inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (2887 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • 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.
  • Sedimentology and fabric characteristics of subaerial slope and alluvial cone deposits in Northen Calabria (Southern Italy)
  • Calabria ; Geomorphometry ; Italy ; Mountain ; Sediment transport ; Sedimentology ; Slope deposit
  • This work focuses on the transport processes, sedimentology and clast fabric of slope deposits cropping out in active depositional environments, widespread between 900 and 1000 m in altitude, close to Mormanno, in Northen Calabria. - (NF)
  • Slope deposits in the Upper Nalón River Basin (NW Spain) : an approach to a quantitative comparison
  • Altitude ; Asturias ; Lithology ; Slope deposit ; Slope dynamics ; Spain ; Statistics ; Topography ; Watershed
  • The Upper Nalón River Basin (Cantabrian Mountains, NW Spain) exhibits a variety of slope processes and deposits including landslides, rockfall and soil creep. Geomorphic maps were used to quanitatively ascertain the relationships between
  • these deposits and topographic characteristics of exposure, gradient and altitude at the nodes of a square grid with 250-m spacing (N=926). A correspondance analysis allows the analysis of qualitative and quantitative variables. The results suggest that lithology
  • is the main conditioning factor of the differences and similarities between deposits.
  • Origin and palaeoclimatic significance of the Pleistocene slope covers in the Cracow Upland, southern Poland
  • Grain size distribution ; Lithology ; Loess ; Palaeoclimatology ; Periglacial features ; Pleistocene ; Poland ; Quaternary ; Slope deposit ; Weathering
  • Periglacial slope covers in the southern part of the Cracow Upland can be grouped in 5 genetic categories : slope loess, washed loess, weathered debris, scree deposits, low-density flow deposits, and solifluctites or high-density flow deposits
  • . They differ from each other with respect to their morphological position in relation to the slope, and in lithological characteristics. It was found that successive generations of slope deposits can be distinguished according to their degree of chemical
  • weathering. This paper therefore contributes to a discussion on the possibility of paleoclimate reconstruction based on slope deposits analyses.
  • Hydrological characteristics of slope deposits in high tropical mountains (Cordillera Real, Bolivia)
  • Bolivia ; Geophysics ; Hydrology ; Moraine ; Mountain ; Slope ; Slope deposit ; Tracer ; Tropical zone
  • in slope deposits springs is monitored to estimate transfer velocities. The lag times estimated by the measurement of tracer velocity demonstrates that these slope deposits delayed the flow depending on the type of deposit. The delay is at least 24 h
  • Different transfer time measurements combined with morphometrical and sedimentological analysis were carried out on three talus slopes and two moraines during the rainy season. After injection of salt, the electrical conductivity of the water
  • in the case of the talus slopes and more than 48 h in the case of lateral moraines.
  • Recent research on the nature, origin and climatic relations of blocky and stratified slope deposits
  • Aeolian transport ; Bibliography ; Mass movement ; Mudflow ; Palaeo-environment ; Palaeoclimatology ; Periglacial features ; Slope ; Slope deposit ; Slope dynamics ; Stone river
  • to (coarse) blocky slopes and to scree accumulations, either on steep or gentle slopes. It is concluded that many deposits are formed by azonal processes, although their activity is often reltively high under periglacial conditions. Some of the deposits point
  • This paper summarizes knowledge of key processes and landforms that are found on slopes that show promise as indicators of past periglacial conditions. The review is restricted to the post-1985 period. Emphasis is on mass transfers related
  • Relict periglacial slope deposits in the Hex River Mountains, South Africa : observations and palaeoenvironmental implications
  • Cape Province ; Grain size distribution ; Lateglacial ; Mountain ; Palaeo-environment ; Periglacial features ; Slope deposit ; South Africa
  • The openwork block deposits in the Western Cape Mountains may have a variety of origins. However, some summit deposits appear to be periglacial blockfields and blockstreams and, as such, are probably the most widespread manifestation of cold Late
  • -Pleistocene conditions for this area. The morphometric and sedimentology of openwork boulder deposits at Matroosberg are described and evaluated here in terms of their palaeoclimatic significance.
  • Scree slope deposits during a cold-damp climatic phase in the early Middle Ages in the Gulf of La Spezia (Liguria, Italy)
  • Climatic cooling ; Coastal environment ; Italy ; Landslide ; Liguria ; Middle Age ; Palaeoclimatology ; Slope ; Slope deposit
  • In this paper, the AA. wish to indicate the localization of a scree slope in correspondence with the coast of the eastern promontory of the Gulf of La Spezia, whose formation, on the basis of its fabric features, of the age provided by a wood sample
  • enclosed within it and of the geometrical relations with a landslide body, provides interesting informations as paleogeographic and paleoclimatic as on the slope evolution within this part of the Eastern Liguria. - (NF)
  • Features of Middle Pleistocene sandur deposits in the Netherlands
  • The sandur deposits discussed below appear to be much similar to alluvial fan deposits. Only minor differences may occur which are related to the nature of the source area (slopes, availability of non-consolidated material) and to climatic
  • conditions. In the introduction a synopsis is given concerning river types and their deposits in general, represented in the deposits of this part of the North Sea Basin| subsequently, Neogene and Quaternary fluvial deposits (including sandur deposits
  • ) in The Netherlands are classified based on the type of deposition. (AIS).
  • Depositional origin of an adverse delta surface slope at Altermarka, northern Norway
  • Delta ; Glacial deposit ; Grain size distribution ; Norway ; Slope ; Slope deposit ; Soil ; Stratigraphy
  • Periglacial slope deposits and landforms in a Hungarian mountain of volcanic origin in Environmental and dynamic geomorphology.
  • The early Pleistocene development of an almost 2 km long slope is reconstructed in the Tokaj Mountains, NE-Hungary. The variety of periglacial forms and geomorphic processes are described for the four distinct segments of the slope. (DLO).
  • Facies and microfacies of slope deposits
  • Alps (The) ; Andes ; Biogenic process ; Bolivia ; France ; Freeze-thaw cycle ; Landslide ; Mass movement ; Micromorphology ; Mudflow ; Periglacial features ; Pleistocene ; Present time ; Sedimentology ; Slope ; Slope deposit ; Solifluction
  • This paper presents a comparative review of the sedimentological characteristics that typify the main slope mechanisms with a special reference to micromorphology. Results have been obtained from modern slope deposits from the French Alps
  • , the Bolivian Andes, southwestern France and Morocco, Pleistocene deposits from southwestern France and Portugal.
  • Block and debris deposits in the high Drakensberg, Lesotho, Southern Africa : implications for high altitude slope processes
  • Climatic variation ; Lesotho ; Mountain ; Mudflow ; Palaeo-environment ; Periglacial features ; Quaternary ; Rock glacier ; Slope deposit ; Slope dynamics ; Solifluction ; South Africa
  • This study describes the morphology and discusses the likely palaeogeomorphic processes of blockstreams and debris deposits on the Popple Peak and Njesuthi-Mafadi south-facing slopes in the Drakensberg. The geomorphic evidence provides much needed
  • information to help improve the understanding of south-facing slope processes during past colder periods. A model for high altitude Drakensberg south-facing slopes is presented and used to challenge and expand on recent models and ideas on southern African
  • Periglacial slope deposits in Carlisle's Hoek, near Rhodes, Eastern Cape Province
  • Tephrochronological study of slope deposits in the northwestern Kitakami mountains
  • The chronology of Upper Pleistocene stratified slope-waste deposits in Central Italy
  • Alluvium ; C 14 dating ; Geochronology ; Italy ; Marche (Italy) ; Pleistocene ; Quaternary ; Rill wash ; Slope ; Slope deposit ; Umbria
  • A stratigraphy of slope deposits and soils in the Northeastern Great Basin and its vicinity
  • Great Basin ; Loess ; Pedogenesis ; Slope ; Slope deposit ; Soil ; Stratigraphy ; United States
  • Origin of the red earth and gravel deposits in Nankou piedmont, northwestern Beijing, China
  • Beijing ; Chemical erosion ; China ; Clay mineral ; Geochemistry ; Microstructure ; Mudflow ; Palaeo-environment ; Palaeoclimate ; Palaeogeomorphology ; Piedmont ; Slope deposit
  • Analytic results of the mechanical and chemical composition, clay minerals, sedimentary structures and microtextures of the read earth and gravel deposits in Nankou piedmont, northwestern Beijing, China, suggest that the deposits have nothing to do
  • with glaciation but are palaeodebris-flow deposits. During the period of their deposition, the climate was humid and hot with plentiful rainfall, and oxidation, physical and chemical weathering were rather intense.
  • Conditions of formation of stratified screes, Slims River valley, Yukon Territory : a possible analogue with some deposits from Belgium
  • Belgium ; Canada ; Cold area ; Comparative study ; Grain size distribution ; Mudflow ; Palaeo-environment ; Palaeoclimate ; Pleistocene ; Slope ; Slope deposit ; Stratified scree ; Temperate zone ; Yukon Territory
  • Stratified scree is forming on 34-45° north-facing slopes in gullies in the Kluane Lake area of the St. Elias Range of the Yukon Territory. A remarkably similar Pleistocene deposit occurs at Noiseux in Belgium. Detailed examination of the deposits
  • from the Ykon and Noiseux shows that they have essentially similar characteristics, suggesting that the main deposit at Noiseux formed in the same way from frost-shattered Famenne siltstone with small quantities of loess. The deposit remaining today
  • Evolution of desert colluvial boulder slopes
  • Arid area ; California ; Dating ; Desert ; Geomorphometry ; Isotope dating ; Pleistocene ; Slope deposit ; Slope dynamics ; Slope gradient ; United States of America
  • The AA. employed rhyolite domes formed during the past million years in eastern California to study the evolution of boulder-dominated slopes. The slopes studied are steep and are made of coarse, boulder-sized blocks. These slopes include well
  • -varnished vertically-oriented colluvial deposits that appear similar to relict periglacial stone stripes. Basic field and isotopic dating methods are combined with 2 relatively new surface dating techniques, cosmogenic chlorine-36 and rock varnish
  • microlaminae, to produce a detailed million-year-long slope development history with broad implications for geomorphic theory.