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  • Differential bedload transport rates in a gravel-bed stream : a grain-size distribution approach
  • The objective of this paper is to investigate whether the systematic variations of bedload grain-size distributions observed in Oak Creek can serve as the basis for calculations of transport rates of different size fractions. The approach will rely
  • on the Rosin distribution and how its parameter depend on the flow discharge and bed stress. The total transport rate, which is also a function of the discharge or stress, is then apportioned within the distribution of grain sizes of the Rosin distribution
  • to yield frequency curves for the differential transport rates of the spectrum of grain sizes.
  • Bias and precision of percentiles of bulk grain size distributions
  • Carrying capacity ; Grain size distribution ; Gravel ; Methodology ; Sampling ; Sediment transport ; Sedimentology ; Statistical distribution ; Statistics ; Stream
  • Capacité de charge ; Cours d'eau ; Distribution statistique ; Echantillonnage ; Granulométrie ; Gravier ; Méthodologie ; Statistique ; Sédimentologie ; Transport sédimentaire
  • Grain size analysis is a standard tool in the study of sediments. This paper presents a method for computer sampling experiments on variability in percentiles of a bulk grain size distributions (GSD), results for commonly used size percentiles
  • Bias in grain size distribution of deposited atmospheric dust due to the collection of particles in sediment catchers
  • Aeolian dust ; Aeolian features ; Experimentation ; Grain size distribution ; Instrumentation ; Sedimentology ; Statistical bias ; Wind speed
  • distribution of the sediment. This paper presents wind tunnel results for 5 dust deposition samplers and 5 wind velocities. The catcher's effect on the grain size was apparent in all experiences.
  • This study investigates how dust deposition samplers affect the grain size characteristics of the sediment they catch. Some particle fractions are collected more efficiency than others, resulting in a modification of the original grain size
  • A numerical model for shore-normal sediment size variation on a macrotidal beach
  • Coastal dynamics ; Coastal environment ; Grain size distribution;Granulometry ; Intertidal zone ; Isle of Man ; Model ; Numerical model ; United Kingdom
  • This paper describes a computer simulation model which is designed to predict the selective shore-normal sorting of grain sizes in the nearshore environment. The predicted grain size is used in an hydraulic interpretation of grain size distribution
  • of the intertidal profile, based on the hydrodynamic variations over a tidal cycle on a macrotidal beach. The model is successful in predicting the broad pattern of increasing grain size in the onshore direction which has been observed in nature.
  • GRADISTAT : a grain size distribution and statistics package for the analysis of unconsolidated sediments
  • Computing ; Grain size distribution ; Methodology ; Sedimentology ; Statistics
  • Grain size analysis is an essential tool for classifying sedimentary environments. A computer program called GRADISTAT has been written for the rapid analysis of grain size statistics from any of the standard measuring techniques, such as sieving
  • and laser granulometry. The program runs within the Microsoft Excel spreadsheet package and is extremely versatile, accepting standard and non-standard size data, and producing a range of graphical outputs including frequency and ternary plots.
  • Differential bedload transport rates in a gravel-bed stream : a grain-size distribution approach. Discussion and reply
  • Carrying capacity ; Fluvial processes ; Grain size distribution;Granulometry ; Sediment transport
  • on the changing grain-size distributions as the flow discharge and mean bottom stress increase.
  • Shih and Komar argue here that the dimensional analysis of Diplas obscures the relationship between the transport rate and grain size, and in fact leads to a complex implausible dependence. In contrast, their approach allows one to better focus
  • Grain-size distribution patterns of a point bar system in the Usri River, India
  • Bank erosion ; Grain size distribution ; Hydrodynamics ; India ; Model ; Sedimentary structure ; Spatial distribution ; Statistics ; Stream ; West Bengal
  • Cours d'eau ; Distribution spatiale ; Erosion des berges ; Granulométrie ; Hydrodynamique ; Inde ; Modèle ; Statistique ; Structure sédimentaire ; West Bengal
  • Grain-size distribution patterns in a point bar system of the Usri River, India, were critically analysed in the light of log-normal, log-hyperbolic and log-skew-Laplace distribution models. Sand samples were collected from the cross-bedding foreset
  • of different sizes of bedform; the aims were to : study whether bedforms heights have any role in grain-size distribution patterns, offer a best-fit statistical model, study the downstream variation of size-sorting in a point bar system, and study the mechanism
  • of grain sorting.
  • Aeolian deposition of dust over hills : the effect of dust grain size on the deposition pattern
  • Aeolian dust ; Aeolian features ; Aeolian transport ; Belgium ; Experimentation ; Flemish Brabant ; Grain size distribution ; Impact ; Leuven ; Topography
  • Wind tunnel experiments were conducted to investigate the effects of topography on the grain size characteristics of aeolian dust deposits. Experiments were performed on 3 isolated hills having various size and aspect ratios. The longitudinal
  • profile of the median grain diameter was investigated for each hill. The wind tunnel experiments show that the grain size characteristics of aeolian dust deposits are affected by topography.
  • The use of grain-size distribution patterns to elucidate aeolian processes on a transverse dune of Thar Desert, India
  • Aeolian features ; Aeolian transport ; Arid area ; Desert ; Dune ; Grain size distribution ; India ; Model ; Rajasthan ; Statistical distribution
  • Distribution statistique ; Domaine aride ; Dune ; Désert ; Eolien ; Granulométrie ; Inde ; Modèle ; Rājasthān ; Transport éolien
  • The grain-size distribution of aeolian dune sands in the Thar Desert, India was analyzed and compared with 3 model distributions – log-normal, log-hyberbolic and log-skew-Laplace – to determine the best-fit statistical model. In total, 51 samples
  • . It is suggested that the main criteria for the development of a normal distribution is the lack of skewed fractions and the concentration of the narrow, intermediate size fractions in the final grain size distribution.
  • A hybrid method for size characterisation of coarse subsurface fluvial sediments
  • Grain size distribution ; Methodology ; Model ; River bed ; Sampling ; Sedimentation ; Sedimentology ; Stream
  • This paper introduces and evaluates a novel method for ascertaining the grain-size distribution of subsurface sediments that involves profoundly less sampling effort than standard methods. It is based on hybrid sampling principles previously applied
  • to the construction of synthetic surface grain-size distributions. The method is developed from an empirical demonstration of the approximate similarity of surface and subsurface grain-size distributions when compared over a common range of sizes. Subsurface hybrid
  • models are found to provide good facsimilies of grain-size distributions using standard criteria. The technique is presented as an expedient alternative to standard methods for large, perennial gravel-bed rivers.
  • Vertical distribution of grain-size parameters of drifting particles during sand storms in the Taklamakan desert, Central Asia
  • Aeolian features ; Arid area ; China ; Desert ; Dust storm ; Experimentation ; Grain size distribution ; Sand ; Sedimentology ; Wind speed
  • The vertical distributions of grain-size parameters of drifting sand flux during sand storms in the Taklamakan Desert, were investigated through field observation and laboratory wind-tunnel tests. The results show that grain-size parameters
  • of the drifting sands near the ground surface are similar to those of the source deposits. Regional differences in the vertical distribution of grain-size compositions are affected by source deposits, wind speeds, and transport rates, but source has more influence
  • Grain-size analysis by laser diffractometry : comparison with the sieve-pipette method
  • Clay mineral ; Grain size distribution ; Methodology ; Soil ; Soil properties ; Soil science ; X-ray diffraction analysis
  • Results of a traditional sedimentation technique for grain-size analysis (the sieve-pipette method) were compared with those of a laser diffraction grain-size analyser, the Coulter LS-100. Milled quartz samples and silty soil samples were used
  • Grain-size analysis of surface material under wind erosion using the effective surface concept
  • Aeolian features ; Aeolian transport ; Concept ; Experimentation ; Grain size distribution ; Methodology ; Roughness ; Wind erosion
  • This paper deals with the temporal variation in the grain size of surface material using an analytical method based on the effective surface concept. This method is applied to data collected in 2 series of wind tunnel experiments. The results
  • are compared with findings of other studies on aeolian sediment transport rate for individual grain size classes over time.
  • High-resolution grain-size characterisation of gravels bars using imagery analysis and geo-statistics
  • Geostatistics ; Grain size distribution ; Gravel ; Image analysis ; Remote sensing ; Spain ; Stream ; Thematic mapping
  • Mesures de la taille des grains à partir d'échantillonnage du terrain. Signature de la texture des séries de dimensions des grains. Relation entre dimension des grains et texture des images. Cartographie des dimensions des grains.
  • The effects of grain abrasion and disaggregation on 137 Cs concentrations in different size fractions of soils developed on three different rock types
  • Australia ; Erosion ; Geochemistry ; Grain size distribution ; Isotope analysis ; Sediment transport ; Sedimentology ; Tracer ; Victoria ; Watershed
  • of disaggregation and grain abrasion on the distribution of 137 Cs with respect to particle size fractions were studied in soils derived from the 3 different rock types of the Tarago catchment.
  • Bulk sampling of coarse clastic sediments for particle-size analysis
  • Grain size distribution;Granulometry ; Methodology ; Sedimentology ; United Kingdom
  • A guide is provided to the minimum sample masses required to obtain reproducible measures of the particle-size distributions of coarse sediments. This is based on studies of the actual particle-size distributions of a range of clastic deposits
  • Source identification of suspended sediment from grain-size distributions : I. application of nonparametric statistical tests
  • Grain size distribution ; Hokkaido ; Japan ; Sedimentology ; Statistics ; Suspended load ; Tracer ; Watershed
  • In this study, a new technique for identifying the source of suspended sediment is described, based on a comparison of overall grain-size distributions. Suspended sediment flux (SSF) supplied from sediment generated by logging and deposited
  • , was estimated from grain-size distributions of the river-suspended sediment based on nonparametric statistical tests.
  • Grain-size distributions of wind-eroded material above a flat bare soil
  • Aeolian features ; Aeolian transport ; Cultivated land ; Dust storm ; Grain size distribution ; Sedimentology ; Soil erosion ; Texas ; United States of America ; Wind erosion
  • The objectives of this research were to investigate through field measurements the vertical distribution of eroded soil materials above eroded farmland during sand-dust storms, including consideration of mass flux and grain-size parameters
  • . This paper reports the results of an examination of the grain-size distribution in a sandy loam soil in Big Spring, Texas, during sand-dust storms in the 1995 wind-erosion season.
  • Bohemia ; Catchment area;Watershed ; Czech Republic ; Fluvial processes ; Grain size distribution;Granulometry ; Microstructure ; Mineralogy ; Pollution ; Sedimentology
  • Part of the project to study the distribution and transport of pollutants in the Bohemian part of the Labe river involved the determination of the mineral association in recent sediments, the grain-size distribution and expression of the effect
  • of the river catchment geological setting, of its relief and of weathering on the composition of the particulate bed material. As it is generally accepted that the smaller grain-size of the sediment fraction binds the greatest amount of trace toxic elements
  • , the greatest attention has been devoted to the silt/clay size category.
  • A study of minor reliefs and grain size distribution on alluvial fans in Central Japan.
  • Comparaison de la dynamique des eaux sur les cônes alluviaux en la présence (état actuel) ou l'absence (état ancien) de digues. Dans le second cas les chenaux de basses-eaux sont moins sinueux, et les grains plus fins. (A. Berque).