Results 161 to 170 of about 5,343,927 (201)

Inverse modelling of subglacial hydraulic processes

2023
Numerous studies have documented that water at the ice-bed interface can affect the ice flow dynamics of both mountain glaciers and ice sheets. Water at the bed is routed through a complex network of conduits that form a subglacial drainage system, which evolves over the melt season in response to the changes in the meltwater supply.
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Characteristics of the subglacially-formed debris-rich chemical deposits and related subglacial processes of Qiangyong Glacier, Tibet

Journal of Geographical Sciences, 2003
Subglacially-formed debris-rich chemical deposits were found both on bedrock surface and in bedrock crevice on the edge of Qiangyong Glacier, one of the continental glaciers in Tibet. Grain size distribution, internal structures and chemical components of the chemical deposits were analyzed.
Luo Risheng, Cao Jun, Liu Gengnian, Cui Zhijiu   +3 more
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Microstructural interpretations of modern and Pleistocene subglacially deformed sediments: the relative role of parent material and subglacial processes

Journal of Quaternary Science, 2001
AbstractAnalysis of till micromorphology represents a relatively new technique that has been used most frequently to infer the importance of subglacial shear in till genesis. This study aims to calibrate the technique by comparing Pleistocene tills from United Kingdom with a modern till (the UpB till) from beneath Ice Stream B, West Antarctica. Despite
Anjana Khatwa, Slawek Tulaczyk
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Assessing subglacial processes from diatom fragmentation patterns

Geology, 2004
Reconstructing the size and glacial style of past ice-sheet advances requires interpreting complex glacial sedimentary facies. We use diatoms, a major component of Antarctic continental shelf deposits, to infer the physical conditions under which these deposits were emplaced.
Reed P. Scherer, Charlotte M. Sjunneskog, Neal R. Iverson, Thomas S. Hooyer   +3 more
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Isotopic identification of subglacial processes

2010
A comprehensive stable isotope study of basal ice and debris layers in two Yukon surging glaciers suggests an isotopically variable basal freezing cycle. Trapridge and Backe Glaciers, St. Elias Range, Yukon, Canada, have parallel basal debris layers that extend for hundreds of metres along marginal ice faces and in meltwater tunnels.
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Processes and environmental significance of the subglacial chemical deposits in Tianshan Mountains

Science in China Series D: Earth Sciences, 2005
On the bedrock surface of Glacier No.1 in the headwater of Urumqi River, Tianshan Mts., well layered and crystallized subglacial calcite precipitations were discovered. Based on observations and analysis of the surface form, sedimentary texture and structure, and chemical composition of the deposits, clues about the subglacial processes and environment
Gengnian Liu, Risheng Luo, Jun Cao, Zhijiu Cui   +3 more
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An investigation of subglacial processes at the microscale from Briksdalsbreen, Norway

Sedimentology, 2006
AbstractThe subglacial processes at Briksdalsbreen, Norway, are examined by a combination of sedimentology, thin section and scanning electron microscope (SEM) analysis of till samples from an exposed subglacial surface and from beneath the glacier.
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Fabric Pattern in a Basal Till Succession and Its Significance for Reconstructing Subglacial Processes

Journal of Sedimentary Research, 2003
Abstract Fabric data from a 2.5-m-thick basal till succession in Kurzetnik, Poland, consisting of three structurally distinct till units including a deformation till were examined to test whether different processes of deposition and deformation as indicated by till structure are reflected in the till fabric pattern.
Larsen, N.K., Piotrowski, Jan A.
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Physical, chemical and biological processes in Lake Vostok and other Antarctic subglacial lakes

Nature, 2001
Over 70 lakes have now been identified beneath the Antarctic ice sheet. Although water from none of the lakes has been sampled directly, analysis of lake ice frozen (accreted) to the underside of the ice sheet above Lake Vostok, the largest of these lakes, has allowed inferences to be made on lake water chemistry and has revealed small quantities of ...
Siegert, MJ, Ellis-Evans, JC, Tranter, M, Mayer, C, Petit, J-R, Salamatin, A, Priscu, JC   +6 more
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Subglacial till: A physical framework for its properties and processes

Journal of Geophysical Research: Solid Earth, 1987
The continuum theory of mixtures provides a framework around which present knowledge of subglacial till can be organized. The proposed framework is provisional in two senses: the constitutive description of till will require improvement, and not all potentially significant processes have been included.
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