inscription
Portail d'information géographique

Résultats de la recherche (1321 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Sedimentological and geomorphological impacts of the jökulhlaup (glacial outburst flood) in january 2002 at Kverkfjöll, northern Iceland
  • Geomorphology ; Glacial features ; Glacial surge ; Iceland ; Impact ; Natural hazards ; Risk management ; Sedimentology
  • Crue glaciaire ; Date 2002 ; Gestion du risque ; Glaciaire ; Géomorphologie ; Impact ; Islande ; Risque naturel ; Sédimentologie
  • This study provides a clearer understanding of hydrological and sedimentological processes and mechanisms operating during jökulhlaups (glacial outburst floods), and helps to identify flood hazards more accurately, which is fundamental for hazard
  • management and minimizing risk.
  • Jökulhlaups circa Landnám : mid- to late first millennium AD floods in South Iceland and their implications for landscapes of settlement
  • C 14 dating ; Glacial surge ; Holocene ; Human occupation ; Iceland ; Quaternary ; Sandur ; Sedimentology ; Tephrochronology
  • This paper presents geomorphological and sedimentological evidence for 3 large-scale floods to the west of the ice-capped volcano Katla around the time of Norse settlement or Landnám (AD 870-930). These glacial outburst floods (jökulhlaups
  • ), the most recent prehistoric events in a series of Holocene floods in the Markarfljót valley, are securely dated by tephrochronology and radiocarbon dating to between c. AD 500 and c. AD 900. The environmental impact of these events would have been extensive
  • , affecting both the highlands and the coastal lowlands where about 15 of the 400 or so landnám farms in Iceland were sited.
  • Physical-scale modelling of jökulhlaups (glacial outburst floods) with contrasting hydrograph shapes
  • Geomorphology ; Glacial features ; Glacial surge ; Impact ; Model ; Sedimentology
  • Crue glaciaire ; Glaciaire ; Géomorphologie ; Impact ; Modèle ; Sédimentologie
  • hydrograph shapes produced different sedimentary and geomorphic impacts. For this purpose, an exponentially rising and a linearly rising jökulhlaup were modelled.
  • Basal processes beneath an Arctic glacier and their geomorphic imprint after a surge, Elisebreen, Svalbard
  • Arctic Region ; Cold area ; Glacial surge ; Glacier ; Glacier dynamics ; Moraine ; Polar region ; Sedimentology ; Svalbard
  • criteria derived from observations of surging glaciers elsewhere and find that ice-flow instability can be inferred when geomorphological criteria are combined with sedimentological data.
  • The aim of this study is to identify ice-flow instability, e.g., surge-related events, for a retreating glacier with unknown surge record. The AA. compare the landform assemblage from the foreground of Elisebreen with hypothesized geomorphological
  • Relationships between flow hydraulics, sediment supply, bedload transport and channel stability in the proglacial Virkisa River, Iceland
  • Braided channel ; Carrying capacity ; Channel geometry ; Cold area ; Glacial surge ; Iceland ; Sediment transport ; Stream
  • The AA. present data from a proglacial river in Iceland that exhibits very different sedimentological characteristics when compared to its alpine counterparts. On the basis of their observations the AA. conclude that braidplain morphology
  • is controlled by low frequency, high magnitude flow events, possibly associated with glacial outburst floods. This is in marked contrast to process-form relationships in more dynamic alpine proglacial channels that are characterised by high rates of sediment
  • Cold area ; Floating ice processes ; Geomorphology ; Glacial features ; Grain size distribution;Granulometry ; Ice ; Iceland ; Moraine ; Pebbles ; Sandur ; Sedimentology ; Stratigraphy
  • This paper investigates the origin of a series of ring structures developed on Myrdalssandur, south Iceland, following a major, volcanilly-trigerred jökulhaup in 1918.
  • A polygenetic landform at Stígá, Öraefajοkull, southern Iceland
  • Glacial features ; Glacier fluctuation ; Iceland ; Lithology ; Moraine ; Palaeo-environment ; Palaeogeomorphology ; Periglacial features ; Sedimentology
  • This paper describes and accounts for the formation of a ridge of unconsolidated sediment located adjacent to the foot of a talus slope in a recently glaciated valley, in southern Iceland. Specific processes associated with the development
  • of this landform are identified through morphological, sedimentological and lithological analyses. Implications for the interpretation of palaeo-landforms are demonstrated.
  • Antarctica ; Climatic warming ; Geomorphology ; Glacial features ; Glacial surge ; Glaciation ; Glacier ; Glacier fluctuation ; Glaciology ; Global change ; Ice sheet ; Palaeo-environment ; Quaternary ; Sea level ; Sedimentology
  • Braided channel ; Canada ; Channel geometry ; Flood ; Geomorphogenesis ; Glacial erosion ; Glacial surge ; Meltwater ; Model ; Ontario ; River bed ; Sedimentology ; Valley
  • on the major theories which attempt to explain their formation. Before doing so, however, it summarizes salient aspects of tunnel valley geomorphology, and the sedimentology of their infills. Tunnel valleys incised into both bedrock and unconsolidated sediments
  • Debris entrainment by basal freeze-on and thrusting during the 1995-1998 surge of Kuannersuit Glacier on Disko Island, west Greenland
  • Deuterium ; Freezing ; Geophysics ; Glacial features ; Glacial surge ; Glacial valley ; Glacier dynamics ; Greenland ; Ground ice ; Isotope analysis ; Oxygen 18 ; Sediment transport
  • Kuannersuit Glacier, a valley glacier on Disko Island, experienced a major surge from 1995 to 1998. The aim of this study is to describe the tectonic evolution of large englacial thrusts and the processes of basal ice formation using a multiproxy
  • approach including structural glaciology, stable isotope composition (δ18O and δD), sedimentology and ground-penetrating radar. The AA. argue that the major debris layers that can be traced in the terminal zone represent englacial thrusts that were formed
  • early during the surge. They interpret the stratified basal ice as a continuum formed mainly by freeze-on processes and localized regelation. The dispersed basal ice facies (D) was mainly formed by secondary processes where fine-grained sediment
  • during a glacier surge.
  • Arctic Region ; Cold area ; Geochronology ; Glacial features ; Glacial surge ; Glacier ; Glacier fluctuation ; Lichenometry ; Moraine ; Sedimentology ; Spitsbergen ; Svalbard
  • In this paper, 2 push moraine systems associated with 2 small subpolar glaciers, Finsterwalderbreen and Penckbreen, were investigated. This study showed that at these glaciers the push moraines were formed in association with surges, which producted
  • a different style of moraine depending on the rheology of the deformed material and the glacial history. The moraines are similar in that they are formed by folded outwash sediments and contain little till. However, the forms of these moraines are very
  • Coastal dynamics and impact of coastal protection works on the Spurn Head spit (UK)
  • Coastal dynamics ; Coastal environment ; Coastal protection ; England ; Estuary ; Geomorphology ; Human impact ; Impact ; Sedimentology ; Spit ; Tide ; United Kingdom ; Wave ; Weather type
  • Action anthropique ; Dynamique littorale ; England ; Estuaire ; Flèche littorale ; Géomorphologie ; Impact ; Littoral ; Marée ; Protection du littoral ; Royaume-Uni ; Sédimentologie ; Type de temps ; Vague
  • the sedimentology and geomorphology of the spit and of the tidal flat behind it (Spurn Bight), and assesses the effects of coastal defences on the nearshore dynamics. The geomorphology and sedimentology of the beaches and the tidal flat were studied to assess
  • The erosion of the glacial tills along the Holderness Coast (eastern England) has released material which has led to the formation of a 4.5 km sand and gravel spit, Spurn Head, across the mouth of the Humber estuary. This paper examines
  • Glacial geomorphology of Bonney drift, Taylor valley, Antarctica
  • Glacial and paleoclimatic history of the Ross ice drainage system of Antarctica. Special issue
  • Aerial photography ; Antarctica ; Cold area ; Geomorphology ; Glacial features ; Grain size distribution ; Mass movement ; Moraine ; Quaternary ; Sedimentology
  • Lake-ice conveyor deposits : geomorphology, sedimentology, and importance in reconstructing the glacial history of the Dry Valleys
  • 34th Binghamton geomorphology symposium. Ice sheet geomorphology - past and present processes and landform
  • Antarctica ; Geomorphology ; Glacier ; History ; Lake ; Proglacial lake ; Sedimentation
  • Comparative study ; Glacial features ; Glacier ; Glacier margin ; Iceland ; Lithology ; Micromorphology ; Moraine ; Palaeo-environment ; Scotland ; Sedimentology ; United Kingdom
  • Macro- and micro-scale sedimentological analyses of recently deposited tills and complex push/squeeze moraines on the forelands of Icelandic glaciers and in a stacked till sequence at the former Younger Dryas margin of the Loch Lomond glacier lobe
  • in Scotland are used to assess the depositional processes involved in glacier submarginal emplacement of sediment. The AA. employed clast fabric analyses, micro-morphology, sedimentological logging and structural logging in order to combine micro-scale
  • Sedimentology, stratigraphy, and geomorphology of glacial lake Calgary at Cochrane, Alberta, Canada
  • Alberta ; Canada ; Deglaciation ; Glacial lake ; Glaciolacustrine ; Palaeo-environment ; Quaternary ; Sedimentology ; Stratigraphy
  • Glacial deposit ; Glacial features ; Glacial valley ; Glacier ; Karokoram ; Pakistan ; Periglacial geomorphology ; Sedimentology ; Spatial distribution
  • A late-glacial/Holocene pollen record from the Eastern Andes of Northern Peru
  • Andes ; C 14 dating ; Climatic variation ; Holocene ; Human impact ; Lacustrine sedimentation ; Lateglacial ; Palaeo-ecology ; Palynology ; Peru ; Pollen diagram ; Quaternary
  • The objectives of this study are to look for evidence of late-glacial and Holocene climatic fluctuations in the fossil pollen and sedimentological record from Laguna Baja, and to examine the fossil pollen record for evidence of human impact
  • Till - as a glacial tectomict, its internal architecture, and the development of a typing method for till differentiation
  • 34th Binghamton geomorphology symposium. Ice sheet geomorphology - past and present processes and landform
  • Canada ; Classification ; Geomorphology ; Micromorphology ; Moraine ; Ontario ; Sedimentology
  • Glacigenic properties of till. Studies in glacial sedimentology from the Allgäu Alps and The Netherlands.
  • The intention of this study is to give a contribution to the knowledge of sedimentological properties of glacial diamictons, in particular those of subglacial origin. (AIS).