inscription
Portail d'information géographique

Résultats de la recherche (3348 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Rates of surface processes on slopes, slope retreat and denudation: a comment and a reply
  • Rates of surface processes on slopes, slope retreat and denudation: a reply
  • Slopes and slope processes
  • Land use ; Mass movement ; Rill wash;Runoff ; Slope ; Slope dynamics ; Soil erosion ; Tectonics
  • Slopes and slope processes
  • Debris flow ; Erosion rate ; Mass movement ; Model ; Precipitation ; Slope ; Slope dynamics ; Soil ; Soil erosion ; Vegetation
  • Slopes and slope processes
  • Bibliography ; Geotechnics ; Land use ; Mass movement ; Model ; Slope ; Slope dynamics ; Soil erosion
  • Paraglacial modification of slope form
  • Deglaciation ; Geomorphometry ; Glacial features ; Gully erosion ; Mudflow ; Norway ; Slope ; Slope gradient
  • The morphological consequences of paraglacial modification of valley-side drift slopes are investigated at 6 sites in Norway. Here, paraglacial slope adjustment operates primarily through the development of gully systems, whereby glacigenic sediment
  • is stripped from the upper drift slope and redeposited in debris cones downslope. This results in an overall lowering of average gradient along gully axes.
  • On distribution of slope deformations in the north-eastern part of the Vizovická vrchovina Highland in Eastern Moravia
  • Czech Republic ; Geomorphological mapping ; Geomorphology ; Moravia ; Slope ; Slope dynamics
  • Altogether ninety-three localities of slope deformation were identified in the NE parts of the Vizovice Highland, during the detailed geomorphological mapping. Special attention was paid to the deep-seated slope deformations in the central
  • mountainous slopes of the Highland. - (MS)
  • A lejtoprofil-analizis modszereinek alkalmazasa a lejtoformalodas vizsgalatara Nagyborzsony kornyékén. (Application of slope profile analysis methods in the investigation of slope development in the region of near Nagyborzsony)
  • The object of this study is to examine how results of slope profile analysis might be used in explaining slope form and slope development. (CK).
  • Flared slopes, footslopes, and the retreat of overhanging slopes : examples of convergent landform development
  • Australia ; Cave ; Concept ; Erosion ; Geomorphogenesis ; Granite ; Piedmont ; Slope ; Slope dynamics ; Weathering ; Western Australia
  • Flared slopes are concave slopes thought by some to be created by subsurface weathering followed by stripping. The AA. believe that concave slopes may also be formed by subaerial weathering, and that the retreat of such slopes creates rectilinear
  • footslopes. Such rectilinear slopes have also been related to flared slopes. The same landforms have been used in the past to illustrate both modes of formation, as illustrated by various examples including Ayers Rock and Hyden Rock in Australia
  • . The combination of concave and rectilinear slopes may produce convergent landforms that can be formed by different processes.
  • Stratified debris deposits on the southern slope of the Magaliesberg in the vicinity of Hornsnek
  • Climatic variation ; Geomorphogenesis ; Multivariate analysis ; Palaeogeography ; Slope deposit ; South Africa
  • The aims of this study were to determine : the thickness of the slope deposits over the southern slope of the Magaliesberg, near Pretoria, South Africa; whether the slope deposits on the Magaliesberg consist of more than one sedimentary layer
  • ; the continuity of the slope deposits over the slope; the depositional circumstances of the deposits and whether there is a possible correlation between the slope deposits and quaternary climatic fluctuations.
  • Variations in slope components during large magnitude floods, Wisconsin
  • Many paleodischarge reconstruction techniques assume one-to-one correspondence between water surface slope and slope measured from a topographic map. The assumption that map slope or water surface slope, however, can be directly substituted
  • for energy slope, involves unknown degrees of error. This research shows that energy gradients are generally overpredicted by both water surface slope (mean = 44 percent) and map slope (mean = 11 percent).
  • The effect of slope length on the amont and size distribution of eroded silt loam soils : short slope laboratory experiments on interrill erosion
  • Experimentation ; Grain size distribution ; Loam ; Rainfall simulation ; Rill wash ; Sandy soil ; Slope ; Slope gradient ; Soil erosion ; Splash
  • The data of rainfall simulation experiments on a sandy loam and a loamy sand were compared to assess the effect of slope length on the soil loss from short slopes. The experimental results indicated that the slope length effect is different
  • Slope aspect, slope length and slope inclination controls of shallow soils vegetated by sclerophyllous heath - links to long-term landscape evolution
  • Australia ; Biogeography ; Heath ; Impact ; New South Wales ; Sandstone ; Slope ; Slope dynamics ; Slope gradient ; Soil erosion ; Vegetation
  • On upland Triassic sandstone slopes of the western Blue Mountains in Southeastern Australian highlands, nonswamp, sclerophyllous heath (shrub-dominated vegetation) on shallow soils is commonly found downslope and adjacent to sclerophyllous forest
  • on deeper soils. The AA. test the strength of the relationship between aspect and heath/shallow soil distribution, and consider other possible controls related to erosion thresholds and slope inclination. Shallow soils vegetated by heath are more strongly
  • controlled by topographic factors other than slope aspect and the influence of aspect on long-term landform evolution is overwhelmed by other processes as landscape dissection increases.
  • Slopes and slope processes
  • Applied geomorphology ; Bibliography ; Landslides ; Mass movements ; Slope dynamics ; Slopes ; Soil erosion
  • The stability of slopes in the Ardennes region
  • The mode of the measured slope angle values does not differ between the different lithological units. It is suggested that in periglacial times the slopes became unstable, due to a blockage of the ground-water by the permafrost in the subsurface
  • . At that time the slope population changed from the upper threshold value for dry regoliths to the lower one for completely saturated regoliths via a flattening of the slopes. (LW).
  • The determination of suction-controlled slope stability in humid temperate environments
  • Hydrology ; Model ; Permeability ; Scotland ; Slope ; Slope dynamics ; Soil properties ; Temperate zone ; United Kingdom
  • In this paper two models are employed to assess whether hillslopes in humid temperate environments may be suction controlled. In 1988 a series of storms produced several shallow planar slope failures, in freely-draining, permeable soils on slopes
  • in the Glen Livet Estate, Scotland. The two models, when applied to these slope failures, indicate the possibility that slopes may fail under unsatured conditions, and that their stability is thus controlled by the minimum suction which may develop
  • Effects of slope angle on mass movement by tree uprooting
  • Forest ; Mass movement ; Michigan ; Regression analysis ; Sandy soil ; Slope ; Slope dynamics ; Slope gradient ; United States of America
  • An examination of 189 well-delineated mounds and pits in sandy soils of northern lower Michigan, all presumably formed by tree uprooting, was used to determine the effects of slope angle on morphology and volume, and to assess the potential
  • importance of uprooting to mass movement. Data indicate that mound and pit volumes increase with increasing slope angle, suggesting that on gentle slopes more of the disturbed soil wastes off the mound, back into the new pit.
  • Effect of grain diameter and packing condition on the avalanching depth on a slope composed of dry granular materials
  • Experimentation ; Grain size distribution ; Honshu ; Japan ; Mass movement ; Slope ; Slope dynamics
  • To examine the depth of avalanching taking place on a slope at a critical angle of repose, tilting tests were performed in the laboratory using slopes made of granular materials such as gravels and glass beads. The AA. conclude that the avalanche
  • depth on slopes made of granular materials is determined by the diameter of the slope materials and by their packing state.
  • Assessing the influence of mountain slope morphology on pediment form, South-Central Arizona
  • Alluvial cone ; Arid area ; Arizona ; Digital elevation model ; Geomorphology ; Mountain ; Numerical model ; Pediment ; Principal components analysis ; Slope gradient ; United States of America
  • The aim of this research is to determine if certain geomorphic characteristics of mountain slopes backing bedrock pediments and alluvial slopes discriminate their occurrence at the slope base. Principal component analysis results indicate mountain
  • slopes above bedrock pediments differ significantly from those above alluvial slopes.
  • Slope geometry resulting from the spatial variation of soil permeability
  • Mass movement ; Model ; Permeability ; Slope ; Slope dynamics ; Slope gradient ; Soil erosion ; Soil properties ; Splash
  • In a series of computer simulations the question is treated: what is the impact of spatial differences in infiltration on long-term slope development? The computations suggest that different slope profils can be created under ensystemic conditions
  • not pnly by process-specific charakteristics but also due to differences in infiltration. For example, a convex sllope profil is formed, if there is declining infiltration along slope length. Increasing infiltration downslope results in a concave slope
  • profile whereas constant infiltration yields a more or less rectilinear slope profile.