Article
Geography, Physical
Richard B. Alley, Nick Holschuh, Byron Parizek, Lucas K. Zoet, Kiya Riverman, Atsuhiro Muto, Knut Christianson, Elisabeth Clyne, Sridhar Anandakrishnan, Nathan T. Stevens
Summary: Poorly known glacier-bed characteristics have significant impacts on projected sea-level rise from ice-sheet changes, particularly in the Thwaites Glacier drainage of West Antarctica. Different types of glacier beds can affect ice flow velocity and thinning, playing a crucial role in predicting future forced sea-level rise.
ANNALS OF GLACIOLOGY
(2022)
Article
Geology
Izabella Remmert, Mark D. Johnson, Olof Johansson Strom, Mark Peternell, Gustaf Peterson Becher
Summary: Current melting of glaciers has increased interest in understanding glacier hydrology and the interplay between subglacial meltwater, the glacier bed, and ice behavior. However, little is known about the sedimentology of subglacial meltwater deposits, and no sediment type or sequence has been identified as being unique to subglacial settings.
SEDIMENTARY GEOLOGY
(2022)
Article
Geography, Physical
Joni Makinen, Kari Kajuutti, Antti E. K. Ojala, Elina Ahokangas, Aleksi Tuunainen, Markus Valkama, Jukka-Pekka Palmu
Summary: The purpose of this paper is to describe the structure and composition of subglacial landforms called murtoos in order to understand their formation and depositional environment. Murtoos have been found in Finland and Sweden and are likely to exist in all areas covered by past ice sheets. They occur in fields along subglacial meltwater routes and are composed of sandy and gravelly sediments interbedded with sorted sediments. Murtoos were formed by sediment-concentrated flows during weak glaciotectonic deformation, indicating near-zero pressure.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
Keith Makinson, Daniel Ashurst, Paul G. D. Anker, James A. Smith, Dominic A. Hodgson, Peter E. D. Davis, Andrew M. Smith
Summary: Subglacial sediments can provide insights into glacier flow, ice-sheet history, and life in those environments. To address the challenges of retrieving sediments from beneath the ice, British Antarctic Survey and UWITEC developed a new auto-release-recovery percussion hammer mechanism, which makes coring operations depth-independent and improves efficiency.
ANNALS OF GLACIOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Dao-Tao Dong, Long-Wei Qiu, Peng-Jie Ma, Guo-Ding Yu, Yu-Zhe Wang, Shi-Bo Zhou, Bao-Liang Yang, He-Qing Huang, Yong-Qiang Yang, Xin Li
Summary: Investigating the formation and evolution of coarse-grained deposits in modern lakes is crucial for predicting reservoir sandbodies, disaster prediction, and limnological research. The source-to-sink system of coarse-grained deposits in Lake Chenghai shows that the formation and evolution are controlled by sediment flux and the geomorphic evolution of the source areas and sink regimes. The morphology and distribution of coarse-grained deposits vary depending on differences in quantity and composition of materials from different source areas.
JOURNAL OF PALAEOGEOGRAPHY-ENGLISH
(2022)
Review
Geology
Beata Gruszka, Tomasz Zielinski
Summary: Although deltas and subaqueous fans are formed in near-shore zones of basins, their hydraulic conditions, depositional mechanisms, and lithofacies characteristics differ. Subaqueous fans, which are relatively poorly understood and often overlooked in lacustrine sedimentological interpretations, exhibit significant paleoenvironmental and lithological differences compared to deltas.
Article
Geology
Zaki A. Abdel-Fattah, Haytham Sehsah
Summary: The paper presents new data and results that improve the depositional models of lacustrine and alluvial fan deposits in the Precambrian. Siliciclastic profiles in the Kareim Basin provide evidence of Late Neoproterozoic lacustrine/fan delta and alluvial fan settings. Thirteen depositional facies belonging to six facies associations are defined based on detailed sedimentologic data. The incorporation of facies architectures, sedimentary structures, stratigraphic relations, and depositional patterns suggests three inter-related depositional phases.
SEDIMENTARY GEOLOGY
(2023)
Article
Multidisciplinary Sciences
Matteo Fabbri, Guillermo Navalon, Roger B. J. Benson, Diego Pol, Jingmai O'Connor, Bhart-Anjan S. Bhullar, Gregory M. Erickson, Mark A. Norell, Andrew Orkney, Matthew C. Lamanna, Samir Zouhri, Justine Becker, Amanda Emke, Cristiano Dal Sasso, Gabriele Bindellini, Simone Maganuco, Marco Auditore, Nizar Ibrahim
Summary: Aquatic adaptations have evolved independently multiple times from terrestrial vertebrate ancestors, and this study reveals that bone density can be used as a reliable indicator of aquatic habits in extinct species.
Article
Geography, Physical
John C. Priscu, Jonas Kalin, John Winans, Timothy Campbell, Matthew R. Siegfried, Mark Skidmore, John E. Dore, Amy Leventer, David M. Harwood, Dennis Duling, Robert Zook, Justin Burnett, Dar Gibson, Edward Krula, Anatoly Mironov, Jim McManis, Graham Roberts, Brad E. Rosenheim, Brent C. Christner, Kathy Kasic, Helen A. Fricker, W. Berry Lyons, Joel Barker, Mark Bowling, Billy Collins, Christina Davis, Al Gagnon, Christopher Gardner, Chloe Gustafson, Ok-Sun Kim, Wei Li, Alex Michaud, Molly O. Patterson, Martyn Tranter, Ryan Venturelli, Trista Vick-Majors, Cooper Elsworth
Summary: The SALSA Project used environmentally clean hot-water drilling to access Mercer Subglacial Lake in Antarctica, collecting various samples and observing the interactions among ice, water, sediment, rock, microbes, and carbon reservoirs. Data showed hydrodynamic water mixing between the borehole and lake, with little effect on the stratigraphy of surficial sediment cores from debris fall-out.
ANNALS OF GLACIOLOGY
(2021)
Article
Geography, Physical
Shane Sookhan, Nick Eyles, Syed Bukhari
Summary: This study employs quantitative analytical techniques to map and classify geological features such as drumlins and mega-scale glacial lineations (MSGLs). The findings suggest that these bedforms are erosional remnants of older sediments, and their formation is influenced by differential erosion. The analysis of a large dataset reveals distinct morphotypes and demonstrates the differences in frictional drag between different surface types.
QUATERNARY SCIENCE REVIEWS
(2022)
Article
Geography, Physical
Gustaf Peterson Becher, Mark D. Johnson
Summary: Research in southern Sweden on v-shaped subglacial landforms (murtoos) shows that they are composed of heterogeneous diamicts with strong fabrics interbedded with sorted sediments, indicating ductile deformation and liquefaction. The landforms are interpreted as being created by till deposition and sedimentation from meltwater with subsequent deformation, suggesting a stepwise formation including periodic deformation events. The model proposed is based on a dynamic subglacial meltwater system similar to processes observed on the Greenland ice sheet today.
Article
Geochemistry & Geophysics
J. J. Buffo, L. Ojha, C. R. Meyer, K. L. Ferrier, M. C. Palucis
Summary: The presence of valley networks on Mars provides evidence for the existence of liquid water on the planet's surface. The characteristics of these valleys suggest that they were formed by subglacial channels, indicating that ice sheets may have played a significant role in shaping the Martian landscape even in a cold climate.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geography, Physical
Ivar Orn Benediktsson, Nina Aradottir, Olafur Ingolfsson, Skafti Brynjolfsson
Summary: This study reconstructs paleo-ice streams in NE-Iceland based on subglacial bedform mapping, revealing key information on ice sheet dynamics and evolution.
Article
Mechanics
Aman G. Kidanemariam, Markus Scherer, Markus Uhlmann
Summary: In this study, the turbulent flow and sediment grain motion over a subaqueous sediment bed with two-dimensional transverse ripples were numerically investigated. The study provides novel insights into the spatial structure of the basal shear stress and its relation to the particle flow rate.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Geosciences, Multidisciplinary
P. A. Jarvis, K. A. Bacik, C. Narteau, N. M. Vriend
Summary: Fluid flow over a granular bed can lead to the formation of surface wave instability, causing the sediment bed profile to evolve from ripples to dunes. Experimental and numerical simulation results show that the initial dune growth rate scales approximately as u*5, indicating a strong relationship between dune evolution and friction velocity.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)