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  • The role of debris supply conditions in predicting debris flow activity
  • Debris flow frequency and magnitude were determined for 33 basins in southwest British Columbia with a view to predicting debris flow activity.
  • A rational method for estimating maximum discharge of a landslide-induced debris flow : a case study from southwestern China
  • China ; Debris flow ; Discharge ; Forecast ; High mountain ; Landslide ; Methodology ; Mountain ; Natural hazards ; Sichuan ; Slope dynamics
  • Chine ; Coulée de débris ; Dynamique de versant ; Débit ; Débit maximum ; Glissement de terrain ; Haute montagne ; Montagne ; Méthodologie ; Prévision ; Risque naturel ; Sichuan
  • The proposed method was applied to an actual landslide-induced debris flow that occurred on June 13, 1995 in a high-altitude mountainous region of southwestern China. The method depends on field measurements of channel dimensions and some empirical
  • equations for debris flow dynamics. Maximum discharge is one of the most important characteristics of debris flows, because it can be used for assessing the hazard potential of debris flows and for developing preventive measures to reduce the dynamic impacts
  • of debris flows.
  • Debris flows involved in the development of Pleistocene stratified slope deposits in Periglacial processes and landforms.
  • Two approaches to this problem : 1) the analysis of recent debris flows within an Alpine environment, and 2) laboratory experiments, simulating debris flows under different conditions. Sedimentological characteristics of debris flow material
  • are discussed, as well as relationships between physical and sedimentological properties. Resulting criteria for the recognition of debris flow material are given and the role of temperature is treated briefly.
  • Debris flows as geomorphic agents in the Huachuca Mountains of southeastern Arizona
  • By examining evidence left by historical debris flows, which occured in 1988 and 1977, and debris-flow deposits dating back to the Pleistocene, the AA. were able to draw inferences about controls on debris-flow occurence and the geomorphic role
  • of debris flows in this semiarid mountain range.
  • The significance of trees and coarse woody debris in shaping the debris flow accumulation zone (North slope of the Babia Góra massif, Poland)
  • Debris flow ; Dendrochronology ; Geomorphological mapping ; Impact ; Mountain ; Poland ; Slope evolution ; Spruce ; Tree ; Tree line
  • Arbre ; Cartographie géomorphologique ; Coulée de débris ; Dendrochronologie ; Epicéa ; Evolution de versant ; Impact ; Limite supérieure de la forêt ; Montagne ; Pologne
  • Influence des arbres et des débris de bois grossiers sur les processus de transport et de dépôt dans la zone d'accumulation. Estimation de la durée pendant laquelle ces débris ont un impact sur les processus de versant.
  • The significance of channel recharge rates for estimating debris-flow magnitude and frequency
  • Bassin-versant ; British Columbia ; Canada ; Coulée de débris ; Dynamique de versant ; Littoral ; Prévision ; Risque naturel
  • This paper deals with the determination of debris recharge rates in debris-flow channels based on knowledge of debris storage and the elapsed time since the last debris flow. Data are obtained from coastal British Columbia and a relation is obtained
  • Ice flow vectors on the debris-mantled Tasman Glacier, 1957-1986
  • Glacial ablation ; Glacial flow ; Glacier ; Glaciology ; New Zealand ; Photogrammetry ; Shear stress ; South Island ; Thermokarst
  • This paper examines the debris-mantled zone of Tasman Glacier for evidence of debris mantle formation. Particularly, the velocity distribution and surface morphology are studied to understand the extent and rate of ice stagnation and the process
  • of debris mantling of the glacier surface.
  • Alpine debris flows triggered by a 28 July 1999 thunderstorm in the central Front Range, Colorado
  • Colorado ; Debris flow ; Front Range ; Gully erosion ; Landslide ; Mountain ; Precipitation ; Rainstorm ; Slope gradient ; Soil properties ; Topography ; United States of America
  • Colorado ; Coulée de débris ; Etats-Unis ; Front Range ; Glissement de terrain ; Montagne ; Orage ; Pente de versant ; Propriétés du sol ; Précipitation ; Ravinement ; Topographie
  • The AA. mapped the debris flows from color aerial photography and inspected many of them in the field. Three processes initiated debris flows : mobilization of shallow landslides in thick, often well vegetated, colluvium; transport of material
  • eroded from steep unvegetated hillslopes via a system of coalescing rills; the firehose effect which occurred where overland flow became concentrated in steep bedrock channels and scoured debris from talus deposits and the heads of debris fans. Based
  • on field observations and examination of soils mapping, the AA. identified a relation between the degree of soil development and the process type that generated debris flows.
  • Dynamics in debris-flow activity on a forested cone - A case study using different dendroecological approaches
  • Alps (The) ; Debris flow ; Dendrochronology ; Dendrology ; Mountain ; Slope dynamics ; Switzerland ; Twentieth Century
  • Alpes ; Coulée de débris ; Dendrochronologie ; Dendrogéomorphologie ; Dendrologie ; Dynamique de versant ; Montagne ; Siècle 20 ; Suisse
  • The aim of this study was to combine dendrogeomorphological analyses with an assessment of germination dates of successor trees in order to understand the dynamics of past debris-flow events on a forested cone in the Valais Alps, Switzerland
  • . As a consequence of the deeply incised channel and the stabilization measures undertaken along the banks, signs of debris flows are missing in the tree-ring record for the past two decades.
  • Fractality of grain composition of debris flows
  • 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
  • The 1987 debris flows in Switzerland: documentation and analysis
  • Alps (The) ; Catastrophe ; Debris flow ; Flood ; Mountain ; Slope ; Slope dynamics ; Slope gradient ; Switzerland
  • A great number of debris flows occurred during the flood catastrophes of the summer of 1987 in the Swiss Alps. Aerial photography, field investigations and eyewitness accounts documented and analysed the events. Apart from incision into weak bedrock
  • to estimate the most important flow parameters. These values are compared to debris flow data from Canada and Japan.
  • The influence of debris flows on channels and valley floors in the Oregon Coast Range, U.S.A.
  • The A. presents a field study of the erosional and depositional characteristics of debris flows and their influence on alluvial channels and valley floors.
  • Modeling of a debris flow from the Hrenovec torrential watershed above the village of Kropa
  • Debris flow ; Landslide ; Model ; Precipitation ; Slope dynamics ; Slope gradient ; Slovenia ; Watershed
  • Bassin-versant ; Coulée de débris ; Dynamique de versant ; Glissement de terrain ; Modèle ; Pente de versant ; Précipitation ; Slovénie
  • In this paper, debris-flow modeling is shown specifically on the basis of a potential debris flow from the Hrenovec torrential watershed above the village of Kropa in NW Slovenia. This site was chosen, because in this particular torrential watershed
  • a small surficial landslide turned into a debris flow during a storm on September 18, 2007. Using public available data on rainfall and topography, we developed two scenarios of debris-flow triggering with an estimated magnitude of 50.000 m3. - (L'A.).
  • A debris flow calendar derived from sediments of lake Lago di Braies (N. Italy)
  • Alps (The) ; Comparative study ; Debris flow ; Dendrochronology ; Geochronology ; Holocene ; Italy ; Lacustrine sediment ; Lake ; Mountain ; Quaternary
  • Alpes ; Coulée de débris ; Dendrochronologie ; Etude comparée ; Géochronologie ; Holocène ; Italie ; Lac ; Montagne ; Quaternaire ; Sédiment lacustre
  • In this study lake sediments were used for developing a high resolution calendar of past debris flow events. The fine grained material of debris flows is flushed into the lake. This material forms characteristic layers in the lake sediments, which
  • are different from the typical annual lamination. By analysing thin sections of sediment, debris flow events of the last 2250 years were reconstructed with an annual resolution. Since debris flow frequency varies strongly, periods with high and low frequencies
  • Impact of small amounts of swelling clays on the physical properties of debris-flow-like granular materials. Implications for the study of alpine debris flow
  • Alps (The) ; Clay ; Debris flow ; Grain size distribution ; Model ; Mountain ; Shear stress ; Slope ; Soil ; Soil properties ; Switzerland
  • Alpes ; Argile ; Contrainte de cisaillement ; Coulée de débris ; Granulométrie ; Modèle ; Montagne ; Propriétés du sol ; Sol ; Suisse ; Versant
  • The aim of this study is to test whether a small content of swelling clay may have a significant impact on the rheology of a reconstituted debris-flow-like material. This has been carried out by using a well characterized mixture that simulates
  • the grain size distribution and composition of alpine debris flows up to 20 mm. The fraction of swelling clay was then varied and the rheological properties of the mixture tested using a large volume rheometer and a plate-plate geometry for the fine fraction.
  • Hazard assessment of potential periglacial debris flows based on GIS-based spatial modelling and geophysical field surveys : a case study in the Swiss Alps
  • Active layer ; Alps (The) ; Debris flow ; Geographical information system ; Geophysics ; Moraine ; Mountain ; Natural hazards ; Periglacial features ; Permafrost ; Switzerland
  • Alpes ; Coulée de débris ; Géophysique ; Mollisol ; Montagne ; Moraine ; Pergélisol ; Périglaciaire ; Risque naturel ; Suisse ; Système d'information géographique
  • In a potential debris flow-starting zone in the Upper Engadine (moraine/debris rock glacier complex Boval) two-dimensional electrical resistivity surveys were used to detect the presence/absence of permafrost and to estimate active-layer depth
  • . The results show that the moraine complex represents a periglacial debris reservoir which consists of frozen and unfrozen debris. The ice-bonded part of the moraine is largely protected from sudden destabilisation and retrogressive erosion can be assumed
  • to be limited. However, future degradation or loss of permafrost in the lower parts of the debris rock glacier would increase the amount of erodible debris and reduce mechanical stability.
  • Estimation of magnitudes of debris flows in selected torrential watersheds in Slovenia
  • Debris flow ; Geomorphology ; Morphometry ; Slovenia ; Torrent ; Watershed
  • Bassin-versant ; Coulée de débris ; Géomorphologie ; Morphométrie ; Slovénie ; Torrent
  • In this paper the application of different methods for estimation of magnitudes of rainfall-induced debris flows in 18 torrents in the upper Sava River valley, NW Slovenia, and in 2 torrents in Pohorje, N Slovenia is described. Additional
  • verification of the methods was performed in the torrential watersheds with active debris flows in the recent past (Predelica and Brusnik in the Soča River basin, W Slovenia). For some of the methods, the knowledge of morphometric characteristics
  • of a torrential watershed, torrential channel and torrential fan is enough. For other methods, a mathematical tool (HEC-HMS) had to be applied in order to develop a hydrologic run-off model of precipitation that can trigger debris flows. Computed debris-flow
  • groups with regard to the debris-flow hazard : debris-flow with low possibility). A limit between debris-flow fans and torrential fans is proposed : Melton number 0.3 and torrential fan gradient 4°, that is 7%. Out of 24 investigated torrential fans, 13
  • fans were classified into the group of debris-flow fans, 5 fans were classified into the group of torrential fans, and the rest 6 fans were classified into the group of transitional fans. - (IKR)
  • Factors affecting sedimentary outflow from talus slope by debris flow : a laboratory experiment
  • Alluvial cone ; Cliff ; Debris flow ; Experimentation ; Japan ; Precipitation ; Sediment transport ; Slope ; Slope dynamics ; Slope gradient
  • Coulée de débris ; Cône de déjection ; Dynamique de versant ; Expérimentation ; Falaise ; Japon ; Pente de versant ; Précipitation ; Transport sédimentaire ; Versant
  • To examine running distance of debris flows occurring on the talus slopes, rainfall experiments were carried out. The quantity Vt is defined as the reciprocal of the threshold value of Lc/Lt at which debris flows just reach the bottom of the talus
  • slope, where Lc is the horizontal length of the cliff and Lt is the horizontal length of the talus slope. The value of Vt is also a measure of the possibility of sedimentary outflow from the talus slope by debris flow. The value of Vt shows strong
  • correlation with the hydraulic conductivity of talus sediment (K) and the rainfall intensity (It). The outflow of debris from the talus slope can be predicted using the values of Lc, Lt, K, and It.
  • Quartz-grain surfaces of debris flow material in the marginal mountains of Tibet
  • China ; Debris flow ; Glacial features ; Microstructure ; Mountain ; Palaeo-environment ; Quartz ; Sand ; Slope dynamics ; Tibet
  • This study is an attempt to establish the relationship between morphoscopic surface features of quartz-grains and the dynamic processes of debris flows. More specifically, it is aimed at distinguishing between quartz-grain surface characteristics
  • of debris flow and of glacial sands.
  • Lichenometrical studies and dating of debris flow deposits in the High Tatra Mountains, Poland
  • Dating ; Debris flows ; Holocene ; Lichenometry ; Little ice age ; Paleogeography ; Poland ; Quaternary ; Tatra Mountains
  • of the investigated debris flows were triggered during the later part of the Little Ice Age, due to alluviation. During the last hundred years, only a few debris flows have occurred.