Article
Geography, Physical
Neal R. Iverson, Sarah E. Krueger, Chris Harding
Summary: The distribution of drumlin fields in the glacial zone contains important information about ice sheet dynamics. Drumlins were not formed beneath the southernmost margin of the Laurentide Ice Sheet, including the Des Moines Lobe, while they were present beneath the northern lobes. The absence of drumlins in the southernmost lobes may be due to the combination of surging and stagnation, while the presence of drumlins in the northern lobes is likely a result of climatically-forced ice advance.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
Emma Ownsworth, David Selby, Jeremy Lloyd, Paul Knutz, Sonke Szidat, John Andrews, Colm O'Cofaigh
Summary: A new study investigates the sediment core from central Baffin Bay to reconstruct the ice sheet history and sediment fluxes. Two dominant sediment/discharge sources, detrital carbonate and radio-genic felsic, are identified. The study also provides updated age constraints and further supports the theory of an ice shelf in northern Baffin Bay.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Geography, Physical
Shannon M. Hibbard, Gordon R. Osinski, Etienne Godin
Summary: Conspicuous Vermicular Ridge Features (VRFs) with unique morphology have been discovered along the coast of Dundas Harbour, Devon Island, Nunavut, Canada. These features are believed to be ring-ridge moraines formed by paraglacial processes, representing a first documentation of such features in Nunavut, Canada.
Article
Geography, Physical
Catherine A. Delaney, Kathryn Adamson, Lorna D. Linch, Stephen Davis, Stephen McCarron
Summary: This study utilizes high-resolution digital elevation models (DEMs) derived from airborne LiDAR, ground-penetrating radar (GPR) surveys, and sedimentological analyses to investigate the geomorphology and composition of ridges and mounds in the Brosna basin, central Ireland. The findings suggest that the hummocky topography is composed of fragmented mega-scale glacial lineations (MSGLs) overlain by groups of small ridges formed by subglacial till and sediment gravity flow deposits. The research indicates that the formation of these landforms reflects changes in ice sheet bed thermal/hydrological characteristics during deglaciation.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Geography, Physical
J. H. England, R. D. Coulthard, M. F. A. Furze, C. F. Dow
Summary: This study documents the deposition and chronological record of a massive ice shelf from the former Laurentide Ice Sheet. The ice shelf advanced and retreated over a span of about 400 years, and its catastrophic breakup coincided with rapid warming of the atmosphere and ocean. The findings suggest that current ice dynamics models may underestimate the sensitivity of similar margins in Antarctica to ongoing global warming, emphasizing the importance of this research for estimating future sea level rise.
QUATERNARY SCIENCE REVIEWS
(2022)
Article
Geochemistry & Geophysics
Mohamed S. Elhebiry, Mohamed Sultan, Abotalib Z. Abotalib, Alan E. Kehew, Peter J. Voice, Ibrahim Abu El-Leil
Summary: This study provides evidence for a Late Ordovician glacial origin of streamlined landforms in Arabia and reconstructs the Late Ordovician ice sheet. The results support the existence of a significant and dynamic ice sheet during the Late Ordovician period and provide new morphological constraints for paleo-climate models.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geography, Physical
J. Goslin, P. Bernatchez, R. L. Barnett, B. Hetu, D. Didier, C. Beland, J. Dube
Summary: Beach-ridge systems are widely distributed worldwide and can serve as valuable archives for studying sea-level changes and coastal processes. This study examines beach-ridge complexes on Anticosti Island, Canada and produces new sea-level data that contribute to a better understanding of isostatic dynamics in the region. The study also reveals significant misfits between observations and GIA models, leading to refinements on the past ice sheet and melting history, as well as rheological characteristics of the St-Lawrence valley. Additionally, the study provides insights into paleo-oceanographic changes through the analysis of the beach-ridges.
QUATERNARY SCIENCE REVIEWS
(2023)
Review
Geosciences, Multidisciplinary
Jianghu Lan, Tianli Wang, Jibao Dong, Shugang Kang, Peng Cheng, Kang'en Zhou, Xingxing Liu, Yaqin Wang, Le Ma
Summary: This study reveals that the moisture conditions in northern Central Asia during the early Holocene were controlled by the position of the mid-latitude Westerlies, while persistent drought conditions during the middle Holocene were caused by the northward migration of these Westerlies. The recent southward movement has resulted in a relatively wetter Central Asia region.
EARTH-SCIENCE REVIEWS
(2021)
Article
Geography, Physical
Whyjay Zheng
Summary: This paper presents a new model to explain the response of glaciers to basal lubrication. By validating the model using data from 1996 to 1998, it was found that glaciers with lower Peclet number and product of glacier speed and thickness gradient are more likely to accelerate over a 20-year period.
Article
Geography, Physical
Pierre-Olivier Couette, Jean-Francois Ghienne, Patrick Lajeunesse, Jerome van der Woerd
Summary: The Laurentide Ice Sheet (LIS) was the largest ice sheet in the Northern Hemisphere during the last glacial cycle. Its demise had significant effects on global climate and sea-level changes. Understanding the relationship between ice sheets and climatic events is crucial for predicting future ice sheet melting and its impact on sea-level changes.
JOURNAL OF QUATERNARY SCIENCE
(2023)
Article
Geography, Physical
Jacob Downs, Jesse Johnson
Summary: This study simulates the rapid retreat of Upernavik Isstrom marine glacier and investigates the mechanisms driving glacier retreat. The results show that a glacier undergoing rapid retreat is as sensitive to perturbations in the balance of forces as a glacier in steady state. Additionally, the study highlights the significance of meltwater-forced decoupling in glacier dynamics.
JOURNAL OF GLACIOLOGY
(2022)
Article
Geography
Benjamin J. Stoker, Martin Margold, Duane Froese
Summary: During the Last Glacial Maximum, the Mackenzie Mountains region was affected by three different ice sources - the Laurentide Ice Sheet, the Cordilleran Ice Sheet, and independent montane glaciers. The thinning of the Laurentide-Cordilleran ice saddle led to rapid sea level rise events and influenced the deglaciation process in the north. A new glacial geomorphological map covering over 220,000 km(2) has been presented for the Mackenzie Mountains region, which will serve as a foundation for future studies on the ice extents and dynamics.
Article
Geography, Physical
Tomasz Salamon
Summary: This study presents a sedimentological and structural analysis of a push-moraine formed in front of the Scandinavian Ice Sheet margin. The study focuses on the Glubczyce Plateau at the forefield of the East Sudetes Mountains. The push-moraine formation is strongly influenced by the substratum's topography and geology. The resistant Palaeozoic bedrock provides a rigid surface along which unconsolidated sediments are pushed in front of the advancing ice sheet. The deformation of the moraine is induced by compression forces developed within the ice sheet margin moving against a reversed bedrock slope. A complete understanding of the push-moraine formation and its paleoclimatic significance requires a three-dimensional analysis of the ice sheet behavior over a larger area.
Article
Multidisciplinary Sciences
Lars Max, Dirk Nuernberg, Cristiano M. Chiessi, Marlene M. Lenz, Stefan Mulitza
Summary: This study provides solid evidence for the rapid subsurface ocean warming preceding Heinrich Events in the subpolar Atlantic. The accumulation of ocean heat near the critical depth is identified as the trigger for the melting of marine-terminating portions of the Laurentide Ice Sheet. The study also suggests that weaker ocean circulation in the future may lead to accelerated interior-ocean warming, which is critical for the stability of modern Arctic glaciers and the freshwater budget of the North Atlantic.
NATURE COMMUNICATIONS
(2022)
Article
Geography, Physical
Spruce W. Schoenemann, Mana M. Bryant, Will B. Larson, Lee B. Corbett, Paul R. Bierman
Summary: The study suggests that alpine glaciers in the Pioneer Mountains of Montana had similar initial deglaciation timing as the northwestern Yellowstone glacial system and the northern Montana ice cap, indicating a stronger ability to maintain full ice extent closer to the Laurentide Ice Sheet (LIS) margin.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Geography, Physical
A. Securo, C. Del Gobbo, L. Rettig, S. Pillon, A. De Luca, D. Fontana, E. Benedetti Fasil, R. R. Colucci
Summary: Small glaciers in temperate mountain regions have experienced significant reduction and unprecedented melt rates in recent years. Some glaciers have transitioned from clean ice to debris-covered or even rock glaciers. This study examines the surface elevation change of the Popera Alto glacier in the Sesto Dolomites using LiDAR and Structure from Motion surveys, and analyzes its evolution in terms of surface cover and geomorphic processes. The glacier has lost an average of 0.35 m water equivalent per year over the past 16 years, with active modification of its surface cover by geomorphic processes. The role of debris and local topography feedback has allowed the resilience of the glacier, leading to a marked difference between the current environmental equilibrium line altitude (envELA) and the effective ELA (effELA) of the glacier.
Article
Geography, Physical
Zhenzhen Yan, Yaolin Shi, Lili Kang, Xiangtao Fan
Summary: This study proposes a quantitative regional deformation model based on global positioning system (GPS) data to quantitatively analyze the morphological evolution of rivers in the Three Rivers Region. It finds that tectonic deformation phases significantly control regional landscape development and drainage features.
Article
Geography, Physical
Said Mukhtar Ahmad, Nitheshnirmal Sadhasivam, Mona Lisa, Luigi Lombardo, Mustafa Kemal Emil, Amira Zaki, Cees J. Van Westen, Islam Fadel, Hakan Tanyas
Summary: In this study, we investigated a large slow-moving landslide in Northern Pakistan, using Interferometric Synthetic Aperture Radar (InSAR) analysis. Our results showed that the crown of the landslide is moving faster than the surrounding regions, while the footslope experienced high deformations. We discussed the possible roles of meteorologic and anthropogenic factors in causing these deformations.
Article
Geography, Physical
Shuang Bian, Xibin Tan, Yiduo Liu, Suoya Fan, Junfeng Gong, Chao Zhou, Feng Shi, Michael A. Murphy
Summary: The Yarlung River's drainage divide is primarily moving north due to variations in precipitation across the Himalayas. The Gangdese drainage divide shows predominantly northward and southward migration, controlled by base-level rise and downstream influences. The presence of north-trending rifts separates the drainage divides into five zones, each with a distinct migration pattern.
Article
Geography, Physical
Joon-Young Park, Seok Yoon, Deuk-Hwan Lee, Seung-Rae Lee, Hwan-Hui Lim
Summary: This study developed a multiple-regression model to estimate site-specific average growth rates of debris flow events. The proposed model was validated through a case study and showed reasonable predictions of debris flow velocities and heights.
Article
Geography, Physical
Nicholas Reilly Mccarroll, Arnaud Temme
Summary: New geochronological data from hillslope boulder armor in the Flint Hills reveal the rates and timing of lateral retreat in the landscape. Surfaces of limestone boulders dating back to the Pleistocene era were found, and the ages of the hillslope armor increased with distance from the limestone bench. The estimated rate of lateral retreat in this landscape is 0.02 mm/yr.
Article
Geography, Physical
Xinbo Yao, Yuntao Tian
Summary: By studying the Longmenshan-Minshan drainage divide, we found that it has reached a dynamic steady state, indicating a balance between erosion and rock uplift. This study also reveals the process of formation and evolution of the divide and raises questions about the effectiveness of divide migration metrics.
Article
Geography, Physical
Junhui Yu, Pin Yan, Yanlin Wang, Guangjian Zhong, Changliang Chen
Summary: The seafloor mounds in the Chaoshan Depression of the South China Sea are identified as mud volcanoes, with fluids coming from underlying mud-fluid diapirs. The hydrocarbon gases feeding the mud volcanoes and diapirs are reasoned to originate from deep Mesozoic source rocks, indicating significant Mesozoic hydrocarbon potential in the Chaoshan Depression.
Article
Geography, Physical
Marius Huber, Luc Scholtes, Jerome Lave
Summary: This paper investigates the relationships between hillslope stability and fabric anisotropy of brittle rock materials and the implications for landscape shaping. It explores the different stability modes and movement characteristics of anisotropic materials, and demonstrates the significant control of material anisotropy on landscape shaping.
Article
Geography, Physical
Shubhra Sharma, Anil D. Shukla
Summary: The study investigates the relationship between glacial dynamics and lake sedimentation during the mid-Holocene climate variability in the Southern Zanskar ranges. It utilizes geomorphological disposition, elemental geochemistry, and optical chronology of relict lake sediment to reconstruct the pattern of minor glacier responses to climate variability. The results indicate six centennial to millennial-scale climatic phases, with warmer phases represented by decreased mineralogical fine grain flux and increased coarse grain flux. The study highlights the potential of relict lake sediment and para/peri-glacial landforms in understanding glacial dynamics and climate change during the Holocene.
Article
Geography, Physical
Jean-Francois Bernier, Sydney W. Meury, Patrick Lajeunesse
Summary: In this study, an approach combining various data and observation methods was proposed to improve the monitoring of landfast ice dynamics and its geomorphic impact on sedimentary systems. The results demonstrate the ability of the approach to accurately measure interannual variations in landfast ice and constrain geomorphic changes. Additionally, the study found a strong relationship between the severity of freezing seasons and the response of landfast ice to hydrometeorological events, with different geomorphic responses observed under different winter conditions.
Article
Geography, Physical
Heping Shu, Fanyu Zhang
Summary: This study investigates the relationship between susceptibility of soil-water hazards and human activities, geoheritage sites in the Loess Plateau, China. Landslide and gully erosion susceptibility were obtained using gradient boosting and support vector machines, and a hazard matrix was formed to couple landslide and gully erosion susceptibility. The study found different trends in the magnification times of soil-water hazards chain under different scenarios.
Article
Geography, Physical
Guangqiang Qian, Zhuanling Yang, Xuegang Xing, Zhibao Dong, Youyuan Guo
Summary: Granule ripples are aeolian landforms armored against erosion by coarse grains. This study investigates their seasonal morphological evolution and migration in the Sanlongsha Dune Field. The findings show that wind events, especially those exceeding the threshold velocities of coarse grains, significantly influence the morphodynamics of granule ripples. The study highlights the importance of considering the reptation and saltation of coarse grains in future research on granule ripples.