Bedform interaction and preservation. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2015. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/32633.

Council of Science Editors:

Swanson TE. Bedform interaction and preservation. [Doctoral Dissertation]. University of Texas – Austin; 2015. Available from: http://hdl.handle.net/2152/32633

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Open Access Theses and Dissertations