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  • Mechanics of sediment transportation and alluvial stream problems
  • Ecoulement ; Fluviatile ; Géographie physique ; Hydrodynamique ; Sédiment alluvial
  • Modelling alluvial fan morphology
  • Alluvial cone ; Fluvial processes ; Hydrology ; Mathematical model ; Model ; Sedimentology
  • A mathematical model which estimates the scale-independent sediment surface profile of alluvial fans has been developed. This model utilizes a diffusive sediment transport model and an unsteady, radial flow, conservation relationship. The model
  • suggests that the overall dimensionless morphology of alluvial fans is governed more by fundamental diffusion principles in sediment deposition than by individual environmental or basin characteristics. A preliminary comparison indicates that this model
  • provides useful qualitative and quantitative information relating to alluvial fan process and morphology.
  • Last-glacial alluvial fan sedimentation in the Lower Derwent Valley, Tasmania
  • Australie ; Cône alluvial ; Derwent, vallée ; Géographie de l'Océanie ; Périglaciaire ; Sédimentologie ; Tasmania
  • Influence of lithologic erodibility on alluvial fan area, western White Mountains, California and Nevada
  • Bassin-versant ; California ; Cône alluvial ; Erodabilité ; Etats-Unis ; Géographie physique ; Géomorphométrie ; Lithologie ; Nevada ; Sédimentologie ; White Mountains
  • Lithology, through its influence on sediment production, may have an important effect on the size of alluvial fans and, hence, on fan-basin morphometric relations. The purpose of this study is to evaluate the influence of lithologic erodibility
  • on the relation between alluvial fan area and drainage basin area.
  • Alluvial fans as records of Holocene sediment yield in the central Great Plains of southwest Nebraska
  • Alluvial cone ; C 14 dating ; Climatic variation ; Geochronology ; Holocene ; Nebraska ; Palaeosol ; Quaternary ; Sediment budget ; Stratigraphy ; United States of America
  • On alluvial fans, increased rates of sedimentation are directly related to increased sediment yields from their watersheds. Since well developed soils imply prolonged landscape stability, soils that are buried by alluvial-fan deposits are evidence
  • of a shift, at least locally, toward increased sediment yields. The objective of this paper is to propose a Holocene history of sediment yield increases in the central Great Plains based on the record that buried alluvial-fan soils provide.
  • A mid-late Holocene flood record from the alluvial reach of the Mahi River, Western India
  • Alluvial plain ; Flood ; Holocene ; India ; Monsoon ; Palaeogeography ; Sedimentation ; Stratigraphy ; Stream
  • Cours d'eau ; Crue ; Holocène ; Inde ; Inde de l'Ouest ; Mousson ; Paléogéographie ; Plaine alluviale ; Stratigraphie ; Sédimentation
  • Flooding of rivers in India is linked with the peak monsoons. In this study, the slackwater deposits in the alluvial reaches of the Mahi river basin have been documented. These occur in the ravines incised during the early Holocene on an alluvial
  • surface comprising sediments of Late Pleistocene age. The stratigraphy of these deposits indicates that the first two slackwater units have resulted due to flooding in a regime of intense monsoon. The other two units, however, represent extreme high
  • Deglacial flood origin of the Charleston alluvial fan, lower Mississippi alluvial valley
  • Alluvial cone ; C 14 dating ; Deglaciation ; Meltwater ; Mississippi ; Palaeo-environment ; Proglacial lake ; Quaternary ; United States ; Valley
  • The main purpose of this research was to determine the genesis and age of the Charleston fan. The AA. reassessed the origin of the fan by comparing the geomorphology and sediment to that of adjacent areas. The age of the fan was constrained
  • by radiocarbon dating of sediment associated with the fan by establishing relationships with adjacent landforms and sediments and by comparing the record with known regional events.
  • Structural geology and the dissection of alluvial fan sediments by mass movement : an example from the southern Italian Apennines
  • Accumulation fluviatile ; Appennino ; Campania ; Cône alluvial ; Flysch ; Géographie physique ; Géomorphologie structurale ; Italie ; Mouvement de masse ; Néotectonique ; Sédimentaire ; Séismicité
  • This paper describes how mass movement is dissecting a relict alluvial fan at the margin of the Sele Valley graben. Rock mass structure and neotectonics are treated here, not as controls upon fan sedimentation, but as a fundamental cause
  • of the instability of inactive fan sediments. The AA. use detailed geological and geomorphological mapping and interpretation to show how faulting and stratigraphic variations have created slump features, subsidence zones, scarpettes and cemented colluvium aprons
  • Active and relict alluvial fans on contact karst of the Vrhpoljska brda hills, Slovenia
  • Alluvial cone ; Alluvium ; Flysch ; Hill ; Karst ; Limestone ; Slovenia
  • karst area two types of alluvial fans appear on carbonate bedrock. Members of the first type are ordinary alluvial fans with active alluvial processes where flysch derived sediment covered limestone surface in a distinct fan shape. - (L'A.).
  • Sedimentological study of Gomti river sediments, Uttar Pradesh, India. Example of a river in alluvial plain
  • Late Quaternary alluvial stratigraphy of a low-order tributary in central Texas, USA and its response to climate and sediment supply
  • This paper presents the late Quaternary alluvial stratigraphic study of a low-order tributary in central Texas, using Cowhouse Creek as a case study. The AA. correlate episodes of stream incision and alluviation to climate records and to previous
  • alluvial stratigraphic work conducted along the Brazos River. The temporal alluvial stratigraphic framework of the bedrock-confined Cowhouse Creek valley is out of phase with the alluvial sequence in the larger Brazos River valley.
  • Surface sediment characteristics and present dynamics in alluvial fans of the central Spanish Pyrenees
  • Alluvial cone ; Geomorphometry ; Grain size distribution ; Land use ; Mudflow ; Plant canopy ; Pyrénées ; Sedimentology ; Slope dynamics ; Spain ; Watershed
  • Three alluvial fans in the Ribera de Biescas, upper Gállego Valley, and central Spanish Pyrenees, have been studied in order to explain the most recent changes and to identify the spatial organization of the sediment. In the alluvial fans surveyed
  • , the proximal area is dominated by debris flows, which pass downslope into transitional and fluvial deposits. The AA. explain the most recent activity in alluvial fans in relation to land-use and plant cover changes affecting their catchments during the last few
  • Geomorphology and sedimentology of the Toro Amarillo alluvial fan in humid tropical environment, Costa Rica
  • Costa Rica ; Cône alluvial ; Eruption volcanique ; Granulométrie ; Géographie de l'Amérique ; Géomorphodynamique ; Météorisation ; Sédimentologie ; Toro Amarillo ; Zone intertropicale
  • sédiments. Les manifestations volcaniques de 1963-1965 ont produit d'importants changements dans les caractéristiques de ce cône alluvial.
  • Caractéristiques géomorphologiques et sédimentologiques du cône alluvial Toro Amarillo situé dans un milieu tropical humide. De courtes périodes actives sont séparées par de longues périodes inactives caractérisées par l'érosion météorique des
  • Rational regime model of alluvial channel morphology and response
  • for alluvial systems. Discharge, sediment supply (quantity and calibre) and valley gradient are accepted as independent governing variates. The model is used to define a dimensionless alluvial state space characterized by aspect ratio, relative roughness
  • A theoretical model is developed for predicting equilibrium alluvial channel form. The concept of greatest relative stability, achieved by maximizing resistance to flow in the fluvial system, is presented as the basis for an optimization condition
  • Soils in the Holocene alluvial sediments of the Rio Fraja Valley, Spain : in situ or soil-sediments ?
  • of erosion, sedimentation and pedogenesis during the last 4000 years. The data sets allow to distinguish soils formed in situ from transported soil-sediments. The AA. suggest that in alluvial sequences magnetostratigraphic records can be used to distinguish
  • In the Holocene alluvial deposits of the Fraja Valley (Cadiz Province, SW Spain) the AA. have used geomorphological, mineralogical, sedimentological and paleomagnetic data with dating based on radiocarbon and pottery to distinguish episodes
  • periods of land surface stability, when pedogenetic processes prevailed under a vegetation cover, and morphodynamically active periods, in which soil erosion, transportation and sedimentation predominated.
  • Sediment transfer and transformation of an alluvial valley floor : the River South Tyne, Northumbria, U.K.
  • Analysis of lateral and vertical channel change over a 115 year period, the extent of actively reworked gravels, and identification of metals in alluvial units, show five sedimentation zones separated by more stable reaches. Aggradation in the late
  • nineteenth century was followed by a period of storage and local reworking, and then incision. The intricate response of the channel system to historic changes in sediment supply is not readily described by either a complex response model or a simple
  • Coarse bed load transport in an alluvial gravel bed stream, Dupuyer Creek, Montana
  • Alluvial channel ; Montana ; River bed ; Sampling ; Sediment load ; Sediment transfer ; Stream ; United States of America
  • Charge solide ; Chenal alluvial ; Cours d'eau ; Echantillonnage ; Etats-Unis ; Lit fluvial ; Montana ; Transfert sédimentaire
  • Deformation of a modern alluvial plain
  • Alluvial plain ; Flood ; Netherlands (The) ; Sedimentary structure ; Sedimentation ; Stream
  • Cours d'eau ; Crue ; Pays-Bas ; Plaine alluviale ; Structure sédimentaire ; Sédimentation
  • The alluvial plain of the Waal River (The Netherlands) showed large flow-lobe like structures after it had fallen dry following floodings. The deformation is ascribed to a rare coincidence of hydrological, topographic, and weather conditions. Local
  • A stability criterion inherent in laws governing alluvial channel flow
  • Carrying capacity ; Channel geometry ; Mathematical hydrology ; Runoff ; Sediment transport ; Stream ; Stream flow
  • and bedload transport formulae. This study provides support for the use of the criteria of MFE, maximum sediment transporting capacity and minimum stream power for understanding the operation of alluvial rivers, and also addresses limitations to the direct
  • The stability criterion of maximum flow efficiency (MFE) has previously been found inherent in typical alluvial channel flow relationships, and this study investigates the general nature of this criterion using a wider range of flow resistance
  • Holocene alluvial sediment storage in a small river catchment in the loess area of central Belgium
  • Belgium ; Holocene ; Human impact ; Loess ; Sediment budget ; Soil erosion ; Watershed
  • The aims of this study are to estimate the sediment volume stored in the Holocene alluvium of a representative small river in the Belgian loess belt and to establish a chronology of sediment deposition. Furthermore, estimates of Holocene soil
  • erosion intensities and colluvial sediment storage from previous work in this catchment are supplemented with the new data to establish a preliminary sediment budget for this river catchment.