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The Continental Sedimentary Environment
Published in Aurèle Parriaux, Geology, 2018
Deposits formed directly from the movement of ice are called moraines. The shape and composition of moraines vary widely according to their processes of formation and the rocky material associated with them.
The Continental Sedimentary Environment
Published in Aurèle Parriaux, Geology, 2018
Deposits formed directly from the movement of ice are called moraines. The shape and composition of moraines vary widely according to their processes of formation and the rocky material associated with them.
Groundwater Targeting Using Remote Sensing
Published in Prasad S. Thenkabail, Remote Sensing Handbook, 2015
The retreat and advancement of glaciers due to climatic changes have given rise to a complex and often uncertain distribution of beds of sand and gravel. The coarse fractions are generally found close to the ice front or along channels of large streams. Rock debris chiefly of glacial origin is called glacial “drift.” Drift includes “till,” a highly heterogeneous and mostly nonstratified material consisting of bolder clay deposited directly from ice. The thickness of glacial deposit varies between several meters and several tens of meters, but rarely exceeds 100 m. They often form elongated ridges called moraines.
Runoff generation from a combined glacier and páramo catchment within the Antisana Reserve in Ecuador
Published in Journal of Ecohydraulics, 2021
Veronica Minaya, Vivian Camacho Suarez, Jochen Wenninger, Arthur Mynett
The geology as shown in Figure 1d is composed of the glacier, moraines, glacial-fluvial sediments, tillites, volcanic rocks and Lahar rojo. The moraines are deposited debris that form along the glacier due to the receding of the glacier. These areas are characterized by lagune formations which intercept meltwater. The Lavas Pleistocene formation is older volcanic pyroclastic deposits which are composed of andesite rocks containing plagioclase, amphibole and feldspar minerals (Hall et al. 2012). The Hialina Lava is formed also of andesite content; however, this is a younger formation with olivine, plagioclase and quartz, arranged in a matrix formed by volcanic glass (Alvarado 2009). The Lahar Rojo is a sequence of red volcanic lava deposits along the Antisana river. Its pyroclastic material when mixed with water became red indicating several volcanic eruptions during the Holocene.
Review of moraine dam failure mechanism
Published in Geomatics, Natural Hazards and Risk, 2019
Robin Neupane, Huayong Chen, Chunran Cao
Most of the moraine dams are made up of poorly consolidated and sorted sediments, and have a relatively low width-to-height ratio than those of landslide dams (Evans and Clague 1994), making them vulnerable to failure. Therefore, the research of mitigation techniques such as hydraulic syphon techniques for lowering the lake level (Grabs and Hanisch 1992) and hazard assessments of the areas downstream (Somos-Valenzuela et al. 2016) is entailed. Hydraulic studies related to dam safety is required for hazard assessments in moraine dam failure prone areas (Pilotti et al. 2014). However, the study of the mechanism of moraine dam failure is equally important for the full understanding of these events that will help in the careful planning of prevention works.
Multitechnique approach for characterizing the hydrogeology of aquifer systems: application to the Mauricie region of Québec, Canada
Published in Canadian Water Resources Journal / Revue canadienne des ressources hydriques, 2023
Yan Lévesque, Julien Walter, Lamine Boumaiza, Mélanie Lambert, Anouck Ferroud, Romain Chesnaux
According to Occhietti (2007, 2011), the stratigraphic sections of the moraine comprise a variety of sedimentary facies, including till wedges, subglacial till from the last glaciation, proximal and distal glaciomarine deposits, as well as glaciofluvial and ice-marginal outwash deposits. In low-lying areas around the moraine, the Champlain Sea deposited a thick layer of clay covered by regressive sand during its retreat. Consequently, this imposing glacial sediment complex is partially confined on its sides by clay, thus retaining water inside the moraine. At higher elevations, such as along the sides and on top of the moraine, the Champlain Sea left behind proximal glaciomarine sediments and reworked the glacial tills deposited during the Younger Dryas readvance (Daigneault and Occhietti 2007; Occhietti 2007; Parent and Occhietti 2007, 1999). As a result of wave and current reworking, visible terraces formed on the seaward side of the moraine, mainly composed of coastal and sublittoral sand deposited in the shallow areas of the Champlain Sea and glaciofluvial sediments from small and large deltas in the valleys at the mouths of rivers flowing into the Champlain Sea (Parent and Occhietti 2007; Occhietti 2007; Occhietti et al. 2002). Locally, numerous well-sorted sand and gravel areas have been observed in the moraine; these deposits constitute potential aquifers (Lévesque, Walter, and Chesnaux 2021). When exposed at the surface, these permeable units can also serve as recharge areas for the moraine and the underlying rocky aquifers. The importance of the local aquifer capacity is evidenced by the surrounding municipalities (e.g. St-Narcisse, St-Prosper-de-Champlain, St-Maurice, Ste-Geneviève-de-Batiscan) that exploit the moraine locally to supply drinking water.