Geomorphology最新文献

{"title":"Ice-flow adjustments during the transition from land- to lake-terminating status of Jiagai Glacier, Eastern Himalaya","authors":"Yunyi Luo ,&nbsp;Qiao Liu ,&nbsp;Xueyuan Lu ,&nbsp;Yongsheng Yin ,&nbsp;Jiawei Yang ,&nbsp;Bo Zhang ,&nbsp;Xuyang Lu","doi":"10.1016/j.geomorph.2025.110044","DOIUrl":"10.1016/j.geomorph.2025.110044","url":null,"abstract":"<div><div>Although most lake-terminating glaciers in the Himalayas exhibit accelerated retreat and thinning, their dynamic response during the transition from land- to lake-terminating conditions remains poorly understood. In this study, we selected the Jiagai Glacier, Eastern Himalaya, as a representative case to investigate this transitional process. We reconstructed surface velocity from 2000 to 2023 using satellite image feature-tracking. Significant dynamic adjustments were observed during the formation and expansion of the proglacial lake, which grew by 0.88 ± 0.12 km² between 1990 and 2023. The lowermost 4.6 km of the glacier tongue experienced substantial changes, with four distinct episodes of acceleration initiating in 2007, 2010, 2013, and 2017. After 2017, the strain regime in the lower section of the glacier shifted from compressive to extensional, evidenced by a reversed surface velocity gradient along the central flowline and a sustained decrease in emergence velocity, suggesting a dynamic thinning process. During this period, spatial heterogeneity in surface velocity was pronounced. The terminus acceleration and topographic steepening likely drove a decoupling of velocity fluctuations between the 1–2.5 km and 2.5–4.6 km segments of the glacier tongue, measured from the glacier terminus, suggesting a reorganization of mass transport processes. By capturing the dynamic evolution of Jiagai Glacier during its transition from land- to lake-terminating conditions, this study provides new insights into the heterogeneous responses of glaciers to climate change. As climate change intensifies, an increasing number of glaciers in the Himalayas and other mountain regions are expected to be influenced by the formation of proglacial lakes. Therefore, accounting for their transition from land- to lake-terminating states is essential when analyzing or predicting glacier dynamics at both regional and global scales.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110044"},"PeriodicalIF":3.1,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223448","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":"Comparison study of active landslides in four giant cascade hydropower station reservoir areas on the Jinsha River, China","authors":"Jian Zhou ,&nbsp;Minggao Tang ,&nbsp;Qiaofeng Zhang ,&nbsp;Chaorui Li ,&nbsp;Yishun Jiang","doi":"10.1016/j.geomorph.2025.110033","DOIUrl":"10.1016/j.geomorph.2025.110033","url":null,"abstract":"<div><div>Large reservoir impoundment poses exceptionally severe impacts on slope stability across extended spatial and temporal dimensions, threatening hydropower infrastructure and downstream communities. Although this is a topic of great concern, there are still many disputes in the characteristics, deformation laws and mechanisms of reservoir-induced landslides. Therefore, this paper systematically compares reservoir-induced landslides in the four world-class giant cascade hydropower stations for the first time. The investigation is carried out by integrating remote sensing techniques, Interferometric Synthetic Aperture Radar (InSAR), and geostatistical analysis methods, and examines 283 landslides (198 reservoir-induced) across the four cascade reservoirs along China's Jinsha River, specifically Xiangjiaba (XJB), Xiluodu (XLD), Baihetan (BHT), and Wudongde (WDD). The results showed: (1) The reservoir-induced landslides are dominated by large-scale accumulation landslides. And reservoir-induced landslides have similar spatial distribution characteristics, mainly in low-relief topography and gentle slopes near dams, concentrating in seven zones. (2) There are significant differences in elevation difference, slope, stratigraphic lithology and relationship with tectonics of reservoir-induced landslides. Their development in in the elevation difference and slope characteristics is ranked as XJB &lt; XLD &lt; WDD &lt; BHT. Geological control patterns vary among reservoirs: XJB is dominated by Jurassic sandstone-mudstone interbedded lithology; XLD and BHT are under strong lithology-structure coupling, controlled by Ordovician-Silurian-Cambrian and Ordovician-Silurian-Proterozoic lithological assemblages, respectively; and WDD, influenced by Jurassic-Proterozoic lithology and structures, is characterized by weak tectono-lithological coupling. (3) Reservoir operation mode is the most important factor affecting the deformation time, degree and mechanism of reservoir-induced landslides. The most intense deformation occurs during the first impoundment stage, and greater water-level fluctuations increase the degree of induced deformation. Hydrodynamic pressure-type landslides, the dominant type, develop on arc slip surfaces and decrease with submergence; buoyancy weight loss-type landslides show a “first increasing then decreasing” trend with submergence, concentrating on chair-shaped slip surfaces. This paper defines the similar and different characteristics of landslide induced by reservoirs, records valuable data, and provides a clear object for the prevention and control of reservoir-induced landslides.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110033"},"PeriodicalIF":3.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223447","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":"Are Palmira sand dunes related to Sangay volcano eruptions? New insights derived from sand dunes mapping using sentinel 2 data","authors":"Miguel Torres-Campozano ,&nbsp;Antonella Bermúdez-Zambrano ,&nbsp;Oswaldo Fuentes-Campuzano","doi":"10.1016/j.geomorph.2025.110030","DOIUrl":"10.1016/j.geomorph.2025.110030","url":null,"abstract":"<div><div>Palmira desert, located in the central Andes of Ecuador, constitutes one of the few deserts that present dark sand dunes, mostly of volcanic ashes. The distribution of these sand dunes was mapped through Maximum Likelihood Classification based on spectral bands and indexes derived from Sentinel 2 data. The distribution of these sands showed an E-W pattern between Sangay volcano and Palmira desert, supporting the Palmira sand dunes' provenance from this volcano. This pattern is also evident in the ash plume frequency map derived from Volcanic Ash Advisory Center data where most ash plumes point to west, to the Palmira desert location. Regional wind models indicate this pattern is due to the dominant E-W winds in the region, which transport ashes from Sangay volcano to Palmira desert, and opposing winds from the west prevent these ashes to be transported beyond Palmira desert location. This provenance from Sangay volcano is also supported by the spectral signature similarity between Palmira sand dunes and Sangay volcanic deposits, suggesting ashes of intermediate composition with abundant ferrous minerals.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110030"},"PeriodicalIF":3.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223449","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":"Slope mass movements and debris flow activity in the Geysernaya River valley (Kamchatka, Russia)","authors":"Ekaterina V. Lebedeva ,&nbsp;Elena A. Baldina ,&nbsp;Sergey S. Chernomorets ,&nbsp;Sergey V. Kharchenko ,&nbsp;Alexey V. Kotenkov ,&nbsp;Bashir M. Kuramagomedov ,&nbsp;Andrey A. Medvedev","doi":"10.1016/j.geomorph.2025.110029","DOIUrl":"10.1016/j.geomorph.2025.110029","url":null,"abstract":"<div><div>A detailed analysis of remote sensing data (1964–2024) and field surveys were used to classify and trace the dynamics of exogenous slope processes in the Geysernaya River valley over 60 years. Repeated low-altitude Unmanned Aerial Vehicle (UAV) surveys and comparison of Digital Elevation Models (DEMs) revealed that landslides and/or rock/debris collapses deliver material into channels, where it is pulsationally transported by debris flows. The formation of large debris flows in the Geysernaya River valley is associated with the collapse of significant fragments of its left side and outburst of dammed lakes. Debris flows from the right side of the valley are associated with the release of cold groundwater, heavy precipitation, and periods of snowmelt, while on the left side they may have a non-seasonal character, as they are formed within the thermal fields under conditions of constant heating and gas-hydrothermal manifestations. The study of endogenous process manifestations (areas of thermal anomalies, current uplifts, faults, epicenters of local earthquakes) and areas of exogenous movements (landslides, debris flow (mudflow) basins, fluvial erosion and accumulation) in the valley allowed identify a zone of potential activation of slope and debris flow processes. The zone covers the left side of the Geysernaya River valley, its bottom, and the basin of the Lavoviy Creek. The action of these processes on the left side of the valley is attributed to a combination of endogenous factors, including the crushing of rocks, their transformation into clays due to gas-hydrothermal impact, as well as heating and increased wetting of the slopes. These findings are crucial for understanding the activity of slope and debris flow processes in geothermal regions. They provide valuable insights that can be applied to other volcanic and hydrothermally active regions, such as the Kuril Islands and other parts of the Pacific Ring of Fire.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110029"},"PeriodicalIF":3.1,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223450","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":"Seasonal variations in the thermal diffusivity of the surface rocks and the effect of moisture","authors":"Hongyu Gu ,&nbsp;Weichang Chen ,&nbsp;Li Li ,&nbsp;Mingshen Shao ,&nbsp;Tiancheng Zhao ,&nbsp;Dong Xu ,&nbsp;Yang Wang ,&nbsp;Zhongjian Zhang ,&nbsp;Junjie Zhang ,&nbsp;Guoqing Li","doi":"10.1016/j.geomorph.2025.110028","DOIUrl":"10.1016/j.geomorph.2025.110028","url":null,"abstract":"<div><div>Rock weathering is a fundamental aspect of Earth's evolutionary processes. The surface rock constitutes a critical zone that interacts with solar and water. However, there has been a lack of data to quantify the transient effects of these interactions. In this study, we employ thermal diffusivity (<span><math><mi>α</mi></math></span>) at a macroscopic scale to investigate the transient thermal response mechanisms, utilizing temperature data collected at multiple depths. The results show that the thermal diffusivity values exhibit seasonal variations, with different trends in winter and summer, and the variation amplitudes show differences at different depths. We analyzed and discussed the mechanism and believe that the cause of the seasonal variation of thermal diffusivity is the change of moisture in the surface rocks and the phase change of water-ice. This study helps to deepen the understanding of the weathering process of surface rocks and its correlation with climate change. At the same time, it provides new insights for application fields such as engineering geology and stone conservation that are concerned about the weathering of surface rocks.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110028"},"PeriodicalIF":3.1,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223451","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":"Multi-temporal DEMs used to quantify the geomorphological impact of a late 20th century glacier re-advance at Schwarzberggletscher, Switzerland","authors":"Toby N. Tonkin ,&nbsp;Nicholas G. Midgley ,&nbsp;Simon J. Cook","doi":"10.1016/j.geomorph.2025.110027","DOIUrl":"10.1016/j.geomorph.2025.110027","url":null,"abstract":"<div><div>Sedimentological investigations have advanced understanding of moraine formation at Alpine glaciers; however, few studies use multitemporal elevation datasets to observe landform generation during a period of glacier re-advance. Archive aerial image sets from 1974 to 2010 were processed using a photogrammetric workflow to visualise and quantify geomorphological change at the margin of Schwarzberggletscher, Switzerland. A combined co-alignment and iterative closest point-based approach was adopted to improve the comparative accuracy of the topographic datasets derived from the historical aerial imagery. This enabled the geomorphological impact of a glacier re-advance that occurred between 1974 and the early 1990s to be monitored. In the geospatial data, we recognise: (i) landform development associated with the advancing glacier terminus between 1974 and 1990; (ii) moraine erosion at the advancing, but fluctuating glacier margin; and (iii) the ablation of buried ice in the proglacial area between 1999 and 2010. The implications of this re-advance on the geomorphological record of glacier change are discussed, with this study providing a median and maximum error thresholded rate of surface lowering for ice-cored moraines of ∼0.2 ma⁻¹ and ∼0.4 ma⁻¹, respectively. Finally, this study highlights the potential of now-readily accessible datasets, and refined image processing workflows involving image co-alignment and fine registration, for aiding future geomorphological research in the Swiss Alps.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110027"},"PeriodicalIF":3.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145134834","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":"Tsunami simulation and boulder transport across contrasting coastal geomorphologies in Sanriku, Japan","authors":"Storm Roberts ,&nbsp;Daisuke Sugawara ,&nbsp;Hidetoshi Masuda ,&nbsp;Sarah J. Boulton","doi":"10.1016/j.geomorph.2025.110026","DOIUrl":"10.1016/j.geomorph.2025.110026","url":null,"abstract":"<div><div>Tsunami boulders serve as crucial indicators for reconstructing past tsunami events, yet their full transport process remains poorly understood. This study investigates tsunami boulder transport at two geomorphically distinct field sites in Japan affected by the 2011 tsunami, integrating field data with a validated tsunami simulation to track wave parameters at every transport stage. The simulation was validated against eyewitness accounts, local reports, and offshore GPS buoy data. Near the shoreline at the Settai site simulated flow velocities reached a maximum of 7.55 m/s, compared to 6.51 m/s at Hoshiyama beach. Inland at Settai, a maximum 15.56 m/s flow velocity and 17.49 m flow depth were recorded just inland of the partially destroyed barrier. Boulder transport information was compiled from previous studies alongside new field data to assess how tsunamis interact with coastal boulder deposits in different geomorphological settings. Comparison of boulder lithologies, shapes, and distributions revealed similarities in wave influence but differences in deposition patterns due to variations in slope. Commonly used initiation of motion equations were then tested against simulated data. For example, Boulder #1 at Hoshiyama beach had an A-axis of 7.35 m and a minimum calculated velocity for initiation of motion of 6.46 m/s, whilst the tsunami simulation estimated a maximum flow velocity of 6.51 m/s. Although these values are similar, the boulder's position on top of other large clasts suggests that greater energy would have been required for transport and emplacement. Overall, the comparisons showed that while recent refinements have significantly improved the accuracy of the equations, they may still overestimate the minimum flow velocity required for boulder transport. By combining detailed field observations with numerical modelling, this study provides a rare case study capturing parameters at all boulder transport stages, offering a critical reference for future tsunami boulder research and model development.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"490 ","pages":"Article 110026"},"PeriodicalIF":3.1,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109879","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":"Coupled control of tectonic and surface processes on the inception and evolution of the East Saharan Mega-depressions","authors":"Abdullah T. Mohammad ,&nbsp;Mohamed Sultan ,&nbsp;Abotalib Z. Abotalib ,&nbsp;Peter Voice ,&nbsp;Hassan Saleh ,&nbsp;Hadi Karimi ,&nbsp;Mustafa Kemal Emil ,&nbsp;Hesham Elhaddad","doi":"10.1016/j.geomorph.2025.110025","DOIUrl":"10.1016/j.geomorph.2025.110025","url":null,"abstract":"<div><div>We present a novel model for the formation and spatial and temporal evolution of topographic mega-depressions in the hyperarid Sahara Desert. The model is based on field observations, structural analysis, remote sensing data, and isotopic measurements of travertine deposits from the eastern Farafra Plateau in the Western Desert, Egypt. Four stages were identified: an initial stage coeval with the Cenozoic rifting in northeast Africa and three stages in the Pleistocene: (a) formation of depressions along fault zones as pull-apart basins and en échelon grabens within transtensional systems; (b) preferential growth of incipient depressions along faults due to groundwater sapping processes; (c) coalescence of depressions to form larger ones through degradation of escarpments and formation of intra-depression landforms; and (d) formation of deep mega-depressions through horizontal and vertical propagation of smaller depressions along the dominant structural grain. The growth of the mega-depressions was accompanied by the development of Theater-Headed Valleys along the escarpments of coalesced depressions, possibly due to groundwater-sapping processes. The proposed model is supported by the isotopic compositions of travertine in the depressions (δ¹⁸O_VSMOW = +17.9 to +19.7 ‰), consistent with deposition from depleted Nubian Sandstone groundwater (δ¹⁸O_VSMOW = −8.0 to −12.8 ‰). Findings include: (1) mega-depressions originate from numerous small, actively growing depressions coalescing into larger structures rather than a single depression retreating over time, (2) geological structures play a pivotal role in the genesis of nascent depressions through the localization and amplification of surface processes. The findings could enhance our understanding of the rates and temporal dynamics of depression formation elsewhere.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"491 ","pages":"Article 110025"},"PeriodicalIF":3.1,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159999","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":"The long transition from deltaic tidal flats to flood plains in the Pearl River delta","authors":"Haixian Xiong ,&nbsp;Yongqiang Zong ,&nbsp;Shuqing Fu ,&nbsp;Lu Min ,&nbsp;Guangqing Huang","doi":"10.1016/j.geomorph.2025.110024","DOIUrl":"10.1016/j.geomorph.2025.110024","url":null,"abstract":"<div><div>To understand how coastal wetlands have evolved from mudflat emergence, vegetation colonization and floodplain formation in relation to the lowering sea level, deltaic progradation, decreasing water salinity and strengthening fluvial process during the late Holocene, this study analyzed five sediment cores from the head area of the Pearl River delta, southern China. The records of microfossil (diatom and pollen) assemblages, geochemistry (TOC and δ¹³C) and radiocarbon dating from these cores reveal the evolutionary history from delta front formation to delta plain formation, and particularly the transition from tidal mudflats to floodplains. This evolutionary history suggests that delta plain sedimentation in this area mainly started later than 4000 years ago, in response to the lowering relative sea level. The transition from the onset of tidal wetlands to the formation of deltaic levee-floodplain system has taken a couple of thousands of years due to the low sediment supply from the Pearl River and the persistent tidal force. In addition, the weak tidal saltwater intrusion into the head delta limited mangrove colonization on the mudflats over the past 4000 years. These details provide new insights for future management of coastal wetland resources and ecological restoration.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"490 ","pages":"Article 110024"},"PeriodicalIF":3.1,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097668","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":"The geomorphological landscape of the Mariuá Archipelago: An anabranching megacomplex system in the Negro River, Amazon Basin (Brazil)","authors":"Matheus Silveira de Queiroz ,&nbsp;Rogério Ribeiro Marinho ,&nbsp;José Alberto Lima de Carvalho ,&nbsp;Camila Fuziel Silva","doi":"10.1016/j.geomorph.2025.110023","DOIUrl":"10.1016/j.geomorph.2025.110023","url":null,"abstract":"<div><div>The Negro River, the Amazon's principal left-bank tributary, exhibits a complex fluvial system of significant ecological and hydrogeomorphological importance. Its middle and lower reaches feature distinctive geomorphological landscapes, notably the Mariuá and Anavilhanas archipelagos, which serve as exemplary sites for investigating large anabranching rivers. This study examines the geomorphology of the Mariuá Archipelago through analysis of water dynamics, fluvial units, and sedimentary characteristics. We evaluated seasonal water level variations, erosion-transport-deposition processes, and grain-size distributions of islands and floodplains, complemented by comprehensive mapping of river units. Volumetric analysis reveals the fundamentally incomplete nature of the Mariuá floodplain, with the degree of incompleteness varying spatially from 30 % in upstream reaches to 60 % downstream, reflecting both temporal progression of filling and interruption of sediment input. The archipelago exemplifies an inherited fluvial landscape in permanent non-equilibrium, maintained by the Negro River's low suspended sediment concentration (3.2 × 10⁶ ton.year⁻¹) and limited stream power. Islands and floodplains comprise predominantly fine sediments (silt, clay, and very fine sand) stabilized by dense vegetation, while sandbars consist of medium to fine sand with occasional granule deposits. Although floodplains function as sediment traps through their levee-depression morphology, current sediment supply cannot explain the archipelago's formation. We propose that the Mariuá Archipelago originated from Japurá River sediments deposited when paleochannels connected these basins, with sediment supply ceasing abruptly around 1000 BP. While this inherited landscape has remained morphologically stable for centuries, recent analysis (2014–2024) reveals a 33 % increase in erosion and 83 % increase in deposition, suggesting the system may be approaching a stability threshold. Climate change and intensifying extreme hydrological events pose significant risks to this delicate equilibrium, potentially triggering irreversible morphological transformations in this unique Amazonian landscape.</div></div>","PeriodicalId":55115,"journal":{"name":"Geomorphology","volume":"490 ","pages":"Article 110023"},"PeriodicalIF":3.1,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097670","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}