Localised enhanced sedimentation from icebergs in a proglacial lake in Briksdal, Norway
Glaciaire ; Géographie physique ; Iceberg ; Lac proglaciaire ; Norvège ; Sédimentologie ; Transport sédimentaire ; Zone froide
Studies of the ice-contact proglacial Briksdal Lake have demonstrated that drifting icebergs congregate in a well-defined zone near the outlet. Deposition of the englacial debris from decaying icebergs is concentrated within this area forming
a shallow underwater shelf and associated beach. It is suggested that this process may have characterized former proglacial lakes.
Varves in a proglacial lake, Sermilik, South East Greenland
Groenland ; Lac ; Lac proglaciaire ; Sédimentation lacustre ; Transport sédimentaire ; Varve ; Zone froide
Cold area ; Greenland ; Lacustrine sedimentation ; Lake ; Proglacial lake ; Sediment transport ; Varves
Three cores collected from a proglacial lake with an Axelsson corer are x-rayed. The stratification is interpreted as varves. The cores cover periods of sedimentation with a duration from 5-23 years. The average thickness of the varves vary from 1.9
Sediment transport in a proglacial valley, Sermilik, East Greenland
Glaciaire ; Groenland ; Hydrologie ; Modèle ; Transport sédimentaire ; Vallée ; Variation climatique ; Zone froide
Detailed investigations of sediment transport have been carried out in a proglacial valley at the Mitdluagkat Glacier in East Greenland. The results from 1989, 1990 and 1991 have been compared with earlier measurements of sediment transport
This paper describes the morphology and infers the process of formation, of a proglacial icing in Svalbard. The study glacier, Scott Turnerbreen, with an altitude range of 230-680 m a.s.l., is located in central Spitsbergen.
Late autumn runoff and sediment in a proglacial drainage system, Sermilik, east Greenland
Drainage ; Glace ; Glaciologie ; Groenland ; Hydrologie ; Lac proglaciaire ; Ruissellement ; Transport sédimentaire ; Zone froide
Cold area ; Drainage ; Glaciology ; Greenland ; Hydrology ; Ice ; Proglacial lake ; Rill wash ; Sediment transport
receives water from the northern flanks of the Mitdluagkat glacier. It was clearly demonstrated that the formation of frazil ice and anchor ice caused increased sediment transport, dominating the total load of the proglacial stream during the measuring
Energetics of alpine proglacial geomorphic processes
Cold area ; Energy balance ; Glacial features ; Mass movement ; Mountain ; Proglacialzone ; Sediment budget ; Switzerland ; Valais
Bilan sédimentaire ; Bilan énergétique ; Glaciaire ; Montagne ; Mouvement de masse ; Suisse ; Valais ; Zone froide ; Zone proglaciaire
This paper discusses the merits of an energetics approach to quantifying sediment transfer processes in the Bas Glacier d'Arolla proglacialzone, Valais, during the 1987 melt-season. Energy estimates, based on sediment transfer processes, range over
eight orders of magnitude. Both estimates of mass transfer and work emphasize the overwhelming importance of the meltwater channel and valley train within the proglacial sediment system. Based on energy and power magnitudes three sediment budget process
Relationships between flow hydraulics, sediment supply, bedload transport and channel stability in the proglacial Virkisa River, Iceland
Capacité de charge ; Chenal anastomosé ; Cours d'eau ; Crue glaciaire ; Géométrie hydraulique ; Islande ; Transport sédimentaire ; Zone froide
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
Proglacial lake-ice conveyors : a new mechanism for deposition of drift in polar environments
Antarctique ; Eau de fonte ; Glaciaire ; Glaciolacustre ; Lac proglaciaire ; Moraine ; Photographie aérienne ; Quaternaire ; Région polaire ; Transport glaciaire ; Zone froide
Aerial photography ; Antarctica ; Cold area ; Glacial features ; Glaciolacustrine ; Meltwater ; Moraine ; Polar region ; Proglacial lake ; Quaternary
This paper describes a new mechanism observed in a modern perennially ice-covered proglacial lake that documents the movement of glacial debris beyond the grounding line across the surface of the lake. This mechanism accounts for the absence
Channel pattern of proglacial rivers : topographic forcing due to glacier retreat
Chenal anastomosé ; Cours d'eau ; Déglaciation ; Géométrie hydraulique ; Islande ; Lit fluvial ; Paléohydrologie ; Proglaciaire ; Recul du glacier ; Topographie ; Zone froide
Braided channel ; Channel geometry ; Cold area ; Deglaciation ; Glacier retreat ; Iceland ; Palaeohydrology ; Proglacial features ; River bed ; Stream ; Topography
This paper compares widely used models of river channel pattern against the changes observed at Skaftafellsjökull, Iceland. Topography was found to play a large role in determining channel pattern in proglacial environments for 2 reasons : 1
) glacier retreat forces rivers to flow through confined moraine reaches; 2) proximal incision of proglacial rivers, accompanied by downstream aggradation, leads to changes in slope which force the river to cross channel pattern thresholds. The findings
of this work indicate that in the short term, the majority of channel pattern change in proglacial rivers is due to topographic forcing, and that changes due to changing hydrology and sediment supply are initially relatively minor, although likely to increase
Application of a 3D laser scanner in the assessment of erosion and deposition volumes and channel change in a proglacial river
This study reports the use of a high-resolution 3D laser scanner in the assessment of erosion and deposition volumes in the proglacialzone of Glacier du Ferpècle and Mont Miné, Switzerland. High-resolution data obtained across a braid plain during
Advance of part of the margin of the Greenland ice sheet across a proglacial moraine ridge between 1968 and 2002 caused progressive changes in moraine morphology, basal ice formation, debris release, ice-marginal sediment storage, and sediment
Alpes ; Années 1850-2000 ; Chronoséquence ; Déglaciation ; Géochimie ; Matière organique ; Propriétés du sol ; Sol ; Suisse ; Zone proglaciaire
The AA. study the formation of soil organic matter and its different fractions within a time span of 0–150 years. They investigated a chronosequence of very young soils in the proglacial area Morteratsch (Swiss Alps) to derive time-trends of soil
. Observations made along the glacier front suggest that the formation of these moraines can best be described as bulldozed moraines. Large boulders left in the proglacial areas are pushed forward, forming pressure ridges on the distal side. Some of the largest
Glacial landform sediment associations are reported and the implications for glacigenic depositional sequences are discussed for areas that have experienced proglacial thrusting.
Analyse de régression ; Arctique ; Charge en suspension ; Eau de fonte ; Fluvioglaciaire ; Glacier ; Modèle ; Svalbard ; Zone froide
This paper presents a quantitative comparison of proglacial suspended sediment transport dynamics in three contrasting arctic glacier basins : one largely cold-based glacier (Austre Brøggerbreen), one largely warm-based glacier (Finsterwalderbreen
) and one intermediate polythermal glacier (Erdmannbreen). Temporal dynamics of the different suspended sediment transport systems will be inferred from the structure of statistical models which best explain the variance of proglacial suspended sediment
Analyse de régression ; Analyse quantitative ; Arctique ; Charge en suspension ; Fluvioglaciaire ; Glacier ; Modèle ; Svalbard ; Transport sédimentaire ; Zone froide
This paper presents a quantitative comparison of proglacial suspended sediment transport dynamics in 3 contrasting arctic glacier basins. The study sites include a largely cold-based glacier, a largely warm-based glacier and an intermediate type
of polythermal-based glacier. Temporal dynamics of the different suspended sediment transport systems will be inferred from the structure of statistical models which best explain the variance of proglacial suspended sediment concentration (SSC). This constitutes
British Columbia ; Canada ; Charge en suspension ; Cours d'eau ; Instrumentation ; Mesure de terrain ; Technique de recherche ; Turbidité ; Zone froide
This paper details the design and performance of such a turbidimeter (the HOBS Harry's Optical Backscatter Sensor) developed for spatially distributed monitoring of suspended sediment in proglacial streams. The effectiveness of the HOBS
in determining suspended sediment concentration is determined using bulk field sediment in the laboratory, and its field performance assessed from a network installed for one ablation season in 2 proglacial streams at Small River Glacier in the Canadian Rockies.