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  • The aeolian dust accumulation curve
  • Aeolian deposit ; Aeolian dust ; Aeolian features ; Belgium ; Concept ; Experimentation ; Flanders ; Leuven ; Model ; Wind erosion ; Wind speed
  • This article presents a simple physical concept of aeolian dust accumulation, based on the behaviour of the subprocesses of dust deposition and dust erosion. A model is tested in a series of wind tunnel experiments. Some implications of the model
  • Aeolian deposition of dust over hills : the effect of dust grain size on the deposition pattern
  • Aeolian dust ; Aeolian features ; Aeolian transport ; Belgium ; Experimentation ; Flemish Brabant ; Grain size distribution ; Impact ; Leuven ; Topography
  • Wind tunnel experiments were conducted to investigate the effects of topography on the grain size characteristics of aeolian dust deposits. Experiments were performed on 3 isolated hills having various size and aspect ratios. The longitudinal
  • profile of the median grain diameter was investigated for each hill. The wind tunnel experiments show that the grain size characteristics of aeolian dust deposits are affected by topography.
  • Aeolian dust contributions to soil on the Namoi Valley, northern NSW, Australia
  • Aeolian dust ; Aeolian features ; Alluvium ; Australia ; Geochemistry ; Grain size distribution ; Mineralogy ; New South Wales ; Pedogenesis ; Soil
  • The presence of aeolian dust in soil profiles can easily be obscured by pedoturbation , especially in clay soils with vertic properties, such as those of northern New South Wales. To indicate aeolian dust components within soil profiles typical
  • of the lower Namoi River Valley, the AA. used a range of granulometric, mineralogical and geochemical methods. The AA. also examined contemporary data on dust deposition rates and compared characteristics of present-day dust with the soil materials.
  • Effect of rock fragment embedding on the aeolian deposition of dust on stone-covered surfaces
  • Aeolian dust ; Aeolian features ; Belgium ; Experimentation ; Grain size distribution ; Pebbles ; Spatial distribution ; Wind speed
  • This study investigates how the deposition of dust is affected when rock fragments become gradually more embedded in the ground or, inversely, become more concentrated on the surface. Experiments were executed in an aeolian dust wind tunnel with 8
  • different types of pebbles. Aerodynamic flow separation and diverging and converging airflow play an important role in the process of dust deposition on stone-covered surfaces.
  • Effect of rock fragment eccentricity on eolian deposition of atmospheric dust
  • Aeolian dust ; Aeolian features ; Belgium ; Experimentation ; Geomorphometry ; Loess ; Wind speed
  • The aim of this study is to investigate the physical effects of rock fragment eccentricity on the dust deposition mechanism. This was examined in a wind tunnel. All data in this study refer to intial dust deposition (not accumulation), since only
  • wind velocities below the dust deflation threshold were tested.
  • Harmattan dust deposition and particle size in Ghana
  • Aeolian dust ; Aeolian features ; Agropedology ; Arid area ; Ghana ; Grain size distribution ; Loess ; Research technique ; Sampling ; Sediment transport
  • This paper describes the development of sampling techniques for monitoring the Harmattan dust deposition in Ghana. It compares 3 different methods to trap the Harmattan dust and describes the difference in amount and particle size distribution
  • of dust trapped in various agroecological zones.
  • Particle-size analysis of aeolian dusts, soils and sediments in very small quantities using a Coulter Multisizer
  • Aeolian dust ; Grain size distribution ; Methodology ; Reliability ; Sedimentology ; Soil
  • This paper evaluates the Coulter Multisizer for sizing soils, aeolian dusts and other sediments which are only available in small quantities.
  • Comparison of magnetic particles in airborne dust on Mars and in the Harmattan dust from south of Sahara
  • Aeolian dust ; Aeolian features ; Comparative study ; Ghana ; Mars planet ; Mineralogy
  • The magnetic properties experiments on the Mars Pathfinder mission indicate that Martian airborne dust is slightly magnetic. For purposes of comparison similar experiments on the magnetic properties of terrestrial airborne dust on the Earth have
  • been performed at the University of Ghana. The main result of these experiments is that the airborne Harmattan dust in Ghana is substantially less magnetic than the dust suspended in the Martian atmosphere.
  • Addition of aeolian dusts to soils in southeastern Australia : red silty clay trapped in dunes bordering Murrumbidgee River in the Wagga Wagga region
  • Aeolian dust ; Aeolian features ; Australia ; Clay mineral ; Climatic variation ; Dating ; Dune ; Grain size distribution ; New South Wales ; Palaeoclimate ; Quaternary ; Soil ; Soil properties
  • In southeastern Australia, aeolian dust deposits are very common and have a significant influence on soil properties and soil landscapes. However, the characteristics of the pure dust materials and the rates of dust-fall in the past are unclear
  • because of the low overall rate of dust deposition and mixing with locally derived sediments. In the Wagga Wagga region, some dunes have functioned as dust traps, and so provide an opportunity for characterising relatively pure dust deposits and evaluating
  • past dust deposition rates. Results and discussion.
  • Saharan dust : sources and trajectories
  • Aeolian dust ; Aeolian features ; Aeolian transport ; Aerosol ; Africa ; Atmosphere ; Atmospheric circulation ; Cartography ; Desert ; Remote sensing ; Sahara
  • The Sahara is the world's largest source of aeolian desert dust, but precise information on specific sources of this material is poor. This paper uses daily data from the Total Ozone Mapping Spectrometer (TOMS) for 1999 to identify source areas
  • for major dust events and their trajectories of long-range transport. Two major sources areas are identified : the Bodélé depression and an area covering eastern Mauritania, western Mali and southern Algeria. Both of these major dust sources are primarily
  • Wind tunnel experiments and field measurements of aeolian dust deposition on conical hills
  • Aeolian features ; Aeolian transport ; Arid area ; Desert ; Experimentation ; Hill ; Israel ; Negev ; Topography
  • The spatial pattern of short-term aeolian dust deposition on and around cone-shaped hills is investigated via the simulation, in a wind tunnel, of dust storms over a topographic scale model of a conical hill in the Negev desert, Israel. The results
  • are tested during a full-scale dust storm in the Negev.
  • Superposition of aeolian dust ripple patterns as a result of changing wind directions
  • Eolian dust ; Eolian features ; Experimentation ; Geomorphometry ; Ripple-marks ; Wind
  • The effect of a change of wind direction on the orientation (and some other morphometric characteristics) or aeolian dust ripples is investigated. Ripple formation is simulated in a wind tunnel on surfaces that are already characterized
  • Mineralogy of dust deposited during the Harmattan season in Ghana
  • Aeolian dust ; Aeolian features ; Aeolian transport ; Africa ; Clay mineral ; Geochemistry ; Ghana ; Mineralogy ; Sahara ; West Africa ; Wind
  • The AA. studied samples of dust and topsoils in various agroecological zones, from the north to the south of Ghana, focussing mainly on the mineralogy of these materials. Some data about grain sizes and morphology of the samples are also presented
  • . The relative contents of K-feldspars and plagioclase vary markedly in the different zones. The pH of the dust is significantly higher than that of the local soils, indicating that a substantial amount of the dust comes from the Sahara.
  • Dust deposition and particle size in Mali, West Africa
  • Aeolian dust ; Aeolian features ; Atmospheric circulation ; Grain size distribution ; Mali ; Season ; Soil properties ; Wind
  • This paper describes dust deposition processes in Mali, West Africa, during April and May 1990, and examines the relative contributions of dusts from local, regional and more distant sources using dust particle size data. The significance
  • of these results for studies of dust contributions to soils is discussed.
  • Pathways of dust input to the Chinese Loess Plateau during the last glacial and interglacial periods
  • Aeolian features ; Aeolian transport ; China ; Lateglacial ; Loess ; Palaeogeography ; Palaeomagnetism ; Palaeosol ; Plateau ; Quaternary ; Spatial distribution
  • In this study, 32 loess-paleosol profiles of the last glacial and interglacial periods were measured for magnetic susceptibility in order to investigate the dust transport pathways of dust input to the Loess Plateau. Because sedimentation rates
  • decrease downwind from the dust source, the spatial distribution of dust sedimentation rates shows that northwest and west winds were the 2 most important agents for transport of dust to the Loess Plateau during the last glacial cycle.
  • Aeolian dust transport and deposition by foehn winds in an alpine environment, Lake Tekapo, New Zealand
  • Aeolian features ; Aeolian transport ; Dust storm ; Erodibility ; Foehn ; Lacustrine basin ; Mountain ; New Zealand ; South Island ; Topography ; Wind erosion ; Wind speed
  • throughout the study indicate that foehn windstorms provide ideal conditions for the initiation of aeolian processes, including dust storm genesis. Potential dust roses were determined for 2 sites within the lake basin.
  • Observation from an automatic weather station and anemograph network are used in conjunction with recorded dust deposition rates to identify principle sources of wind blown dust within an alpine lake basin. Meteorological observations made
  • Quantitative estimates of the effect of climate change on dust storm activity in Australia during the Last Glacial Maximum
  • Special Issue. Response of aeolian processes to global change
  • Aeolian features ; Aeolian transport ; Australia ; Climatic variation ; Dust storm ; Global change ; Lateglacial ; Quaternary ; Spatial variation
  • Quantitative estimates are made of the effect of climate change upon dust activity during the Last Glacial Maximum (LGM), which peaked 18,000 years ago, using present-day measurements of the occurence of dust storms recalculated in the light
  • of information on LGM climatic change. Dust storm seasons were lengthened and dust paths were modified. Estimates based upon climate alone, without considering the increased supplies of sediment to dust source areas during the LGM, however, probably underestimate
  • LGM dust activity.
  • Dry aeolian dust accumulation in rocky deserts : a medium-term field experiments based on short-term wind tunnel simulations
  • Aeolian dust ; Aeolian features ; Arid area ; Desert ; Erosion ; Field experiment ; Geomorphometry ; Israel ; Negev ; Spatial distribution
  • The A. explore the possibilities of using short-term wind tunnel simulations for the prediction of medium-term dust accumulation. The pattern of aeolian dust deposition and aeolian dust erosion created on a topographic scale model of a hilly desert
  • Wind tunnel experiments of aeolian dust deposition along ranges of hills
  • Aeolian features ; Belgium ; Experimentation ; Hill ; Loess ; Slope gradient ; Topography ; Wind ; Wind erosion
  • The aim of this paper is to study dust deposition patterns over various topographic configurations. Dust patterns are analysed for different combinations of hill size and hill spacing, and comparisons are made with the reference profiles over
  • in dust deposition and accumulation, the effects should be recognizable in the profiles.
  • Deposition rate of Saharan dust in the Aegean Sea
  • Aeolian dust ; Aeolian features ; Aeolian transport ; Atmospheric circulation ; Atmospheric dynamics ; Crete ; Greece ; Marine sediment ; Mediterranean Sea ; Sahara