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M Stone - One of the best experts on this subject based on the ideXlab platform.
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in channel surficial Fine Grained Sediment laminae part i physical characteristics and formational processes
Hydrological Processes, 1994Co-Authors: Ian G Droppo, M StoneAbstract:An in-channel surficial depositional feature (surficial Fine-Grained laminae) composed of loosely bound Fine Sediment deposited during low flow conditions has often been observed in river systems in south-western Ontario. The physical characteristics of this feature have been determined by a direct observation image analysis system. This Sediment consists primarily of flocculated Fine-Grained material. The size distributions of surficial Fine-Grained laminae and suspended Sediment were not significantly different. Each distribution is bimodal in nature and shows a characteristic grain size deficiency in the 4-5 μm size range. This observation suggests that flocculation and not low discharge or low competence is the dominant mechanism for the formation of surficial Fine-Grained laminae under conditions of low flow in fluvial systems of south-western Ontario. A quantitative assessment of this feature shows its potential importance as a source of Fine-Grained Sediment and associated contaminants for downstream transport.
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in channel surficial Fine Grained Sediment laminae part ii chemical characteristics and implications for contaminant transport in fluvial systems
Hydrological Processes, 1994Co-Authors: M Stone, Ian G DroppoAbstract:Samples of surficial Fine-Grained laminae (SFGL) were collected in three south-western Ontario rivers. Each Sediment sample was subjected to a sequential extraction procedure designed to partition particulate metals (Cd, Pb, Cu, Zn) into five operationally deFined fractions: (1) exchangeable; (2) bound to carbonates; (3) bound to Fe-Mn oxides; (4) bound to organic matter; and (5) residual. Particulate phosphus was sequentially extracted from the Sediment samples into three fractions: (1) non-apatite inorganic P; (2) apatite P; and (3) organic P. The major accumulate phases of trace metals in SFGL are carbonates, Fe-Mn oxides and organic matter. The content of NAIP in SFGL ranged from 17 to 38% of total particulate P. Compared with suspended and bed Sediments, levels of P and trace metals in SFGL were lower at the study sites. A conceptual overview of physical, chemical and biological processes influencing formation of SFGL and the potential role of this Fine-Grained Sediment for contaminant transport in fluvial systems is presented.
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geochemical composition phosphorus speciation and mass transport of Fine Grained Sediment in two lake erie tributaries
Hydrobiologia, 1993Co-Authors: M Stone, M C EnglishAbstract:The concentration of major elements (Si, Al, Ca, Mg, Na, K, Fe, Ti, Mn and P), particulate phosphorus forms (NH4Cl-RP, BD-RP, NaOH-RP, HCl-RP and NaOH(85)-RP) and carbon content were determined in six size fractions (<8, 8–12, 12–19, 19–31, 31–42 and 42–<60 μm) of Sediment collected at gauging stations located in two Lake Erie tributaries (Big Creek and Big Otter Creek). Concentrations of major elements and phosphorus forms were remarkably similar in Sediment size fractions from both rivers. Nonapatite inorganic P (NAIP) and organic P (OP) concentrations increased with decreasing grain size while apatite inorganic P (AIP) content decreased with decreasing grain size. Results of phosphorus fractionation studies were combined with historical (particle size) and hydrometric data to simulate the export of particle P on tributary Sediment <63 μm. AIP represents 67 and 70% of the calculated particulate P mass while NAIP accounts for 26 and 23% of Sediment-bound P transported in Big Otter Creek and Big Creek, respectively. The <8 μm size fraction of tributary Sediment is the most significant for the potential release of bioavailable P into the water column.
María Gómez Ballesteros - One of the best experts on this subject based on the ideXlab platform.
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Morphobathymetric analysis of the large Fine-Grained Sediment waves over the Gulf of Valencia continental slope (NW Mediterranean)
Geomorphology, 2016Co-Authors: Marta Ribó, Pere Puig, Araceli Muñoz, Claudio Lo Iacono, Pere Masqué, Albert Palanques, Juan Acosta, Jorge Guillén, María Gómez BallesterosAbstract:Abstract Detailed analysis of recently acquired swath bathymetry, together with high-resolution seismic profiles and bottom Sediment samples, revealed the presence of large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope. As many other deep-water Sediment waves, these features were previously attributed to gravitational slope failure, related to creep-like deformation, and are here reinterpreted as Sediment wave fields extending from 250 m depth to the continental rise, at ~ 850 m depth. Geometric parameters were computed from the high-resolution multibeam dataset. Sediment wave lengths range between 500 and 1000 m, and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to minimum values of 2 m high. Sediment waves on the lower part of the slope are quasi-stationary vertically accreting, whereas they show an upslope migrating pattern from the mid-slope to the upper part of the continental slope. High-resolution seismic profiles show continuous internal reflectors, with Sediment waves merging down-section and Sediment wave packages decreasing in thickness downslope. These Sediment packages are thicker on the crest of each individual Sediment wave and thinner on the downslope flank. 210Pb analyses conducted on Sediment cores collected over the Sediment wave fields also indicate slightly higher Sediment accumulation rates on the wave crests. Sediment wave formation processes have been inferred from contemporary hydrodynamic observations, which reveal the presence of near-inertial internal waves interacting with the Gulf of Valencia continental slope. Internal wave activity is suggested to be the preferential mechanism for the transport and deposition of Sediment, and the maintenance of the observed Sediment wave fields.
Ian G Droppo - One of the best experts on this subject based on the ideXlab platform.
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in channel surficial Fine Grained Sediment laminae part i physical characteristics and formational processes
Hydrological Processes, 1994Co-Authors: Ian G Droppo, M StoneAbstract:An in-channel surficial depositional feature (surficial Fine-Grained laminae) composed of loosely bound Fine Sediment deposited during low flow conditions has often been observed in river systems in south-western Ontario. The physical characteristics of this feature have been determined by a direct observation image analysis system. This Sediment consists primarily of flocculated Fine-Grained material. The size distributions of surficial Fine-Grained laminae and suspended Sediment were not significantly different. Each distribution is bimodal in nature and shows a characteristic grain size deficiency in the 4-5 μm size range. This observation suggests that flocculation and not low discharge or low competence is the dominant mechanism for the formation of surficial Fine-Grained laminae under conditions of low flow in fluvial systems of south-western Ontario. A quantitative assessment of this feature shows its potential importance as a source of Fine-Grained Sediment and associated contaminants for downstream transport.
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in channel surficial Fine Grained Sediment laminae part ii chemical characteristics and implications for contaminant transport in fluvial systems
Hydrological Processes, 1994Co-Authors: M Stone, Ian G DroppoAbstract:Samples of surficial Fine-Grained laminae (SFGL) were collected in three south-western Ontario rivers. Each Sediment sample was subjected to a sequential extraction procedure designed to partition particulate metals (Cd, Pb, Cu, Zn) into five operationally deFined fractions: (1) exchangeable; (2) bound to carbonates; (3) bound to Fe-Mn oxides; (4) bound to organic matter; and (5) residual. Particulate phosphus was sequentially extracted from the Sediment samples into three fractions: (1) non-apatite inorganic P; (2) apatite P; and (3) organic P. The major accumulate phases of trace metals in SFGL are carbonates, Fe-Mn oxides and organic matter. The content of NAIP in SFGL ranged from 17 to 38% of total particulate P. Compared with suspended and bed Sediments, levels of P and trace metals in SFGL were lower at the study sites. A conceptual overview of physical, chemical and biological processes influencing formation of SFGL and the potential role of this Fine-Grained Sediment for contaminant transport in fluvial systems is presented.
Albert Palanques - One of the best experts on this subject based on the ideXlab platform.
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Large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope (NW Mediterranean)
Atlas of Bedforms in the Western Mediterranean, 2016Co-Authors: Marta Ribó, Pere Puig, Araceli Muñoz, Claudio Lo Iacono, Pere Masqué, Albert Palanques, Juan Acosta, Jorge Guillén, María Gomez-ballesterosAbstract:Recently acquired swath bathymetry, high-resolution seismic profiles and bottom Sediment samples have revealed the presence of large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope. Like many other deep-water Sediment waves, these features were previously attributed to gravitational slope failure related to creep-like deformation, and have now been reinterpreted as Sediment wave fields extending from 250 m depth to the continental rise at ~850 m depth. Sediment wave lengths range between 500 and 1000 m and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to a minimum height of 2 m. Seismic profiles showed continuous internal reflectors and several Sediment wave packages were differentiated, being thicker on the crest of each wave and thinner on the downslope flank, indicating that these Sediment waves are upslope-migrating. The Sediment wave formation process was inferred from contemporary hydrodynamic observations, and internal wave activity is suggested to be the most probable mechanism for the Sediment transport and deposition and subsequent maintenance of the Sediment waves over the Gulf of Valencia continental slope.
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Morphobathymetric analysis of the large Fine-Grained Sediment waves over the Gulf of Valencia continental slope (NW Mediterranean)
Geomorphology, 2016Co-Authors: Marta Ribó, Pere Puig, Araceli Muñoz, Claudio Lo Iacono, Pere Masqué, Albert Palanques, Juan Acosta, Jorge Guillén, María Gómez BallesterosAbstract:Abstract Detailed analysis of recently acquired swath bathymetry, together with high-resolution seismic profiles and bottom Sediment samples, revealed the presence of large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope. As many other deep-water Sediment waves, these features were previously attributed to gravitational slope failure, related to creep-like deformation, and are here reinterpreted as Sediment wave fields extending from 250 m depth to the continental rise, at ~ 850 m depth. Geometric parameters were computed from the high-resolution multibeam dataset. Sediment wave lengths range between 500 and 1000 m, and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to minimum values of 2 m high. Sediment waves on the lower part of the slope are quasi-stationary vertically accreting, whereas they show an upslope migrating pattern from the mid-slope to the upper part of the continental slope. High-resolution seismic profiles show continuous internal reflectors, with Sediment waves merging down-section and Sediment wave packages decreasing in thickness downslope. These Sediment packages are thicker on the crest of each individual Sediment wave and thinner on the downslope flank. 210Pb analyses conducted on Sediment cores collected over the Sediment wave fields also indicate slightly higher Sediment accumulation rates on the wave crests. Sediment wave formation processes have been inferred from contemporary hydrodynamic observations, which reveal the presence of near-inertial internal waves interacting with the Gulf of Valencia continental slope. Internal wave activity is suggested to be the preferential mechanism for the transport and deposition of Sediment, and the maintenance of the observed Sediment wave fields.
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Fine Grained Sediment dynamics during a strong storm event in the inner shelf of the gulf of lion nw mediterranean
Continental Shelf Research, 2005Co-Authors: Benedicte Ferre, Albert Palanques, Jorge Guillén, Katell Guizien, Durrieu X De Madron, Antoine GremareAbstract:based upon local sandy Sediment grain size distribution, are in good agreement with the measured SSC profiles during the onset of the storm over the first 2 h. These observations confirm that the measured SSC profiles, during the storm, resulted from the resuspension of the Fine-Grained fraction (o60mm); that is consistent with the grain size of material collected in Sediment traps. Following the first 2 h, numerical simulations suggest that bed armouring occurred, after the surficial Fine-Grained fraction was winnowed. Computations of mud fraction SSC, along a cross-shore transect, which displays a seaward-fining texture of the Sediment, indicate that strong resuspension during this severe storm event only affected water depths shallower than 35 m. This water depth coincides approximately with the transition from sand to mud, on the Gulf of Lion shelf, which is located around 30 m. Computations of the horizontal flux of suspended Sediment flux, due to the current alone, agree with the observations; these indicate that the flux integrated, over the bottom 4.1 m above the seabed, during the storm (14 300 kg m � 2 )i s associated mainly with the Fine-Grained Sediment fraction. The Fine-Grained fraction flux is at least 2.5 times larger than the coarser fractions flux. Likewise, whilst most of the coarse Grained flux (99%) is conFined within few tens of centimetres above the bottom, more than half of the Fine-Grained flux occurs above the bottom boundary layer. r 2005 Elsevier Ltd. All rights reserved.
Jorge Guillén - One of the best experts on this subject based on the ideXlab platform.
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Large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope (NW Mediterranean)
Atlas of Bedforms in the Western Mediterranean, 2016Co-Authors: Marta Ribó, Pere Puig, Araceli Muñoz, Claudio Lo Iacono, Pere Masqué, Albert Palanques, Juan Acosta, Jorge Guillén, María Gomez-ballesterosAbstract:Recently acquired swath bathymetry, high-resolution seismic profiles and bottom Sediment samples have revealed the presence of large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope. Like many other deep-water Sediment waves, these features were previously attributed to gravitational slope failure related to creep-like deformation, and have now been reinterpreted as Sediment wave fields extending from 250 m depth to the continental rise at ~850 m depth. Sediment wave lengths range between 500 and 1000 m and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to a minimum height of 2 m. Seismic profiles showed continuous internal reflectors and several Sediment wave packages were differentiated, being thicker on the crest of each wave and thinner on the downslope flank, indicating that these Sediment waves are upslope-migrating. The Sediment wave formation process was inferred from contemporary hydrodynamic observations, and internal wave activity is suggested to be the most probable mechanism for the Sediment transport and deposition and subsequent maintenance of the Sediment waves over the Gulf of Valencia continental slope.
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Morphobathymetric analysis of the large Fine-Grained Sediment waves over the Gulf of Valencia continental slope (NW Mediterranean)
Geomorphology, 2016Co-Authors: Marta Ribó, Pere Puig, Araceli Muñoz, Claudio Lo Iacono, Pere Masqué, Albert Palanques, Juan Acosta, Jorge Guillén, María Gómez BallesterosAbstract:Abstract Detailed analysis of recently acquired swath bathymetry, together with high-resolution seismic profiles and bottom Sediment samples, revealed the presence of large-scale Fine-Grained Sediment waves over the Gulf of Valencia continental slope. As many other deep-water Sediment waves, these features were previously attributed to gravitational slope failure, related to creep-like deformation, and are here reinterpreted as Sediment wave fields extending from 250 m depth to the continental rise, at ~ 850 m depth. Geometric parameters were computed from the high-resolution multibeam dataset. Sediment wave lengths range between 500 and 1000 m, and maximum wave heights of up to 50 m are found on the upper slope, decreasing downslope to minimum values of 2 m high. Sediment waves on the lower part of the slope are quasi-stationary vertically accreting, whereas they show an upslope migrating pattern from the mid-slope to the upper part of the continental slope. High-resolution seismic profiles show continuous internal reflectors, with Sediment waves merging down-section and Sediment wave packages decreasing in thickness downslope. These Sediment packages are thicker on the crest of each individual Sediment wave and thinner on the downslope flank. 210Pb analyses conducted on Sediment cores collected over the Sediment wave fields also indicate slightly higher Sediment accumulation rates on the wave crests. Sediment wave formation processes have been inferred from contemporary hydrodynamic observations, which reveal the presence of near-inertial internal waves interacting with the Gulf of Valencia continental slope. Internal wave activity is suggested to be the preferential mechanism for the transport and deposition of Sediment, and the maintenance of the observed Sediment wave fields.
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Fine Grained Sediment dynamics during a strong storm event in the inner shelf of the gulf of lion nw mediterranean
Continental Shelf Research, 2005Co-Authors: Benedicte Ferre, Albert Palanques, Jorge Guillén, Katell Guizien, Durrieu X De Madron, Antoine GremareAbstract:based upon local sandy Sediment grain size distribution, are in good agreement with the measured SSC profiles during the onset of the storm over the first 2 h. These observations confirm that the measured SSC profiles, during the storm, resulted from the resuspension of the Fine-Grained fraction (o60mm); that is consistent with the grain size of material collected in Sediment traps. Following the first 2 h, numerical simulations suggest that bed armouring occurred, after the surficial Fine-Grained fraction was winnowed. Computations of mud fraction SSC, along a cross-shore transect, which displays a seaward-fining texture of the Sediment, indicate that strong resuspension during this severe storm event only affected water depths shallower than 35 m. This water depth coincides approximately with the transition from sand to mud, on the Gulf of Lion shelf, which is located around 30 m. Computations of the horizontal flux of suspended Sediment flux, due to the current alone, agree with the observations; these indicate that the flux integrated, over the bottom 4.1 m above the seabed, during the storm (14 300 kg m � 2 )i s associated mainly with the Fine-Grained Sediment fraction. The Fine-Grained fraction flux is at least 2.5 times larger than the coarser fractions flux. Likewise, whilst most of the coarse Grained flux (99%) is conFined within few tens of centimetres above the bottom, more than half of the Fine-Grained flux occurs above the bottom boundary layer. r 2005 Elsevier Ltd. All rights reserved.