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Air and Climate
Published in Cameron La Follette , Chris Maser, Sustainability and the Rights of Nature, 2017
Cameron La Follette , Chris Maser
On the other hand, most of the dust in Antarctic ice cores originates from the glacial outwash in Patagonia. (Glacial outwash refers to the sediments deposited by streams that are flowing away from glaciers.) Sedimentary evidence suggests that proglacial lakes provided an on/off switch for the flux of dust to Antarctica during the last glacial period. Peaks in the amount of dust coincide with periods when the rivers of glacial meltwater (water that comes directly from melting snow or ice) deposited sediment directly onto easily mobilized outwash plains, but no such peaks occurred when glacial meltwater went directly into proglacial lakes. (A proglacial lake is a lake formed either by the damming action of a moraine or ice during the retreat of a melting glacier. A moraine, in turn, is an accumulation of loose soil and rock carried by an advancing glacier and left at its front and side edges as it retreats.)21
Water retention in a steep moraine slope during periods of heavy rain
Published in H. Rahardjo, D.G. Toll, E.C. Leong, Unsaturated Soils for Asia, 2020
Ph. Teysseire, L. Cortona, S.M. Springman
Outbursts of proglacial lakes, caused by recession of glaciers and retained behind moraine dams, constitute a major natural hazard and often produce extreme discharge. Five major glacier floods/ debris flow were documented during 19th and 20th century, the latest one in 1970, for the village of Saas-Balen, Saas Valley, Valais/Switzerland (Haeberli, 1992)
Sedimentary Environments and Facies
Published in Supriya Sengupta, Introduction to Sedimentology, 2017
Proglacial lakes, which are in direct contact with the ice sheets, are fed by meltwater conduits, subaqueous fans and by ice rafting. The accumulation of suspended sediments and stratified rafted debris (diamictites in these lakes) are overlain by cross-bedded, deltaic silty sand. Dropstones are common.
Results from the Quebec Groundwater Knowledge Acquisition Program
Published in Canadian Water Resources Journal / Revue canadienne des ressources hydriques, 2018
Marie Larocque, Vincent Cloutier, Jana Levison, Eric Rosa
The studied PACES regions are distributed over a large area of the meridional portion of the Province of Quebec (Figure 1). The territory has highly diversified geology and contrasting climate conditions, thus influencing the hydrogeology of the studied regions. The projects cover three hydrogeolocal regions of Canada described by Rivera (2014): (1) the Precambrian Shield, (2) the St. Lawrence Lowlands, and (3) the Appalachians. These hydrogeological regions correspond to important geological domains of Québec, i.e. the Superior and Grenville provinces, the St. Lawrence Platform, and the Appalachian Province. The last glaciation/deglaciation cycle, with the deposition of unconsolidated sediments, the formation of proglacial lakes and marine invasions, had major impacts on the shaping of the landscape, as well as on the hydrogeology and hydrogeochemistry of the aquifer systems. Details of these geological contexts are presented in the 10 articles. The papers focus on three main components of aquifer characterization, i.e. aquifer geometry (Légaré-Couture et al. 2018; Nadeau et al. 2018; Walter et al. 2018), hydrogeochemistry and isotope tracers (Chaillou et al. 2018; Rey et al. 2018; Beaudry et al. 2018), and groundwater flow modeling and particle tracking (Gagné et al. 2018; Janos et al. 2018; Montcoudiol et al. 2018; Turgeon et al. 2018). The paper by Walter et al. (2018) combines the topics of geometry and hydrogeochemistry.
Glacial lake changes and outburst flood hazard in Chandra basin, North-Western Indian Himalaya
Published in Geomatics, Natural Hazards and Risk, 2018
The analysis of temporal glacial lake inventory reveals that rate of formation of supraglacial lake and rate of expansion of proglacial lake have increased significantly from 2002 to 2014. The analysis and inferences about formation and expansion of glacial lakes are concomitant with other studies in the Himalayan region (Zhang et al. 2015; Govindha Raj and Kumar 2016; Song et al. 2016; Nie et al. 2017). Rapid expansion of proglacial moraine-dammed lakes is a well observed phenomenon throughout the Hindu-Kush-Himalayan region contributing most of the increased glacial lake area (Wang et al. 2011; Zhang et al. 2015; Govindha Raj and Kumar 2016; Song et al. 2016). Most of the bedrock-dammed lakes are stable growing at lesser rate as compared to moraine-dammed lakes and Ice-dammed lakes. Moraine-dammed existed as perennial lakes with rapid expansion rate. The ice-dammed lakes or supra-glacier lakes/ponds are highly variable in terms of formation, spatial location, size and growth rate in the study area. The characteristics exhibited by the different types of glacial lakes in Chandra basin are consistent with the various other studies in Himalayan region (Benn et al. 2001; Wang et al. 2016; Nie et al. 2017).
LiDAR-based mapping of paleo-ice streams in the eastern Great Lakes sector of the Laurentide Ice Sheet and a model for the evolution of drumlins and MSGLs
Published in GFF, 2018
Shane Sookhan, Nick Eyles, Niko Putkinen
The bedrock basins of lakes Erie and Ontario are separated by the Niagara Peninsula of Southern Ontario but together comprise a 600 km long depression through which water drains eastwards into the St. Lawrence River and the Atlantic. During successive glaciations it acts as a major conduit for ice entering and leaving the Great Lakes region from the southern Quebec centre of the Laurentide Ice Sheet (LIS; Occhietti et al. 2001, 2011) (Figs. 1 and 2). The Erie-Ontario drainage basin as a whole, includes a large part of Southern Ontario in Canada, and extends into the USA south to the Finger Lakes, west into Pennsylvania and Ohio and east to the Catskill and Adirondack mountains of New York State to the Hudson River Valley (Fig. 2). Much of this area is underlain by soft, easily eroded Paleozoic shales and glacial sediments such as tills and glaciolacustrine deposits recording interruption of eastwards Great Lake drainage and extensive ponding of deep proglacial lakes both during ice advance and retreat. The area has long attracted the attention of glacial geologists because it contains an impressive geomorphic record of former ice flow dynamics represented by more than 15,000 drumlins (Fairchild 1900, 1907, 1911, 1929, 1932; Hubbard 1906; Slater 1929; Putnam & Chapman 1943; Gravenor 1953, 1957; Miller 1971, 1974; Potter & Potter 1971; Muller 1974; Crozier 1975; White 1985; Francek 1991; Boyce & Eyles 1991; Menzies et al. 1997, 2016; Hart 1999; Briner 2007; Kerr & Eyles 2007; Hess & Briner, 2009; Gentoso et al. 2012; Maclachlan & Eyles 2013; Eyles & Doughty 2016; Sookhan et al. 2018). As a consequence of newly available, high resolution digital imagery for this area, numerous corridors of subglacial landforms previously reported as “flute-like” (Fairchild 1929; Hart 1999; Hess & Briner 2009) can now be more properly identified as flow sets of “megascale glacial lineations” (MSGLs) recording the former presence of fast flowing paleo-ice streams (Hess & Briner 2009; Eyles & Doughty 2016; Sookhan et al. 2018).