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  • Size distributions of saltating grains : an important variable in the production of suspended particles
  • Aeolian dust ; Aeolian features ; Aeolian transport ; California ; Grain size distribution ; Lake ; Loam ; Sand ; Soil properties ; United States of America
  • The AA. present newly developed size distribution information for saltating particles for experiments where the ratio Fa/q had been measured. The data may then be examined to see if any clear-cut behaviour of Fa/q with size distribution can
  • be observed. The results for the Owens Lake loam soil of Gillette et al. (1997) are used in the discussion for comparison. Soils from which the saltating particles originated (parent soils) were processed for size distributions in the same ways as the airborne
  • Belgium ; Grain size distribution;Granulometry ; Precipitation ; Rill wash;Runoff ; Sediment transport ; Slopes ; Soil erosion
  • . Different sediments were used in order to study the effect of grain size. The proposed relationship show considerable variations with grain size and there is only a minor effect of rainfall on the transport capacity which also seems to be grain size
  • Remanence characteristics of different magnetic grain size categories at Xifeng, Central Chinese Loess Plateau
  • China ; Grain size distribution ; Guizhou ; Loess ; Palaeoclimatology ; Palaeogeography ; Palaeomagnetism ; Palaeosol ; Pedogenesis ; Plateau
  • by superparamagneic, single domain, and multidomain ferrimagnets at low temperatures and use these as a measure of the relative importance of these grain-size fractions in the magnetic enhancement of paleosols.
  • Grain-size sorting in meander bends containing large woody debris
  • Channel geometry ; Grain size distribution ; Illinois ; Meander ; Photointerpretation ; River bed ; Stream ; United States of America
  • This study examines the influence of large woody debris, LWD, on grain-size sorting in 3 meander bends in a low-gradient river in the Midwestern United States, in northern Illinois. The detailed nature of the modifications appears to be highly
  • Development of algebra algorithms for automated generation of grain-size distribution maps
  • Algorithm ; Automated mapping ; Connecticut ; Geographical information system ; Grain size distribution ; Italy ; Pool ; Sedimentology ; Spatial distribution ; Strait ; United States of America ; Veneto ; Venice
  • Algorithme ; Cartographie automatique ; Connecticut ; Distribution spatiale ; Détroit ; Etats-Unis ; Granulométrie ; Italie ; Lagune ; Système d'information géographique ; Sédimentologie ; Veneto ; Venezia
  • In this work, 4 map algebra (MA) algorthms are written in a GIS environment to automatically produce maps depicting the spatial distribution of sediment texture classes based on the most frequently used grain size TDs : the Shepard classification
  • and Flemming classification for sand-silt-clay components, and the Folk et al. classification and Blair and McPherson classification for sand-gravel-mud components. The proposed method allows rapid assessments by producing map distributions of the parameters
  • Aeolian features ; Arid area ; Burkina ; Discriminant analysis ; Drought ; Eolian deflation ; Grain size distribution ; Land use ; Microstructure ; Sahel ; Sedimentology ; Wind erosion
  • The aim of this paper is to identify possible sources for the material found in nebkhas in northern Burkina Faso. Grain-size distributions of nebkhas sediments and five other subenvironments were analyzed using univariate and multivariate methods
  • . Quartz-grain surface textures were studied by Scanning Electron Microscopy (SEM). The SEM and grain-size analyses together indicate that the nebkhas have experienced considerable recent aeolian abrasion and sorting.
  • The size characteristics of the drifting sand grains in al-Hasa oasis, Saudi Arabia
  • Distribution des transports de sable selon la granulométrie et la vitesse du vent.
  • Downstream variation in grain size along an Alpine river : analysis of controls and processes
  • Braided channel ; Grain size distribution ; Gravel ; Human impact ; Hydraulic works ; Italy ; River bed ; Sediment load ; Stream ; Trentino-Alto Adige
  • This study concerns downstream variation in bed material size along a 115-km reach of the Piave River in north-eastern Italy. This river drains a region producing high sediment yields (the Dolomites and the Prealps) and has a braided pattern along
  • half of its length. The A. analyses the changes of bed material size in the downstream direction and explains these changes in the light of both natural and anthropogenic factors.
  • Dispersing sandy soil for the measurement of particle size distributions using optical laser diffraction
  • Grain size distribution ; Methodology ; Niger ; Sandy soil ; Soil ; Soil properties ; X-ray diffraction analysis
  • to the intensity of dispersion using temporal variation and microscopic evidence. Problems in blending the results from 2 separate lenses are discussed and consideration is also given to subsampling bias and its contribution to the resultant grain-size distribution.
  • Distribution of organic carbon in bed sediments of Manoa stream, Oahu, Hawaii
  • Biogeochemistry ; Carbon ; Ecosystem ; Grain size distribution ; Hawaii ; Organic materials ; Sediment load ; Spatial distribution ; Stream ; Tropical zone ; Watershed
  • Bassin-versant ; Biogéochimie ; Carbone ; Charge solide ; Cours d'eau ; Distribution spatiale ; Ecosystème ; Granulométrie ; Hawaii ; Matière organique ; Zone intertropicale
  • sediment grain size in a tropical perennial stream, to examine the influence of individual grain size fractions on the mass of OC stored over a 6 km channel length, and to explore the longitudinal distribution of bed sediment grain size and OC within Manoa
  • Carrying capacity ; Catchment area;Watershed ; Drainage network ; Fluvial processes ; Grain size distribution;Granulometry ; India ; Seasonal variation ; Sedimentology ; Statistics
  • To evaluate the magnitude of variation in grain size distribution in the Krishna river, bed sediments and suspended sediments collected along the length of the river have been studied. There are both temporal and seasonal variation in the grain size
  • distribution of suspended sediments. The statistical parameters show the change along the river in a non-linear fashion which may be due to human interference and due to different types of sediments contributed by tributaries to the Krishna river.
  • Statistical analysis of grain size distribution in Pleistocene sediments from Lake Biwa, Japan
  • Time series of grain-size distributions from Pleistocene sediments deposited in Lake Biwa during the past 550 millennia show dominant periods of 40,000 and 20,000 yr that are very close to those predicted by the Milankovitch theory, as well
  • The statistical analysis of the sand grain size distribution of Al Ubaylah barchan dunes, Northwestern Ar-Rub-Alkhali desert, Saudi Arabia in Saudi Arabia. (L'Arabie Saoudite)
  • Ar Rab' Al-Khali ; Arabie saoudite ; Barkhane ; Distribution statistique ; Dune ; Désert ; Eolien ; Granulométrie ; Géographie de l'Asie ; Sable
  • Validation of algorithms to retrieve snow grain size and impurities using airborne multispectral scanner data of eastern Hokkaido
  • Albedo ; Cloud ; Data processing ; Grain size distribution ; Hokkaido ; Japan ; LANDSAT ; Pool ; Remote sensing ; Sea ice ; Snow ; Spectral reflectance
  • ) in eastern Hokkaido, Japan. The algorithms using remote-sensing data to retrieve the snow grain size and the concentration of snow impurities were used for a theoretical Bidirectional Reflectance Distribution Function (BRDF) model of the snow surface
  • Preliminary validation of algorithms to retrieve snow grain size and impurities was conducted by applying them to Airborne Multispectral Scanner (AMSS) data at the flat snowfield (February 1998) and on sea ice in Saroma Lagoon (February 2001
  • Harmattan dust deposition and particle size in Ghana
  • Aeolian dust ; Aeolian features ; Agropedology ; Arid area ; Ghana ; Grain size distribution ; Loess ; Research technique ; Sampling ; Sediment transport
  • This paper describes the development of sampling techniques for monitoring the Harmattan dust deposition in Ghana. It compares 3 different methods to trap the Harmattan dust and describes the difference in amount and particle size distribution
  • Provenance and dispersion of fluvial, beach and shelf sands in the Bassa Maremma coastal system (central Italy): an integrated approach using Fourier shape analysis, grain size and seismic data
  • Central Italy ; Coastal dynamics ; Coastal environment ; Coastal sedimentation ; Grain size distribution ; Italy ; Seismic method ; Statistics
  • This study is an analysis of geographically related surface samples from offshore, fluvial and sandybeach environments, along a section of coast northeast of Rome, Italy. It examines the potential of size and Fourier shape analysis to define
  • Fractality of grain composition of debris flows
  • China ; Fractals ; Grain size distribution ; Gully erosion ; Mudflow ; Porosity ; Sedimentology ; Slope ; Soil properties
  • This paper focuses on the features of grain composition, based on data from various samples of debris flows in different regions and gullies, and their potential actions on debris flows. Samples are collected from gullies in Beijing, Gansu, Sichuan
  • Grain size distribution ; Mineralogy ; Palaeosol ; Pedogenesis ; Soil ; Soil properties
  • The AA. determined the quantitative mineralogical compositions of various grain size fractions of soil samples that were collected from 10-cm depth intervals. The results show that the grain size distribution curve of a given mineral is related
  • Aggregate ; Grain size distribution ; Methodology ; Sedimentology ; Soil ; Soil properties ; X-ray diffraction analysis
  • The aim of this study is, first, to determine if the effective particle size distribution measured by a laser diffractometer is comparable to the effective particle size distribution measured by the sieve-pipette method, and second, to determine
  • Mining soil databases for landscape-scale patterns in the abundance and size distribution of hillslope rock fragments
  • California ; Grain size distribution ; Hawaii ; Mining activity ; Precipitation ; Regolith ; Rock fragment ; Sierra Nevada ; Slope ; Slope dynamics ; Soil properties ; Statistical distribution ; United States of America ; Washington State
  • California ; Cascade Mountains ; Distribution statistique ; Dynamique de versant ; Etats-Unis ; Exploitation minière ; Fragment de roche ; Granulométrie ; Hawaii ; Météorisation ; Propriétés du sol ; Précipitation ; Régolithe ; Sierra Nevada
  • The AA. explored the utility of soil survey databases for data mining, with the goals of identifying landscape-scale patterns in the abundance and size distribution of rock fragments (diameter D>2mm) and potential controls on grain size production
  • and transport, constructed depth-averaged grain size distributions and calculated the mass fraction of rock fragments and the median rock fragment grain size. They also categorized as bimodal, size distributions with a clear ‘breakpoint’ between fine and coarse