Journal of Geophysical Research: Earth Surface最新文献_第4页

Floodplain Vegetation Density Effects on Meandering Channel Flow Patterns and Channel-Floodplain Hydraulic Exchange 河漫滩植被密度对曲流河道流型和河漫滩水力交换的影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-22 DOI: 10.1029/2024JF008038

Daniel C. White, Ryan R. Morrison, Peter A. Nelson

{"title":"Floodplain Vegetation Density Effects on Meandering Channel Flow Patterns and Channel-Floodplain Hydraulic Exchange","authors":"Daniel C. White, Ryan R. Morrison, Peter A. Nelson","doi":"10.1029/2024JF008038","DOIUrl":"10.1029/2024JF008038","url":null,"abstract":"Channel-floodplain flow interactions are strongly influenced by riparian vegetation characteristics. However, due to the complicated relationships among floods, vegetation, and channel morphodynamics, these interactions are poorly understood. In this study, we investigate the influence of the density of rigid floodplain vegetation on flow in meandering compound channels through a series of laboratory flume experiments. We observed the flow field in a scaled meandering compound channel with three floodplain vegetation densities (0, 3, and 12.1 stems/m2) and three floodplain relative depths. We measured the 3D components of velocity using an ADV at 10 cross sections through one half-meander and across the water surface using LSPIV. We found that increased floodplain vegetation density promotes flow steering and enhanced secondary currents within the channel. High-density vegetation attenuates channel-floodplain exchange by over 60% compared to the bare floodplain condition at high floodplain relative depth. We describe three mechanisms that drive complicated flow structure within the channel: (a) helical flow arising from channel planform and bed topography, (b) a horizontal shallow mixing layer at bankfull height over the channel, and (c) a vertical shallow mixing layer at bankfull height along the channel-floodplain interface. We find that increased vegetation density enhances mechanisms 1 and 3 and mechanism 2 leads to less coherent secondary flow with an unvegetated floodplain. These findings suggest that riparian vegetation is a strong driver of meandering channel flow dynamics, which should be considered for best practices in riverscape management.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geotechnical Stability Analysis of Dune Face Erosion by Waves 沙丘表面波浪侵蚀的岩土稳定性分析

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-22 DOI: 10.1029/2024JF008160

S. Conti, K. D. Splinter, I. L. Turner

{"title":"Geotechnical Stability Analysis of Dune Face Erosion by Waves","authors":"S. Conti, K. D. Splinter, I. L. Turner","doi":"10.1029/2024JF008160","DOIUrl":"10.1029/2024JF008160","url":null,"abstract":"Predicting the extent of wave-driven dune erosion under wave impact and elevated water levels will improve our ability to safeguard the livelihood of ecosystems, communities and infrastructure living behind sandy beaches worldwide. However, the geophysical processes leading to time-dependent dune face failures are still not fully understood. Here, physical laboratory experiments are used to inform a coupled groundwater and limit equilibrium slope stability model to explore dune face stability. The model incorporates a spatially time-varying phreatic (or “water table”) surface and the associated changes in pore water pressure due to wave runup to highlight three key physical processes leading to geotechnical dune face failure during wave-driven erosion. First, results from numerical modeling indicate that wave runup impacting the dune face has a destabilizing effect due to excess pore water pressure during downrush. Second, dune face instability during saturated pore water conditions occurs due to excess pore water pressure and the lack of apparent cohesion resulting from the super-elevated water table present inside the dune face. Instability is further exacerbated by wave runup reaching the dune and further elevating the phreatic surface. Third, an important feature in the timing and resiliency of the dune face under wave attack is the location and temporal evolution of the slumped sand post a failure event. The unconsolidated slumped sand acts to temporarily protect the base of the dune from direct wave attack until it is eroded away using swash processes.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008160","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Glacier Changes in the Alps From the GRACE and GRACE Follow-On Missions (2002–2023) 从GRACE和GRACE后续任务（2002-2023）观察阿尔卑斯山的冰川变化

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-21 DOI: 10.1029/2024JF008182

S. Liu, R. Pail

{"title":"The Glacier Changes in the Alps From the GRACE and GRACE Follow-On Missions (2002–2023)","authors":"S. Liu, R. Pail","doi":"10.1029/2024JF008182","DOIUrl":"10.1029/2024JF008182","url":null,"abstract":"In this paper, time-variable gravity field data from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions are used to quantify glacier mass changes in the Alps from 2002 to 2023. We employ a new method that utilizes the vertical surface displacement data to correct the glacial isostatic adjustment and tectonic uplift signals. This approach increases the mass change signal by 0.8 ± 0.1 Gt/yr. We further include two land hydrology models, Global Land Data Assimilation System Version 2.1 (GLDAS V2.1) and the land component of the Fifth Generation European Reanalysis (ERA5-Land), to correct the gravity data for hydrological signals. We demonstrate three different forward modeling-derived schemes to recover the signals from GRACE/GRACE-FO observations. Our results, when compared with the annual glacier mass balance from the World Glacier Monitoring Service, indicate that among the three experimental schemes, the global unconstrained forward modeling algorithm demonstrates the best performance in estimating glacier mass change in the Alps. Overall, applying our new vertical deformation correction method, we find that the total glacier mass loss rate in the Alps is −2.4 ± 0.8 Gt/yr using GRACE/GRACE-FO Level-2 data. Our results identify a 3-month lag between land surface temperature and glacier mass variations, which is related to the response of glacier melt and accumulation to temperature variations.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008182","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144671992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Similarity Law for Sandy Tsunami Deposits 沙性海啸沉积物的相似定律

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-18 DOI: 10.1029/2024JF008244

K. Yamashita, D. Sugawara, K. Goto, T. Ishizawa, T. Takahashi

{"title":"A Similarity Law for Sandy Tsunami Deposits","authors":"K. Yamashita, D. Sugawara, K. Goto, T. Ishizawa, T. Takahashi","doi":"10.1029/2024JF008244","DOIUrl":"10.1029/2024JF008244","url":null,"abstract":"Herein, a basic relation between tsunami size and sandy tsunami deposits, i.e., a similarity law for sandy tsunami deposits, was derived by integrating the advantages of empirical and theoretical inverse modeling and forward modeling. Two concepts were introduced: (a) defining the involved deposition distance (Ld) based on the pickup and settling of sediments during the tsunami run-up and (b) systematically deriving the relation between the physical quantities involved in tsunami deposit formation and tsunami height based on the tsunami sediment transport theory. Similarity law derivation involved considering continuous sediment pickup at the sediment source. The effects of various uncertainties associated with tsunami deposits, such as those related to topography, land use, and sediment properties, were aggregated into a relation coefficient a*. Consequently, two similarity law models—a low-order model that does not consider the change in suspended-load concentration due to the relative advection of sediment to subsequent flows and a high-order model that considers this aspect—were proposed. If a* was determined based on known information (e.g., relation between the Ld and inundation distance of a known tsunami event), the similarity law could be applied to giant tsunamis without determining the parameters related to uncertainties. To verify the concepts, the results obtained using the similarity law were compared with those from numerical simulations reflecting the assumptions imposed on the similarity law. The similarity law was found to be reasonable. Overall, this research is expected to contribute to more accurate estimation of the sizes of past giant tsunamis and similar future tsunamis.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008244","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Near Steady Late Pleistocene Tropical Denudation Rates in SW Madagascar 马达加斯加西南部近稳定的晚更新世热带剥蚀率

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-11 DOI: 10.1029/2024JF008147

Etienne Large, Julien Charreau, Pierre-Henri Blard, Germain Bayon, Eduardo Garzanti, Bernard Dennielou, Gwenaël Jouet, Natalia Vazquez Riveiros, Jacques Giraudeau, Laurie Reisberg, Aimeryc Shcumacher, Alfred Andriamamonjy, Amos Fety Michel Rakotondrazafy

{"title":"Near Steady Late Pleistocene Tropical Denudation Rates in SW Madagascar","authors":"Etienne Large, Julien Charreau, Pierre-Henri Blard, Germain Bayon, Eduardo Garzanti, Bernard Dennielou, Gwenaël Jouet, Natalia Vazquez Riveiros, Jacques Giraudeau, Laurie Reisberg, Aimeryc Shcumacher, Alfred Andriamamonjy, Amos Fety Michel Rakotondrazafy","doi":"10.1029/2024JF008147","DOIUrl":"10.1029/2024JF008147","url":null,"abstract":"Denudation is a key parameter controlling the evolution of the Earth's surface, the production of soils, the stability of relief, or the long-term evolution of climate. Climate fluctuations conversely have a strong impact on denudation, but these complex feedback mechanisms are still under-constrained. To better predict future changes that will affect our habitat and understand the links between climate and denudation, precise quantification of paleo-denudation rates is required. In this work, we measure cosmogenic radionuclides (10Be) in turbidites of a well-dated marine sedimentary core recovered in the Mozambique Channel to provide a 900-ka long near-continuous record of paleo-denudation rates over the 100-ka climatic cycles. Neodymium isotopes and heavy mineral analysis were used to provide constraints on the provenance of terrigenous sediments exported from Madagascar to the studied site and show that temporal variations in sediment provenance are limited and decoupled from climatic cyclicity. Our 10Be-based paleo-denudation rates are in the same order as modern rates, ranging from 17.4 ± 5.8 mm/ka to 73.9 ± 29.4 mm/ka (1 standard deviation), and do not show major variations through the Middle and Late Pleistocene. Importantly, we did not identify a systematic significant impact of glacial/interglacial cyclicity on denudation rates. Denudation of this subtropical island may instead have been controlled by variability of monsoon intensity associated with shifts in the Inter Tropical Convergence Zone, but this interpretation remains speculative at this stage as it cannot be recorded within the resolution of cosmogenic-derived denudation rates.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008147","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Controlling Factors on Water and Sediment Partitioning at Deltaic Bifurcations 三角洲分岔区水沙分配的控制因素

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-09 DOI: 10.1029/2024JF008152

Gabriele Barile, Paola Passalacqua, Siyoon Kwon, Marco Tubino

{"title":"Controlling Factors on Water and Sediment Partitioning at Deltaic Bifurcations","authors":"Gabriele Barile, Paola Passalacqua, Siyoon Kwon, Marco Tubino","doi":"10.1029/2024JF008152","DOIUrl":"10.1029/2024JF008152","url":null,"abstract":"Bifurcations in river-dominated deltas are the main actors in the routing of water and sediments throughout the fluvial network. In spite of previous acknowledgments of their importance, we still lack a comprehensive framework on how bifurcation geometry affects water and sediment partitioning. To investigate this issue, we first combine previously calibrated 2D hydrodynamic simulations on the Wax Lake Delta with a Lagrangian particle-tracking model, quantifying the partitioning of water and sediments with different buoyancy at five bifurcations and their correlations with differences in channel width, branching angle and inlet bed elevation between the downstream branches. We compare the sediment partitioning at bifurcations with available field data to validate our methodology. We then employ the same modeling tools on a simplified geometry, whose geometrical and hydraulic features resemble those of the bifurcations in the Wax Lake Delta. Model results show that the branching angle does not affect the partitioning of water and sediments. The combined effect of asymmetries in the channel width and inlet bed elevation is captured by a simple linear formula that accurately estimates the partitioning of water at bifurcations returned by the 2D calibrated hydrodynamic simulations. Our results also highlight the key role played by transverse gradients in the bathymetry of the upstream channel in determining the partitioning of sediments, suggesting that deeper portions of the cross-section of the upstream channel can cause a proportionately larger fraction of sediments with a larger Rouse number to be routed toward the corresponding bifurcate.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008152","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144581983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interplay of Freeze-Thaw Cycles and Avalanche Impact on Glacial Landslide-Debris Flow Geohazard Chain in the Southeastern Tibetan Plateau 冻融循环与雪崩对青藏高原东南部冰川滑坡-泥石流地质灾害链的影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-07 DOI: 10.1029/2024JF008052

Taosheng Huang, Tengfei Wang, Limin Zhang, Dalei Peng, Ping Shen

{"title":"Interplay of Freeze-Thaw Cycles and Avalanche Impact on Glacial Landslide-Debris Flow Geohazard Chain in the Southeastern Tibetan Plateau","authors":"Taosheng Huang, Tengfei Wang, Limin Zhang, Dalei Peng, Ping Shen","doi":"10.1029/2024JF008052","DOIUrl":"10.1029/2024JF008052","url":null,"abstract":"Southeast Tibet suffers increasing hyper-mobility cascading geohazards, especially during the warm season. The glacial debris flow on 10 September 2020 in the Zelunglung Basin, transformed from a moraine landslide, exemplifies such geohazards, yet the landslide initiation or evolution process remained obscure. Literature deduced rock-ice avalanche can trigger moraine landslides and freeze-thaw cycles modify moraine deposit integrity, but their interplay effect is rarely touched. Here, we combined satellite remote-sensing, post-event investigation and multi-physics modeling to reveal these questions. Field investigations and satellite data suggest that a small rock-ice avalanche likely triggered a moraine landslide, setting off the cascading event with the evolution process as a small rock-ice avalanche (0.45-Mm3) → impact on moraine deposit → moraine landslide (1.14-Mm3) → glacial debris flow, where avalanching-moraine landslide is the key link, regarding the volume amplifying effect. Utilizing multi-physics modeling, we explored the interplay of freeze-thaw cycles and avalanche impacts on moraine deposit stability. Numerical results validate the avalanche as a primary instigator. Under such avalanche impacts, moraine deposits predominantly fail in warm seasons. Elevated water content from ice melting within moraine deposits, intensified during thawing and restrained during freezing, creates a conducive environment for excess pore pressure build-up and subsequent liquefaction when subjected to avalanche stresses, leading to transformation to debris flows. Thus, the seasonal freeze-thaw cycles exhibit a control effect on the key link and the whole chain. Our findings suggest increasing attention to potential locations of rock-ice avalanches through earth observation and seismic monitoring systems for hazard prediction and risk mitigation, particularly in warm seasons.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geomorphic Response to Extreme Flooding in Northern Yellowstone National Park, USA 美国黄石国家公园北部极端洪水的地貌响应

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-05 DOI: 10.1029/2024JF008215

Zachary P. DeLuca, Andrew C. Wilcox, Lyman P. Persico

{"title":"Geomorphic Response to Extreme Flooding in Northern Yellowstone National Park, USA","authors":"Zachary P. DeLuca, Andrew C. Wilcox, Lyman P. Persico","doi":"10.1029/2024JF008215","DOIUrl":"10.1029/2024JF008215","url":null,"abstract":"Understanding and predicting flood-induced geomorphic change, and the relative influences of fluvial forces and valley-bottom geometry on system response, are persistent quandaries in geomorphic-process studies. We combined field surveys, remote sensing, and hydraulic modeling to assess the geomorphic effects of the June 2022 flooding in northern Yellowstone National Park, in the western United States, which was by far the largest recorded flood at nearby gaging stations and caused extensive damage to park infrastructure. We evaluate geomorphic response relative to two ways of calculating the hydraulic forcing produced by the flood: unit stream power and impulse, a metric that incorporates flow duration, grain size, channel-bed slope, flood depth, and a threshold based on threshold channel theory. Measurements of pre- and post-flood active-channel width change captured the geomorphic response associated with deposition- and erosion-related channel migration. The geomorphic response to flooding showed substantial variability. Notable lateral channel erosion in some cases occurred in areas of high flow strength, such as high-gradient reaches, but elsewhere was concentrated along erodible channel margins and/or downstream of confluences, where calculated flow forces were unremarkable. Channel widening was greater in partially confined reaches than in unconfined or confined reaches, and channel areas of extensive deposition were associated with decreases in valley-bottom confinement. Low-gradient, unconfined reaches where flood flow spread across floodplains showed little evidence of the passage of a historic flood. As climate change increases the propensity for hydroclimatic extremes and events such as the Yellowstone flood, investigation of links between flood forcings and geomorphic response is particularly important.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144558008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Predicting the Three-Dimensional Stratigraphy of an Ice Rise 预测一次冰升的三维地层学

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-04 DOI: 10.1029/2024JF007924

A. C. J. Henry, C. Schannwell, V. Višnjević, J. Millstein, P. D. Bons, O. Eisen, R. Drews

{"title":"Predicting the Three-Dimensional Stratigraphy of an Ice Rise","authors":"A. C. J. Henry, C. Schannwell, V. Višnjević, J. Millstein, P. D. Bons, O. Eisen, R. Drews","doi":"10.1029/2024JF007924","DOIUrl":"10.1029/2024JF007924","url":null,"abstract":"Ice rises located in ice shelves around Antarctica act as pinning points, impeding the flow of ice in ice shelves and in the upstream ice sheet. Ice rises preserve records of past climate and associated changes in ice flow in their stratigraphy. Typically, the flow of ice in ice rises is characterized by both converging and diverging patterns, experiencing transitions from contact with bathymetric features to floating on the ocean. In this study, we develop a three-dimensional ice flow model that is capable of simulating the internal stratigraphy of ice rises. The modeled stratigraphy can be compared with observed stratigraphy inferred from ground-penetrating radar observations. The model simulates three-dimensional ice flow described by the Stokes equations and evolution of ice temperature described by an advection-diffusion equation that impacts the non-linear ice rheology. We use our model to simulate the observed stratigraphy of Derwael Ice Rise in Dronning Maud Land, East Antarctica. Our results show a close agreement with the observed ice stratigraphy and suggest that the ice at 5% above the base is approximately 8,000 years old. Our new model enables us to relate the observed ice-rise stratigraphy to the ice flow and its changes.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF007924","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144551085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seismic Evidence of Impact Breccia and Unlithified Sediments Under Hiawatha Glacier 海瓦塔冰川下冲击角砾岩和未岩化沉积物的地震证据

IF 3.8 2区地球科学

Journal of Geophysical Research: Earth Surface Pub Date : 2025-07-01 DOI: 10.1029/2024JF008247

Rishi Chandra, Kiya L. Riverman, Daniella N. DellaGiustina, Erin C. Pettit, Nicholas C. Schmerr, Georgia Carroll, Veronica J. Bray, S. Hop Bailey

{"title":"Seismic Evidence of Impact Breccia and Unlithified Sediments Under Hiawatha Glacier","authors":"Rishi Chandra, Kiya L. Riverman, Daniella N. DellaGiustina, Erin C. Pettit, Nicholas C. Schmerr, Georgia Carroll, Veronica J. Bray, S. Hop Bailey","doi":"10.1029/2024JF008247","DOIUrl":"10.1029/2024JF008247","url":null,"abstract":"Hiawatha Crater in northwest Greenland is one of only two putative impact craters under an ice sheet. Hiawatha therefore offers a rare proxy for understanding the interactions between active glacial dynamics and impact craters on other planetary bodies. Here we characterize Hiawatha's subglacial environment, presenting the results of two active-source seismic experiments and interpreting them in concert with previous radar sounding analysis. Seismic reflectivities at a site with a single basal radar reflector are consistent with a substrate of impact melt-bearing breccia. At a site where radar sounding revealed a porewater reflector 10–15 m below the base of the ice sheet, our seismic results are consistent with a substrate of unlithified sediments. We propose a model where supraglacial water supplies heat for basal melting, leading to rain–out of unconsolidated sediment from debris-rich basal ice (fringe) and permitting a permeable porewater-bearing basal layer to persist without consolidating.","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"130 7","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF008247","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0