The granite area of Bohuslän is characterised by an abundance of rockbasins of different sizes. These basins were measured, described and classified from air-photos according to their length, width, area, altitude, shape, boundaries, openness
of the basins. The AA. also aim to discriminate between glacial and non-glacial component in rockbasin development and to demonstrate the degree of rock control upon morphology in the formerly glaciated area.
and relation to joint configuration. The depth of basins was collected from digital elevation data. The patterns and characteristics of the bassins suggest that deep selective weathering had been the primary process involved in the origin and evolution
Discharge and sediment-load characteristics of the Hilda rock-glacier stream, Canadian Rocky Mountains, Alberta
as a buffering factor in basin runoff as compared with a similar glacierized basin. In addition, the rock glacier acts conservatively in sediment release from the basin and promotes denudation by dissolution and material transport as dissolved load.
Water discharge and sediment load characteristics of the Hilda rock-glacier stream are described for portions of the 1985 and 1986 ablation seasons. The hydrological behavior of the Hilda rock-glacier stream suggests that the rock glacier acts
Structural control of the morphometry of open rockbasins, Kananaskis region, Canadian Rocky Mountains
Bassin rocheux ; Canada ; Concept ; Dynamique de versant ; Géomorphologie structurale ; Géomorphométrie ; Modèle numérique ; Montagne ; Mouvement de masse ; Pente de versant ; Rocky Mountains ; Structure géologique ; Versant
rockbasins. The basins were classified structurally according to the relative orientations of bedding planes and the rock slopes. The optimal structure for large compact rockbasins is anaclinal, and the least favourable is cataclinal dip-overdip
Karst processes and phenomena in the perennially frozen carbonate rocks of the Middle Lena River Basin
Asian part of Russia ; Carbonate rock ; Cold area ; Karst ; Karstification ; Permafrost ; Sakha ; Thermal regime
Various karst processes and karst phenomena at scales from the macro to the micro occur in the cryolithozone of the middle Lena River basin. Karst processes have a warming impact on the enclosing perennially cryotic rocks and favour the formation
The AA. present evidence for multiple late Quaternary paleofloods in Arthurs Rock Gulch, a small ephemeral drainage basin in the Colorado Front Range foothills near Fort Collins, Colorado; and describe their approach to paleoflood retrodiction
Confirmation pétrographique et géochimique de la formation du bassin Lau (à l'ouest des Tonga) par expansion océanique affectant un ancien arc insulaire. (JRV).
Terrain analysis of the Racetrack basin and the sliding rocks of Death Valley
Arid area ; California ; El Niño ; Geographical information system ; Geomorphometry ; Quaternary ; Slide rocks ; United States of America ; Wind speed ; Years 1990-99
The Racetrack Playa's unusual surface features known as sliding rocks have been the subject of an ongoing debate and several mapping projects for half a century, although the causative mechanism remains unresolved. In 1996, the AA. generated
the first complete map of all observed sliding rock trails by submeter differential Global Positioning System (DGPS) mapping technology. Follow-up surveys in 1998 and 1999 revealed little modification of the 1996 sliding rock configuration. Only 4 rocks were
Spatial distribution of surface rock fragments along catenas in semiarid Arizona and Nevada, USA
Rock fragments in soil: surface dynamics
Arizona ; Bassin-versant ; Catena ; Domaine semi-aride ; Erosion des sols ; Etats-Unis ; Fragment de roche ; Modèle ; Nevada ; Pente de versant ; Prévision ; Roche ; Sol
Arizona ; Catena ; Forecast ; Model ; Nevada ; Rock ; Semi-arid area ; Slope gradient ; Soil ; Soil erosion ; United States ; Watershed
The major objectives of this study are to determine if a slope gradient-surface rock fragment cover relation exists on various catenas of semiarid Arizona and develop an equation to describe this relation.
Analyse multivariée ; Bassin-versant ; Erosion des sols ; Flysch ; Géographie physique ; Lithologie ; Molasse ; Roumanie ; Réseau de drainage ; Statistique ; Transport sédimentaire
To develop a multiple regression model the AA. took 99 small catchments (A
factors. The equations were applied to the Putna river basin, the AA. identified 274 third order drainage basins (Strahler's system) and for each basin they determined the sediment yield.
Sediment yield from some third order basins on the basement complex rocks in southwestern Nigeria
Altération chimique ; Bassin-versant ; Capacité de charge ; Géographie physique ; Nigéria ; Zone intertropicale
Dissolved sediment yield is greater than suspended sediment yield in almost all the basins and with a ratio varying from 0.7 to 6.8. This may show that the dominant geomorphological process in this environment is chemical rather than mechanical
erosion or that factors such as the nature of the farming system exist which inhibit the delivery of suspended sediments obtained from basin slopes to river channels.
Field-scale estimation of the volume percentage of rock fragments in stony soils by electrical resistivity
Bassin parisien ; Beauce ; Electrical resistivity ; France ; Geophysics ; Model ; Quantitative analysis ; Rock fragment ; Soil ; Soil properties ; Soil water ; Stony soil
Analyse quantitative ; Bassin parisien ; Beauce ; Eau du sol ; Fragment de roche ; France ; Géophysique ; Modèle ; Propriétés du sol ; Résistivité électrique ; Sol ; Sol pierreux
This paper presents a method that uses field spatial electrical resistivity measurements to determine the volume proportion of rock fragments. Based on the hypothesis that the electrical resistivity signal noise increases as the proportion of rock
fragments increases, a model was developed that uses the standard deviation of the apparent electrical resistivity measurements over a small area as an indicator of rock fragment contents. The model was tested on 3 study areas of several hectares containing
soil units with varying quantities of rock fragments in the Beauce region (Villamblain, France). The developed model strongly depends on the water content in the soil and the rock type and must be calibrated in each context. Nevertheless, estimations
of the rock fragment content in stony soils can be performed efficiently in the surface horizon as well as all along the soil profile.
Newly acquired data from the Blue Nile Valley in the Sudan indicate that the early sediments of the river system were deposited in structurally controlled basins during Tertiary and Quaternary times. Deposition is related to glacial and periglacial
activity in the Ethiopian Plateau. The sediments which represent braided channel deposits were derived from local basement complex rocks and volcanic rocks of the Ethiopian Plateau.
by non-carbonate crystalline metamorphic rock. Marble corrosion is caused primarily by the influx of allogenic waters from the non-carbonate part of the catchment. Hydrochemical measurements were made over the course of 8 years. The calculated denudation
An experiment in which the lichen Collema auriforma was subjected to a number of wetting-drying cycles, showed, using scanning electron microscopy, that contraction of the lichen thallus during the drying phase plucked rock fragments from
the substrate surface. This process could contribute to the formation of karstic features including solution basins.
Dissolved load budget of drainage basin systems on silicate rocks and land use in the Northern Eifel/Germany
Allemagne ; Bassin-versant ; Bilan sédimentaire ; Charge en solution ; Eifel ; Erosion des sols ; Hydrochimie ; Qualité de l'eau ; Utilisation du sol
The purpose of this paper is to estimate the influence of the land use and the water balance on the dissolved load budget in drainage basins on silicate rocks. The water balance in the Hohes Venn and the Rureifel areas is mainly influenced
Morphological and morphometric analyses of drumlin bedforms in the Omagh Basin, North Central Ireland
The aim of this paper is to describe and compare the morphology and morphometry of diamict-dominated and rock-cored drumlins in the Omagh Basin. Diamict drumlins are mainly of classical or fused type and are found in lowland and basinal locations
. Rock-cored drumlins are more morphologically diverse and occur on high-level plateaus and upland flanks. Morphometric analysis reveals both spatial and statistically significant absolute differences between the elongation ratios and orientations
of diamict and rock-cored drumlins. This means drumlinization cannot be attributed to a single set of subglacial processes or a single time-interval.