Varves in a proglaciallake, Sermilik, South East Greenland
Cold area ; Greenland ; Lacustrine sedimentation ; Lake ; Proglaciallake ; Sediment transport ; Varves
Three cores collected from a proglaciallake 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
Localised enhanced sedimentation from icebergs in a proglaciallake in Briksdal, Norway
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 proglaciallakes.
Late autumn runoff and sediment in a proglacial drainage system, Sermilik, east Greenland
Cold area ; Drainage ; Glaciology ; Greenland ; Hydrology ; Ice ; Proglaciallake ; Rill wash ; Sediment transport
The aim of this part of the investigation is to describe and quantify processes of sediment transport in late autumn and early winter. The relative importance of subglacial contribution is evaluated as well as the trap efficiency of a lake which
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
Proglaciallake-ice conveyors : a new mechanism for deposition of drift in polar environments
Aerial photography ; Antarctica ; Cold area ; Glacial features ; Glaciolacustrine ; Meltwater ; Moraine ; Polar region ; Proglaciallake ; Quaternary
This paper describes a new mechanism observed in a modern perennially ice-covered proglaciallake that documents the movement of glacial debris beyond the grounding line across the surface of the lake. This mechanism accounts for the absence
A continuous Holocene glacial record inferred from proglaciallake sediments in Banff National Park, Alberta, Canada
Alberta ; C 14 dating ; Canada ; Glacial features ; Glacier fluctuation ; Holocene ; Lacustrine sediment ; Proglaciallake ; Quaternary ; Rocky Mountains ; Tephrochronology
Sediment cores from 3 proglaciallakes in northern Banff National Park, Alberta, preserve a record of Holocene glacial activity upvalley which is more continuous and better dated than available surficial records. Dating of the cores is based
Changes in the bathymetry and volume of glacial Lake Agassiz between 9200 and 7700 C 14 yr B.P.
Bathymetry ; Holocene ; Lake ; Lake level ; Model ; North America ; Palaeogeography ; Palaeohydrology ; Proglaciallake
Computer reconstructions of the bathymetry of the lake were used to quantify variations in the size and form of Lake Agassiz during its final 2 phases (the Nipigon and Ojibway phases). The estimates of Lake Agassiz volumes and releases presented
here provide a quantitative basis for evaluating the impact that Lake Agassiz may have had on North America and on the oceans into which it flowed.
Proglacial sediment trapping in recently formed Silt Lake, Upper Lillooet Valley, Coast Mountains, British Columbia
British Columbia ; Canada ; Geochronology ; Glacier retreat ; Lacustrine sediment ; Lake ; Limnology ; Proglaciallake ; Sediment budget ; Turbidity ; Twentieth Century ; Varves
The sedimentology of proglacial Silt Lake was assessed by lake sediment coring and monitoring of lacustrine processes during a late-summer period of high glacier melt to characterize sediment delivery from the heavily glacierized catchment
and investigate the sediment trapping dynamics of this upland lake. A complete varve chronology was established for a distal basin of the lake which was exposed by Lillooet Glacier retreat between 1947 and 1962. The varve record showed decreasing sedimentation
rates in the basin while the glacier retreated, and as the lake became free of ice contact in the early 1970s. Although recession has continued over recent decades, and glacier proximity to the lake has, therefore, continued decreasing, lacustrine
The AA. review the different factors that potentially complicate inferences about climate-induced glacier response based on proglaciallake sediments. They discuss each component separately, starting with the climate forcing on the glacier mass
balance and resulting glacier volume and length variations; glacier sediment production and sediment fluxes out from glaciers and proglacial areas; and finally the glacio-lacustrine record of glacier variations. They exemplify the first two components
with data from Storglaciären, northern Sweden, and its proglacial river and surroundings. The AA. conclude that it is necesary to consider all possible influencing factors in order to derive reliable palaeoclimate data from lacustrine sediment sequences.
Erosion ; Glacial features ; Glacial valley ; Massachusetts ; Moraine ; Proglaciallake ; Rill wash ; United States ; Valley
that they were eroded by groundwater seeps fed by proglaciallakes dammed by the outwash plains and associated moraines. Valley erosion terminated after the lakes were drained and the water table dropped.
The AA. analyze the historical trends in channel pattern and the contemporary downstream changes in channel geometry, grain size, and gradient in the gravel bed, proglacial Sunwapta River, Alberta. The rational equations incorporate the effect
Early Pleistocene glacial Lake Lesley, West Branch Susquehanna River valley, central Pennsylvania
Dating ; Fluvioglacial features ; Geochronology ; Glacial features ; Palaeo-environment ; Palaeomagnetism ; Pennsylvania ; Pleistocene ; Proglaciallake ; Stratigraphy ; United States of America
of Glacial Lake Lesley. To achieve these objectives, detailed stratigraphic sections were described at McElhattan and Linden. The AA. use paleomagnetism as an age correlation tool in the WBSR valley to correlate contemporeanous glaciofluvial and proglacial
The AA. use new exposures in the West Branch Susquehanna River (WBSR) valley and magnetostratigraphy to reconstruct depositional environments in Glacial Lake Lesley, constrain the age of Glacial Lake Lesley, and constrain the maximum extent
The purpose of this paper is to assemble a comprehensive history of lake fluctuations in the Dry Valleys during the Late Quaternary, and to interpret these fluctuations, where possible, in terms of climatic and glacial changes.
Measurement, correlation, and mapping of glacial Lake Algonquin shorelines in northern Michigan
Cartography ; Correlation ; Global Positioning System ; Isostasy ; Lake ; Lake level ; Michigan ; Proglaciallake ; Quaternary ; Shoreline ; United States of America
The aim of this article is to produce accurate lake-level curves for Main Lake Algonquin and several post-Main lakes, evaluate/correlate the post-Main lakes in light of new data on shoreline elevations, and accurately map the areas inundated
by the various lake levels. The AA. use differential global positioning system (DGPS) technology to measure elevations of unquestionable Algonquin shorelines at wave-cut bluffs. They then correlate their shoreline data to previous estimates of post-Main Algonquin
features in an attempt to clarify the sequence of post-Algonquin lakes.
Seismic reflection study of recessional moraines beneath Lake Superior and their relationship to regional deglaciation
Amérique du Nord ; Déglaciation ; Glaciaire ; Great Lakes ; Géographie de l'Amérique ; Holocène ; Lake Superior ; Moraine de retrait ; Quaternaire zones moyennes ; Sismique réflexion
), and basal till (facies D). The prominent moraines of facies B are unusually thick and are believed to mark the ice-margin shorelines of successive major proglaciallakes that formerly occupied parts of western Lake Superior. The moraines are tentatively
An offlapping sequence of glacial and glacial-lacustrine sediments overlying bedrock is recognized in west-central Lake Superior that is progressively younger to the northeast. Four facies are recognized on the basis of geomorphologic and acoustic
properties and are interpreted to represent a southwest-to-northeast assemblage of: proglacial stratified drift (facies A), drift in major end moraines (facies B), till deposited as glacial retreat resumed, or possibly late-stage ablation till (facies C
correlated with Glacial Lake Duluth (unit 1), Glacial Lake Washburn (unit 2), and Glacial Lake Beaver Bay (unit 3), the most prominent of lakes drained via the progressively lower outlets via the Moose Lake/Brule-St. Croix Rivers, the Huron Mountains
is a blanket-like deposit containing deepwater ostracodes and occurs conformably within a thick (100 m) succession of deltaic and glaciolacustrine facies that record water depth changes in a large proglaciallake. The data indicate an ancestral early-mid
Glacial meltwater in Lake Huron during Early Postglacial Time as inferred from single-valve analysis of oxygen isotopes in ostracodes
Great Lakes ; Hydrochemistry ; Isotope analysis ; Lake ; Lake level ; Meltwater ; Oxygen 18 ; Palaeogeography ; Proglaciallake ; Quaternary ; United States of America
Analyse isotopique ; Eau de fonte ; Etats-Unis ; Great Lakes ; Hydrochimie ; Lac ; Lac proglaciaire ; Niveau lacustre ; Oxygène 18 ; Paléogéographie ; Quaternaire
δ18O measurements of benthic ostracodes are used to reconstruct the δ18O history of Lake Huron and Georgian Bay water between 10,600 and 7600 14C yr B.P. This δ18O record was calibrated using a comparison of the δ18O values of modern ostracodes
The aims of this paper are to : identify thaw lakes and drained thaw lake basins (DTLBs) in the western Arctic Coastal Plain (ACP); develop several geometric shape metrics for lakes and basins, and perform statistically-based spatial
and morphometric analyses to compare lakes and basin metrics within and between 3 subregions of the ACP. The primary purposes are to determine if significant differences in shape metrics exist across space, to determine if such metrics can be used to discriminate