Spatial inventory of landforms in the recently exposed central highland of sub-Antarctic MarionIsland
Afrique du Sud ; Déglaciation ; Eolien ; Gelée ; Ile ; MarionIsland ; Prince Edward Island ; Périglaciaire ; Réchauffement climatique ; Zone froide
Aeolian features ; Climatic warming ; Cold area ; Deglaciation ; Frost ; Island ; Periglacial features ; Prince Edward Island ; South Africa
Until recently the central highland of sub-Antarctic MarionIsland was permanently covered with snow. Climatic amelioration has exposed the area, enabling the documentation of the geology and geomorphology. The lack of glacial and periglacial
Rock weathering characteristics as relative-age indicators for glacial and post-glacial landforms on MarionIsland
Afrique du Sud ; Datation relative ; Glaciaire ; Géochronologie ; MarionIsland ; Météorisation ; Postglaciaire ; Prince Edward Island ; Quaternaire ; Zone subantarctique
Geochronology ; Glacial features ; Postglacial ; Prince Edward Island ; Quaternary ; Relative dating ; South Africa ; Weathering
Rock weathering as relative-age indicators are tested on rock surfaces of generally known chronological sequence on Marionisland in the sub-Antarctic. While the weathering characteristics could not establish any chronosequence in the relict glacial
Sediment movement rates and processes on cinder cones in the maritime Subantarctic (MarionIsland)
Aiguille de glace ; Antarctique ; Australes terres ; Cône de cendres ; Dynamique de versant ; Gel ; Gel du sol ; MarionIsland ; Périglaciaire ; Reptation ; Versant ; Zone froide
This paper presents the results of a field experiment conducted on scoria cones on MarionIsland in the maritime Subantarctic. The paper, which describes the results of the most detailed and extensive geomorphological process study undertaken
The orientation of sorted stripes in the maritime subantarctic, MarionIsland
Dynamique de versant ; Glace ; Ile ; Océan Indien ; Pente de versant ; Prince Edward Island ; Périglaciaire ; Traînée avec triage ; Vent ; Zone froide ; Zone subantarctique
Cold area ; Ice ; Indian Ocean ; Island ; Periglacial features ; Prince Edward Island ; Slope dynamics ; Slope gradient ; Wind
The orientation of sorted stripes developed in glacial deposits on MarionIsland is examined. This study confirms earlier reports of preferential occurrence of sorted stripes on windward slopes. However, sorted stripes were also found to occur
The effect of synoptic scale weather systems on sub-surface soil temperatures in a diurnal frost environment : preliminary observations from sub-Antarctic MarionIsland
Antarctique ; Bilan radiatif ; Climatologie synoptique ; Désert ; Gel du sol ; MarionIsland ; Microclimat ; Radiation ; Région polaire ; Température du sol ; Zone froide
The aim of this paper is to attempt a first understanding of the synoptic weather conditions associated with soil frost occurrence on MarionIsland. Specifically, the AA. hypothesise that soil frost is dominant under specific air circulation
patterns and is associated with clear skies. The study was conducted in the interior of MarionIsland at Katedraalkrans in the polar desert habitat : scoria and black lava deposits almost completely unvegetated. Therefore this site allows for a direct
Déglaciation ; Faille ; Glaciation ; Géographie des régions polaires ; Isostasie ; MarionIsland ; Néotectonique ; Océan Indien ; Prince Edwards Islands ; Quaternaire zones froides ; Volcanisme
L'activité volcanique sur l'île Marion ne s'est produite que pendant les interglaciaires. La répartition des volcans est associée à un système de failles radiales et périphériques qui serait le résultat de la déglaciation, la localisation des
Fine scale variability in soil frost dynamics surrounding cushions of the dominant vascular plant species (Azorella selago) on sub-Antarctic MarionIsland
Antarctique ; Biogéographie ; Cycle gel-dégel ; Gel du sol ; MarionIsland ; Microclimat ; Microhabitat ; Propriétés du sol ; Végétation ; Zone froide
The AA. studied the fine scale variability in soil temperature and moisture parameters, specifically focusing on frost cycle characteristics around cushions of the dominant vascular plant species, Azorella selago, on sub-Antarctic MarionIsland
Afrique du Sud ; Antarctique ; Basalte ; Drakensberg ; Expérimentation ; Grès ; Humidité ; MarionIsland ; Météorisation ; Porosité ; Propriétés de la roche ; Sub-Antarctique
Rock samples from MarionIsland in the Sub-Antarctic and from the Drakensberg, South Africa were divided into sets and subjected to wetting and drying at 2 different moisture amplitudes to determine changes in physical rock properties. Rock porosity
En Islande, la géothermie supplée le manque d'énergie fossile. L'A. retrace l'histoire de l'utilisation de cette source d'énergie et présente la situation actuelle de l'Islande.―(D. Rouvière).
Plate boundary tectonics and oceanic island geomorphology in The geomorphology of plate boundaries and active continental margins.
This paper illustrates how studies of the geomorphology of oceanic islands can contribute to the understanding of nearby plate boundaries. For this purpose, an oceanic island is defined as one within an ocean basin. Case studies are given of three
contrasting situations : a) islands behind a subduction zone (the Law islands behind the Tonga trench in the Pacific| b) an island oceanwards of a trench (Christmas island near the Sunda trench in the Indian Ocean| c) islands scattered each side of a spreading