Aquitaine ; Barchan ; C 14 dating ; Classification ; Coastal environment ; Dune ; France ; Geochronology ; Geomorphology ; Holocene ; Palaeosol
The coastal dune field of Aquitaine is one of the most extensive in Europe, which was fixed during the 19th century. This paper proposes a new chronology and a morphological classification for the dunesystems found in Médoc.
Aeolian dune field self-organization - implications for the formation of simple versus complex dune-field patterns
Auto-organisation ; Dune ; Eolien ; Géomorphologie littorale ; Simulation par ordinateur ; Système complexe
Aeolian features ; Coastal geomorphology ; Dune ; Self-organizing behaviour
Les dunes et les champs de dunes comme systèmes complexes. Implications pour les types de champs de dunes simples et complexes. Les variations à l'intérieur de types de dunes simples. Les surfaces géomorphologiques et les archives de roches.
Geological and palynological investigations of two main dunesystems west of Nieuwpoort. The Old Dunesystem is believed to be older than 4300 B.P. The Young Dune area has a complex history: older dunes (2800-900 B.P.) underneath the Young Dune
system: a subphase 11-14 th century A.D.| a subphase starting at the end of the 14th century (large parabolic dunes burying the former landscape).
Nearest neighbor methods applied to dune field organization : the Coral Pink Sand Dunes, Utah, USA
Analyse de voisinage ; Dune ; Eolien ; Etats-Unis ; Géomorphologie ; Photographie aérienne ; Système d'information géographique ; Technique de recherche ; Utah
Aeolian features ; Aerial photography ; Dune ; Geographical information system ; Geomorphology ; Research technique ; United States of America ; Utah
Using the Coral Pink Sand Dunes in southern Utah as a model, this study tests nearest neighbor analysis adapted as a method to objectively identify and characterize differences in two dimensional dune patterns within a dune field and to identify
changes in dune patterns over time. Reducing transverse and barchanoid dunes from linear to three-point features in planar space emphasizes the clustering that occurs when dune lengths and wave lengths are more disorganized or random. This clustering may
be in response to a system perturbation, such as an influx of sediment, and is reflected in lower nearest neighbor index values.
Aeolian features ; Aeolian transport ; Arid area ; Botswana ; Desert ; Dune ; Plant cover ; Wind erosion
The aims of this study are: first, to establish the level of sediment transport acivity on linear dunes in the southwest Kalahari, and secondly, to identify the role of vegetation in the dynamics of the dunesystem.
Analyse statistique ; Auto-organisation ; California ; Domaine aride ; Dune ; Eolien ; Etats-Unis ; Géomorphométrie ; Mauritanie ; Namibie ; New Mexico ; Système
Aeolian features ; Arid area ; California ; Dune ; Geomorphometry ; Mauritania ; Namibia ; New Mexico ; Self-organizing behaviour ; Statistical analysis ; System ; United States of America
, the Agneitir in Mauritania, and the Namib in Namibia. The results are consistent with models of dune fields as self-organizing complex systems in which a characteristic pattern emerges as a function of constructional time.
As a basic form of pattern analysis, the parameters of dune spacing, defect density, crest orientation and crest length are measured from remote images and treated statistically for dunes at White Sands in New Mexico, the Algodones in California
from topographic methods (total station and GPS), and second, the quantification of the displacement of the dunesystem. The analysis of the correspondence between the movement of different parts of the dune and the influence of the intensity
This work analyses the viability of photogrammetry for the determination of the spatial-temporal changes of a coastal parabolic dune. Two factors have been analysed : first, the comparison of the photogrammetric results with the results obtained
and direction of the prevailing wind in the area is also desired. The dune advanced and the partial implications for the dynamic of human modified processes on the natural park have been established.
A mathematical model of the hydrogeological system of the dune area of De Panne is presented, dealing with the saturated and unsaturated zones. The hydrochemistry of the aquifer has been investigated by chemical analyses and geoelectrical well
Aeolian features ; Aeolian transport ; Arid area ; Barchan ; Colorado ; Drought ; Dune ; Geographical information system ; Satellite imagery ; Twentieth Century ; United States of America
To evaluate the response of the active parabolic and barchanoid dunes, a time series of remote sensed images from 1936 to 1999 is studied, using image analysis and Geographic Information System (GIS) techniques and complemented wih field assessment
. The extent of dune migration is evaluated with respect to climate parameters like precipitation and Palmer Drought Severity Index (PDSI) to better understand the landscape response to varying drought in the twentieth century. This contribution provides
insight into how semiarid landscapes respond to drought and quantifies thresholds and rates for dune migration at the Great Sand Dunes National Park and Preserve.
Recent stabilization of active sand dunes on the Canadian prairies and relation to recent climate variations
Canada ; Colonisation végétale ; Dune ; Eolien ; Manitoba ; Photographie aérienne ; Saskatchewan ; Système d'information géographique ; Transport éolien ; Variabilité climatique ; Vitesse du vent
Aeolian features ; Aeolian transport ; Aerial photography ; Canada ; Climatic variability ; Dune ; Geographical information system ; Manitoba ; Plant colonization ; Saskatchewan ; Wind speed
Changes in dune activity were determined from historical aerial photographs at 7 sites with active parabolic dunes in Saskatchewan and Manitoba. The methodology developed combines digital image processing and geographical information system (GIS
) analysis to measure changes in dune activity from the aerial photographs, as well as correlation analysis to determine the relation between dune activity and climate variations. Overall, dune activity has been decreasing since the early to mid 1900s
as evidenced by greater vegetation colonization than sand dune migration or reactivation.
Aeolian features ; Digital elevation model ; Dune ; Geographical information system ; Geomorphometry ; Lake ; Michigan ; Sand ; United States of America
This study assesses the geography and volume of coastal dune sand along Lakes Huron and Michigan in Lower Michigan. Dune field extents were obtained from digital maps of critical dune area and soil parent material. Volumetric estimates were
determined by establishing basal surface elevations and then calculating the average height of overlying dune deposits using digital elevation model (DEM) data within a raster GIS framework. Results and discussion.
Cette image de SEASAT couvre la majeure partie du champ de dunes de Sonora. Les différentes structures éoliennes y apparaissent en clair parce que les surfaces lisses sans végétation des dunes réfléchissent spéculairement l'énergie du radar.
Reconnaissance thermoluminescence dating of northern Australian coastal dunesystems
Australie ; Datation ; Datation C 14 ; Dune ; Géographie physique ; Littoral ; Northern Australia ; Paléo-environnement ; Quaternaire ; Thermoluminescence ; Zone intertropicale
Quaternary lithostratigraphic units in coastal dunes have been dated at three locations in northern Australia, Cobourg Peninsula, Shelburne Bay, and Cape Flattery, by both radiocarbon dating of shell and organic carbon and thermoluminescence (TL
) sediment dating. Seventeen TL dates were measured. None of the TL dates contradict the ages given by radiocarbon. Older dune deposits have also been dated to address the wider problem of the episodic nature of dune emplacement.
Coastal dunes of Ontario: distribution and geomorphology
Canada ; Dune ; Great Lakes ; Géographie de l'Amérique ; Géomorphogenèse ; Holocène ; Littoral ; Ontario ; Quaternaire zones moyennes ; Système dunaire
On trouve en Ontario des dunes transversales, des dunes paraboliques et quelques dunes perchées au sommet de falaises. Plusieurs complexes dunaires sont aujourd'hui isolés du rivage et se rencontrent sur des plaines sableuses correspondant au fond
de paléo-lacs et mers du Quaternaire wisconsinien. D'autres correspondent à des systèmes littoraux développés aux différents niveaux occupés jadis par les eaux des Grands Lacs.
Bilan sédimentaire ; Concept ; Dune ; Eolien ; Géomorphodynamique ; Littoral ; Modèle ; Transport sédimentaire
Aeolian features ; Coastal environment ; Concept ; Dune ; Earth surface processes ; Model ; Sediment budget ; Sediment transport
. Nine characteristic environments comprise the beach and dune sediment-budget ensemble, representing a classification scheme for reciprocating coastal systems.
At all scales, there are potential suites of interaction between system forms and processes, and thhe mechanisms of interaction are stressed in this article. At micro-scales, this interaction is formalized through the concept of morphodynamics
Dune pattern statistics applied to the Kalahari Dune Desert, Southern Africa
Afrique du Sud ; Domaine aride ; Dune ; Désert ; Erg ; Géographie physique ; Géomorphodynamique ; Kalahari ; Statistique ; Système dunaire
Des dunes linéaires dans le désert du Kalahari forment une série de systèmes de dunes stabilisées dans le Mega Kalahari et ont été signalées par Goudie (1969) comme obéissant à la loi de Horton de l'ordre des affluents. Utilisant la méthode
d'analyse statistique de Mabbutt et Wooding (1983) un argument est présenté qui suggère qu'un équilibre dynamique était achevé localement dans le système entre la géométrie du réseau de dunes et les facteurs de l'environnement avant que l'erg soit stabilisé.
Chine ; Distribution spatiale ; Dune ; Dune littorale ; Désert ; Eolien ; Géomorphogenèse ; Géomorphométrie ; Lutte contre l'érosion ; Modèle numérique ; Monde
Aeolian features ; China ; Coastal dune ; Desert ; Dune ; Erosion control ; Geomorphogenesis ; Geomorphometry ; Numerical model ; Spatial distribution ; World
and environmental studies. It embraces all types of dune, terrestrial and in the Solar System, in deserts, on coasts, and in the past. It incorporates research findings to come out of China, where the field is expanding most rapidly. Discusses the most recent range
This book discusses the shapes, sizes, patterns, distribution, history and care of wind-blown dunes. It is the first English-language book in over a decade to incorporate the latest research in this active and fast-developing field of geomorphology
of skills and technology now focused on the study of dunes. Latest ideas from numerical modelling and field studies are included and are illustrated by maps, diagrams and photographs, and supported by an extensive bibliography. – (HC)
Antiquity ; Archaeology ; Bay ; Brittany ; Coastal dune ; Coastal environment ; Dating ; Finistère ; France ; Geochronology ; Holocene ; Isotope dating ; Palaeo-environment ; Prehistory ; Protohistory ; Sea level ; Sedimentology
Le sud de la baie d'Audierne présente un système complexe de dunes littorales holocènes successives, ayant largement pénétré dans l'intérieur. Ces dunes recouvrent ou présentent en interstratification de très nombreux sites et monuments
préhistoriques, protohistoriques et antiques. A partir des résultats des études sédimentologiques et des datations, mise en évidence de 2 formations, chacune ayant subi bien des remaniements et ayant joué un temps son rôle de dune vivante : la dune ancienne et la
Origin and transformation of longitudinal sand dunes in the indian desert
Barkhane ; Dune ; Désert ; Eolien ; Géographie de l'Asie ; Géomorphodynamique ; Inde ; Rajasthan
champs de dunes soient rapportés génétiquement au système aérodynamique primaire de la région. Selon l'A., le modèle de Wilson (1971) pour le développement des dunes est le mieux adapté aux formes qu'il décrit. Les influences des variations du relief sur
L'A. a fait des observations géomorphologiques sur des associations de formes et la gradation spatiale de dunes longitudinales surtout dans le champ principal à l'ouest de Jaisalmer mais aussi en d'autres endroits du désert. Il suggère que ces
l'apparition des dunes longitudinales sont aussi discutées. En conclusion les dunes longitudinales du désert indien ne sont pas formées aux dépens des dunes paraboliques mais, à partir de la coalescence des barkhanes.
137 stratigraphic marker technique to evaluate recent sand movements in a dunesystem.
This paper will evaluate the depth distribution of Cs 137 in soils and near-shore dune sands of Pinery Provincial Park, Ontario, in order to relate soil properties to the Cs 137 distribution as well as to investigate the possibility of using the Cs