Geomorphology最新文献

{"title":"Fluvial terraces of the lower Mekong River reflect quaternary global sea level fluctuations as a likely response to Himalayan glacial/deglacial runoff","authors":"P.A. Carling ,&nbsp;L. Meshkova ,&nbsp;A. Srivastava ,&nbsp;T. Kinnaird ,&nbsp;Z. Ding ,&nbsp;R. Robinson ,&nbsp;S.E. Darby ,&nbsp;X. Fan","doi":"10.1016/j.geomorph.2025.109756","DOIUrl":"10.1016/j.geomorph.2025.109756","url":null,"abstract":"<div><div>Knowledge of the Quaternary history of the lower Mekong, the major river within Cambodia, is basic. Herein we advance understanding by investigations of river terrace topographic expression and stratigraphy. Satellite images, digital elevation models and fieldwork have been used to define the terrace elevations and extent. Three terrace levels can be recognized, separated in the vertical, lateral and temporal dimensions by distinctive sedimentary signatures. Strath surfaces and alluvial cover have been dated using terrestrial cosmogenic and optical luminescence protocols. The highest level (T1: notionally +100 m above present sea level) is a discontinuous, degraded, bedrock strath with a patchy veneer of well-weathered fluvial cobble gravel. T1 is younger than a regionally significant meteorite impact ~800 ka (Marine Isotope Stage<span><span>²</span></span> 20), and older than basalt flows on its surface (600 ka?). The T1 level was abandoned before 99.42 ± 7.52 ka (the end of the glacial MIS 5d), as the river incised in response to a rapidly falling sea level, to form a broad continuous strath terrace (level T2) exhibiting a thin alluvial cover, between 70 m and 40 m above sea level. The T2 terrace is composed of partially lateritic, interlayered, sand and gravel beds lying above weathered bedrock (blue/red clay). The basal deposits on the T2 level date to 70.65 ± 5.13 ka, following a sea level rise to a short-lived elevation of around +30 m around 80 ka (MIS 5a). The T2 level was progressively down cut between 57.73 ± 5.31 ka and 38.66 ± 2.40 ka (MIS 3). Steadily falling sea level sustained MIS 3 incision which reached <em>c</em>., 10 m above the modern river level <em>c</em>., 33.03 ± 3.09 ka, before the offshore minimum in sea level, <em>c</em>., 23 ka, i.e., towards the end of the Last Glacial Maximum. A loam-rich sandy terrace (T3; <em>c</em>., 0.45 ka (MIS 1)) is developed locally at c., +20 m above sea level. The timing of abrupt incisions, leading to the abandonment of the T1 and T2 levels, coincide with the onset of cool glacial stadials and falls in global sea level, whilst initial aggradation on the T2 level broadly can be associated with MIS 4. Despite a reduction in the contribution of glacial runoff from the Himalaya and Tibet towards the end of the Pleistocene, channel narrowing from T1 onwards has sustained the erosive power of the river, such that the rate of incision has only slowed within the Holocene.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109756"},"PeriodicalIF":3.1,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823833","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}

{"title":"Morphological characteristics and evolution processes of the blowouts on fine-grain armored paleodunes in the eastern Qaidam Basin, Tibetan Plateau","authors":"Dehua Xu ,&nbsp;Ping An ,&nbsp;Jiyan Li ,&nbsp;Lupeng Yu","doi":"10.1016/j.geomorph.2025.109752","DOIUrl":"10.1016/j.geomorph.2025.109752","url":null,"abstract":"<div><div>Blowouts are essential wind-erosion landforms, representing the reactivation of fixed dunes and initiation of desertification. Blowouts occurring on stabilized paleodunes have received less attention than the more common, smaller and shallower blowouts within loose sand surfaces. We explored the geomorphic characteristics, evolutionary processes, and influencing factors of a unique type of blowout in the eastern Qaidam Basin, Tibetan Plateau that forms on paleodunes armored with thick crusts of fine-grained loess or fluvial sediments. Altogether, 1569 blowouts were mapped and analyzed on Google Earth and 24 blowouts were studied in the field. The presence of hard crusts, along with associated undercutting-collapsing expansion model, contributes to their distinct morphological features such as steep sidewalls, sharp rims, irregular shapes, and diverse sand lobe types. These blowouts, with prolonged evolutionary cycles at centennial to millennial scales, are significantly larger sizes than active dune blowouts and generate substantial dust emissions. Blowout shapes gradually become more regular approaching ellipticity with their orientations progressively aligning with the prevailing sand-driving wind direction. Blowout lengths were found to extend faster than their widths that in turn widen faster than their depths. In addition, their areas and lengths altogether increase faster than those of their deposition lobes. The formation and evolution of this special type of blowout are mainly attributed to climatic, sedimentological, and morphological factors which are associated with the destruction of the crusts and release of paleodune sand. Beyond providing new insight into the broader mechanisms of wind erosion and desertification in the Tibetan Plateau, this study appears relevant for many terrestrial and planetary aeolian environments.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109752"},"PeriodicalIF":3.1,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816383","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}

{"title":"Spatio-temporal distribution of boulders along a debris-flow torrent assessed by UAV photogrammetry","authors":"Samikshya Dahal ,&nbsp;Fumitoshi Imaizumi ,&nbsp;Shoki Takayama","doi":"10.1016/j.geomorph.2025.109757","DOIUrl":"10.1016/j.geomorph.2025.109757","url":null,"abstract":"<div><div>Debris flows are a common geohazard in mountainous regions that pose a serious threat to people’s lives and property. Understanding the spatiotemporal variations in sediments within debris-flow channels is crucial for assessing the associated risks and implementing effective mitigation measures. This study aims to reveal the spatial distribution of boulders from initiation to deposition zones in the debris-flow torrent of the Ohya landslide in central Japan. In this study, we analyzed two debris flow and sediment supply seasons in a debris-flow torrent using unmanned aerial vehicle-based Structure from Motion (UAV-SfM) photogrammetry to capture aerial images. Multiple clipped orthomosaic images generated using SfM software were processed using BASEGRAIN software to obtain the granulometric properties of the top-view area of each particle. To check the accuracy of BASEGRAIN analysis, the particle size of boulders in the field was directly measured using a grid sampling technique. The BASEGRAIN analysis revealed that lower-resolution photographs were more suitable for detecting boulder-sized sediments (&gt;256 mm), closely matching the grid-sampling data. Conversely, higher-resolution photographs detect finer sediments better but are less accurate for boulders. Our analysis revealed significant differences in boulder distribution between the upper and lower catchments, with notable changes observed across different seasons. Transportation of fine sediments from the upper to lower catchments and deposition of boulder sediments in the lower catchment contributed to these variations. The correlation between changes in boulder ratio and digital elevation models (DEM) indicates the significance of depositional and erosional processes in boulder distribution; however, there is a lack of a clear connection between boulder ratio and slope gradient. This research provides an understanding of sediment transport and deposition processes of debris flow with the viewpoint of changes in boulder distribution.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109757"},"PeriodicalIF":3.1,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826010","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}

{"title":"Erosion and potential geological hazards chain in the East African Rift System controlled by volcanic sediments properties and geological structure","authors":"Zhijie Jia ,&nbsp;Penghui Ma ,&nbsp;Ruijun Jiang ,&nbsp;Quanzhong Lu ,&nbsp;Zhenjiang Meng ,&nbsp;Weiliang Huang ,&nbsp;Jianqi Zhuang ,&nbsp;Xinghua Zhu ,&nbsp;Yanqiu Leng ,&nbsp;Feiyong Wang ,&nbsp;Bingyao Huo ,&nbsp;Jianbing Peng","doi":"10.1016/j.geomorph.2025.109755","DOIUrl":"10.1016/j.geomorph.2025.109755","url":null,"abstract":"<div><div>The East African Rift System (EARS) hosts extensive unconsolidated volcanic sediments whose unique physicochemical characteristics interact with geological structure to drive erosion and geological hazard cascades. Focusing on the Central Kenyan Rift (CKR), this study integrates geotechnical testing, sediment property analysis, and geophysical imaging to decipher the mechanisms controlling erosion evolution and associated geological hazard chains. Key findings reveal: (1) Four characteristic erosional landforms (sinkholes, pipes, gullies, badlands) developed in CKR volcanic sediments; (2) Volcanic sediments exhibited high vulnerability indices with &gt;40 % macroporosity (&gt;32 μm), bimodal grain size distributions, and alkaline profiles with surface Na+/metal enrichment. (3) Electrical resistivity tomography (ERT) delineated the erosion-piping networks, while Shallow seismic exploration (SSE) identified the strata dislocation patterns comprising stratal fracturing, normal faulting, reverse faulting, and uplifts. (4) Synergistic coupling between sediment properties and geological structure governs erosion and potential geological hazards. This integrated study advances understanding of erosion mechanisms of volcanic sediments in rift-related geological hazard cascades, providing critical insights for infrastructure resilience and land-use planning in active tectonic settings.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109755"},"PeriodicalIF":3.1,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816382","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}

{"title":"Detrital zircon geochronology of river sands from the Salween River: Implications for sedimentary provenance and erosion pattern","authors":"Ziwei Zhao,&nbsp;Qiuwei Yin,&nbsp;Xilin Sun","doi":"10.1016/j.geomorph.2025.109754","DOIUrl":"10.1016/j.geomorph.2025.109754","url":null,"abstract":"<div><div>Erosion patterns are generally controlled by the interaction of internal tectonic forces and external surface process, including active tectonic processes, precipitation, hillslope steepness and human activities. Studying sediments in river systems helps us understand watershed erosion, contributing to our comprehension of landform evolution, climate change, and biodiversity. The Salween River is a significant international river in Asia, less disturbed by human activities than other large rivers such as the Yangtze River. In this study, we use zircon U-Pb dating and Hf isotopes of bedrocks and mainstream river sediment to reveal the relative sediment contribution of bedrock in the Salween River. The detrital zircon U-Pb ages and combined Hf isotopic data from the Salween River suggest that bedrocks from the middle section of the river contribute a large amount of sediments to the Salween River. This indicates that the middle section of the Salween River has been experiencing intense erosion. Potential impact factors such as human activities, climate, slope, lithology, and tectonism that may control distribution of erosion are considered. We suggest that the most important factor controlling intense erosion in the middle section of the Salween River is likely to be the hillslope steepness. We also suggest that the characteristic zircon U-Pb age distributions of the Salween River could be used to reconstruct paleo-drainage patterns in the southeastern Tibetan Plateau.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109754"},"PeriodicalIF":3.1,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829012","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}

{"title":"Deciphering sediment connectivity dynamic in traditional water-meadows (lameiros)","authors":"T. Bertocco ,&nbsp;T. de Figueiredo ,&nbsp;A. Paz-González ,&nbsp;A. García-Tomillo ,&nbsp;M. López-Vicente","doi":"10.1016/j.geomorph.2025.109750","DOIUrl":"10.1016/j.geomorph.2025.109750","url":null,"abstract":"&lt;div&gt;&lt;div&gt;&lt;em&gt;Lameiros&lt;/em&gt; are traditional man-made water-meadows located at the bottom of the valleys in northern Portugal and northwestern Spain. Although &lt;em&gt;lameiros&lt;/em&gt; act as hydrological and sediment accumulation regulators, this process has never been quantified in a spatially distributed manner (maps), nor have its temporal variations. For the first time, the role of &lt;em&gt;lameiros&lt;/em&gt; in sediment connectivity is calculated by using the aggregated index of sediment connectivity (AIC) in two medium-size ungauged headwater basins with permanent and seasonal streams. Index parameterization was done in detail, including field surveys to distinguish the type, in-use (&lt;em&gt;n&lt;/em&gt; = 21) or abandoned (&lt;em&gt;n&lt;/em&gt; = 78), of &lt;em&gt;lameiros&lt;/em&gt; and their water availability, well (&lt;em&gt;n&lt;/em&gt; = 89) or poor (&lt;em&gt;n&lt;/em&gt; = 10) irrigated. Different sedimentological scenarios that occur throughout the year were computed considering the net soil loss at the basin scale (target: watercourses; common conditions with the whole basin activated) and temporary accumulation in watercourses (target: outlet; dry conditions with sediment transport limited to the streams). The three erosive periods that happen during the year, i.e. high, medium and low rainfall erosivity, were simulated with long, average and short watercourses. Results of structural connectivity proved that the role played by each input (land-use, soil permeability, rainfall erosivity, slope gradient, drainage area, roughness of the terrain) on sediment connectivity strongly depended on the spatial location of each landscape unit regarding the selected target and not only on their own values. This fact explained the lower connectivity obtained in the abandoned &lt;em&gt;lameiros&lt;/em&gt; than that found in the in-use &lt;em&gt;lameiros&lt;/em&gt;. Map analysis indicated that during the dry period from May to September overland flow was restricted to the streams, sediment supply from slopes to &lt;em&gt;lameiros&lt;/em&gt; was limited and the temporarily accumulated sediment in &lt;em&gt;lameiros&lt;/em&gt; may be remobilized, while during the wet (January–April) and rainy (October–December) periods sediment supply from active slopes to &lt;em&gt;lameiros&lt;/em&gt; was high and sediment delivery from &lt;em&gt;lameiros&lt;/em&gt; to stream was relatively lower, acting as sedimentation-prone areas. Indeed, poor-irrigated &lt;em&gt;lameiros&lt;/em&gt; had greater connectivity than well-irrigated &lt;em&gt;lameiros&lt;/em&gt;. Connectivity of &lt;em&gt;lameiros&lt;/em&gt; with their contributing areas (target: &lt;em&gt;lameiros&lt;/em&gt;) was higher than that of the remaining land uses with the outlet and watercourses, proving the high sediment accessibility of this landscape feature. Index output performed well against available data of soil depth measured both in the &lt;em&gt;lameiros&lt;/em&gt; and slopes. Multi-target computation of structural and functional connectivity concluded that sedimentation in &lt;em&gt;lameiros&lt;/em&gt; prevailed against sediment delivery, although both processes occurred simultaneously throughout the year. ","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109750"},"PeriodicalIF":3.1,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807191","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}

{"title":"Geolandscapes of the Ciucaș Mountains (Eastern Carpathians, Romania) - the assessment of geomorphosites and development of geotourism","authors":"Laura Comănescu,&nbsp;Alexandru Nedelea,&nbsp;Cosmin Păunescu","doi":"10.1016/j.geomorph.2025.109753","DOIUrl":"10.1016/j.geomorph.2025.109753","url":null,"abstract":"<div><div>The main goal of this paper is to provide an inventory and evaluation of geomorphosites in order to show how valuable geoheritage is and to make geotourism possible. The analysed area is represented by the Ciucaș Mountains (Eastern Carpathians, Curvature Group, Romania), which are formed by flysch (limestones, conglomerates, and alternations of sandstones and clays), due to which different geomorphosites have developed (especially through differential erosion).</div><div>The research methodology aimed at two directions: the evaluation by its own method of the most important geomorphosites — 34 pieces — and the analysis by means of questionnaires of the tourists' opinions (50 respondents); and finally, the correlation of the results in order to identify the landforms to be capitalised at a higher level through geotourism. It was found that the geomorphosites that obtained the highest values at the evaluation (based on their own method, which had the criteria: scientific, aesthetic, cultural, economic value, management, and use) carried out are also the most well-known and appreciated by tourists (Tigăile Mici - 0.67; Tigăile Mici - 0.66; Ciucaș Peak - 0.65; Sfinxul Bratocei - 0.65; Babele la Sfat - 0.60). In this respect, the geotouristic map of the study area was created, and three geotouristic trails were developed and analysed from a quantitative (characterisation, longitudinal profiles) and qualitative point of view (morphometric parameters and evaluation — mean value). The three trails received symbolic names (“Fairy Tales Cliffs”, “Towers and Fangs, “ and “Great Altitudes”) in order to increase their geotouristic value.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109753"},"PeriodicalIF":3.1,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800392","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}

{"title":"Swash bar stability on a high-energy mesotidal beach","authors":"J.E. Cueto-Fonseca ,&nbsp;G. Herbst ,&nbsp;C. Winter","doi":"10.1016/j.geomorph.2025.109751","DOIUrl":"10.1016/j.geomorph.2025.109751","url":null,"abstract":"<div><div>Swash bars are intertidal bar systems characterized by a single, small, low-amplitude bar and trough, often displaying a rhythmic pattern along the shore with troughs converging into shore-normal rip channels. In this study, we assess the stability of swash bars on Spiekeroog North Beach—a high-energy mesotidal beach in the German North Sea—using high-frequency fixed-camera imagery and wave and water level records collected over &gt;100 days. Swash bar size fluctuations and migration rates were calculated and related to water level and wave heights. Three distinct states can be defined: dynamic equilibrium (migration ≤15 m/day, associated with fair-weather conditions), active migration (migration &gt;15 m/day, occurring under moderate to high energy levels), and no-bar states, typically following high-energy events such as storms. Additionally, bar creation and destruction patterns were analysed in relation to local hydrodynamic conditions. These findings were synthesized into a stability diagram, illustrating the likely behaviour of swash bars under specific wave and water level conditions.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"479 ","pages":"Article 109751"},"PeriodicalIF":3.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143790995","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}

{"title":"Knickpoint migration and transient landscapes on the continental margin of Northeastern Brazil","authors":"Genisson PANTA ,&nbsp;Antonio Carlos de Barros CORRÊA ,&nbsp;Pedro VAL ,&nbsp;Kleython de Araújo MONTEIRO","doi":"10.1016/j.geomorph.2025.109741","DOIUrl":"10.1016/j.geomorph.2025.109741","url":null,"abstract":"<div><div>The response of bedrock rivers to a sudden drop in base level is the widespread formation and upstream propagation of knickpoints. This process progresses to restore steady-state conditions. The timeframe between the onset and end of the disturbance is known as the transient state. In this study, we identify and discuss the distribution pattern, timing, and potential controls of knickpoints in the eastern seaboard of Northeast Brazil. We focused on the Capiá River basin, one of the largest tributaries of the lower São Francisco River. We carried out topographic analysis based on digital elevation models, field observations, numerical modeling of knickpoint retreat, and base-level fall rates using a linear inverse model. Using these techniques, we identified the imprint of the last regional base-level fall event in the São Francisco River, corresponding to the formation and the opening of its canyon. We estimated that the incision was at least 100 m deep. The knickpoints are of the slope-break type and exhibit a systematic spatial distribution pattern. They separate an upstream relict landscape with low relief from a downstream, high-relief sector initiated by the base level lowering. All knickpoints occur near the confluence of trunk streams at similar elevations, resulting in a clustered chi-profile pattern. Inferred total knickpoint recession is strongly dependent on the drainage area. Additionally, the numerical model indicates that the knickpoints are mobile and genetically related, and that the incision wave initiated sometime within the 10⁶ to 10⁷ years BP interval, with the best fit at or after 1.5 Ma BP, corresponding to a retreat velocity of 0.01 m/yr. These results are independently supported by the linear inversion model constrained by erosion rates from previous studies. Lastly, we hypothesize that the interplay between climate (i.e., erosion threshold), epeirogenic uplift, and Late Cenozoic tectonic adjustments is responsible for the transient state of the study area.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109741"},"PeriodicalIF":3.1,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816381","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}

{"title":"Towards an understanding of dynamics of blue-ice moraines: A case study in the Grove Mountains, East Antarctica","authors":"Guocheng Dong ,&nbsp;Feixin Huang ,&nbsp;Weijian Zhou ,&nbsp;Yunchong Fu ,&nbsp;Yan Li ,&nbsp;Feng Xian ,&nbsp;Chaolu Yi ,&nbsp;Marc W. Caffee ,&nbsp;Xiaohan Liu","doi":"10.1016/j.geomorph.2025.109749","DOIUrl":"10.1016/j.geomorph.2025.109749","url":null,"abstract":"<div><div>Knowledge regarding former behavior of the East Antarctic Ice Sheet (EAIS) is crucial for assessing global sea-level change and understanding the global climate system. Yet, it remains challenging to examine pre-Last Glacial Maximum (LGM) glacial histories of the EAIS due to the limitations of the traditional geologic records. Recent studies suggest that blue ice areas (BIAs) and associated deposits (e.g. supraglacial moraines) have a potential to overcome this problem. However, the relationship between blue-ice evolution and climate changes is not yet well examined. In this study, we investigate two types of BIAs in the Grove Mountains, EAIS, on the basis of surface exposure dating of erratic boulders and cobbles on blue-ice moraines at Mount Harding and Escarpment. Here, we present 27 new ages, including single (¹⁰Be; <em>n</em> = 10) and paired (¹⁰Be and ²⁶Al, <em>n</em> = 17) exposure-ages. The newly-obtained ages, along with previously-published ¹⁰Be data (<em>n</em> = 40), indicate that the studied BIAs have been relatively stagnant since the LGM, and that blue-ice moraines formed in a closed system are much older than those built in the absence of a barrier. Also, the compilation implies multiple phases of pre-LGM ice flow that corresponded to global cold periods. We suggest that there was likely a response of blue-ice evolution to Antarctic glaciations on orbital timescales.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"480 ","pages":"Article 109749"},"PeriodicalIF":3.1,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800451","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}