Geomorphology最新文献_第6页

Using paired Schmidt Hammer and terrestrial cosmogenic surface exposure dating to study the timing and style of rockfalls in the Rough River Basin, Kentucky: Results, constraints, and possible mechanisms 使用配对的施密特·哈默和地球宇宙表面暴露年代法研究肯塔基州Rough河流域岩崩的时间和风格：结果、限制和可能的机制

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-07 DOI: 10.1016/j.geomorph.2025.110118

Daria Khashchevskaya , Jason M. Dortch , Lewis A. Owen , Paula Figueiredo

The setting of weak shales underlying heavily fractured sandstone caprock, coupled with the wet environmental conditions along the valley slopes of the Rough River Basin in north-central Kentucky, has led to massive rockfalls composed of clusters of sandstone boulders. However, the exact mechanisms of cliff retreat and sediment accumulation due to mass movement in that region remained unclear. In addition, the frequency and timing of these mass movement events are uncertain. To better understand mass movement mechanisms, we used the Schmidt Hammer exposure dating (SHED) technique and terrestrial cosmogenic nuclide dating on two sites in the Rough River basin, “Home Tucker” and “Linda Paul.” The results suggest that the degradation mechanism of sandstone cliffs by mass movement varies due to local geology and climate change. The Home Tucker site exhibits boulder accumulation through rockfall during the Early Holocene (10.6 ± 1.0 to 43.9 ± 3.0 ka), precluding the estimation of a cliff retreat rate. In contrast, the Linda Paul site exhibits block sliding and toppling, with detachment events spanning from 21 ± 1.6 to 66.8 ± 5.4 ka, and an estimated cliff retreat rate of 0.17 ± 0.09 mm/yr for Home Tucker site and 0.22 ± 0.1 mm/yr for the Linda Paul site. These findings suggest that detachment events occurred more frequently during the last glacial maximum, likely due to freeze-thaw processes or rapid climate change. With only one boulder dated to the Holocene, warming and a relatively stable climate during the Holocene have likely slowed cliff degradation. Attempts to develop a reliable SHED calibration curve were hindered by no correlation (r² = 0.1) between ¹⁰Be age and SHED rebound measurement. This lack of correlation is likely due to variable vegetation cover, moisture inconsistencies, temporally non-linear and spatially heterogeneous weathering of quartz arenite, inheritance of weathering from before rock fall, and bed-dependent variations in strength.

在肯塔基州中北部的Rough River流域，脆弱的页岩位于严重断裂的砂岩盖层之下，再加上河谷斜坡的潮湿环境，导致了由砂岩巨石群组成的大规模落石。然而，由于该地区的质量运动，悬崖退缩和沉积物堆积的确切机制尚不清楚。此外，这些大规模运动事件的频率和时间是不确定的。为了更好地理解质量运动机制，我们在Rough河流域的“Home Tucker”和“Linda Paul”两个地点使用了Schmidt Hammer暴露测年（SHED）技术和陆地宇宙形成核素测年。结果表明，砂岩崖体运动的退化机制因局部地质和气候变化而异。Home Tucker遗址显示，在全新世早期（10.6±1.0至43.9±3.0 ka），岩石通过落石堆积，排除了悬崖退缩率的估计。相比之下，Linda Paul遗址表现出块体滑动和倾倒，分离事件跨度为21±1.6至66.8±5.4 ka，估计Home Tucker遗址的悬崖后退率为0.17±0.09 mm/年，Linda Paul遗址为0.22±0.1 mm/年。这些发现表明，拆离事件在末次盛冰期发生的频率更高，可能是由于冻融过程或快速的气候变化。只有一块巨石可以追溯到全新世，全新世期间的变暖和相对稳定的气候可能减缓了悬崖的退化。由于10Be年龄与SHED回弹测量值之间没有相关性（r2 = 0.1），建立可靠的SHED校准曲线的尝试受到阻碍。这种相关性的缺乏可能是由于不同的植被覆盖、水分不一致、石英砂岩的时间非线性和空间非均质风化、岩石坠落前的风化继承以及强度的层依赖性变化。

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引用次数: 0

Rock glacier velocity monitored by annual in-situ geodetic surveys: Long-term challenges, solutions and suggestions 岩石冰川速度监测的年度原位大地测量：长期挑战，解决方案和建议

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-05 DOI: 10.1016/j.geomorph.2025.110117

Andreas Kellerer-Pirklbauer , Xavier Bodin , Reynald Delaloye , Christophe Lambiel , Isabelle Gärtner-Roer , Bodo Damm , Atsushi Ikeda , Viktor Kaufmann , Karl Krainer , Roberto Seppi , Cristian Scapozza , Martin Stocker-Waldhuber , Emmanuel Thibert

We provide an overview of geodetic survey designs conducted on 43 rock glaciers (RG) in the European Alps, embed these in an overview of the pioneering phase of monitoring RG movement, and compare our approaches with other studies. Different in-situ geodetic approaches used for the annual survey of RG velocity (RGV) and RG frontal advance (RGA) are examined. Geodetic-based RGV monitoring in the Alps started in 1918 and RGA in 1921. RGV is an associated parameter of the Essential Climate Variable “Permafrost” since 2022. Nowadays, satellite-based positioning or classic measurements with a total station are used for in-situ geodetic surveys. The total number of surveyed boulders at the 43 RGs varies from 1 to 206. In most cases, only a part of these points is considered as “reference points” used to calculate the RGV value of RG units. The density of reference points for RGV calculation ranges from 27.5 to 1143 pts./km². For RGV monitoring using annual geodetic surveys, we suggest: (a) selecting a RG where multi-decennial monitoring seems to be feasible, (b) distributing uniformly observation points over the entire RG unit of interest along either profiles or well-distributed boulders, (c) repeating measurements always at the same time of the year (September), (d) site-RGV-averaging using all data points, (e) site-RGV-averaging using only the survey markers considered to be the most suitable for long-term monitoring, (f) providing additional statistical information of these points and in particular of the central flowline, and (g) securing long-term storage of original data, metadata and results.

我们概述了在欧洲阿尔卑斯山的43个岩石冰川（RG）上进行的大地测量设计，将这些设计嵌入到监测RG运动的先驱阶段的概述中，并将我们的方法与其他研究进行了比较。研究了不同的大地测量方法在RG速度（RGV）和RG锋面推进（RGA）年度测量中的应用。阿尔卑斯山基于大地测量学的RGV监测始于1918年，RGA始于1921年。RGV是2022年以来基本气候变量“永久冻土”的相关参数。目前，原位大地测量主要采用卫星定位或全站仪的经典测量方法。在43个地质勘探区所调查的巨石总数由1个至206个不等。在大多数情况下，这些点中只有一部分被视为“参考点”，用于计算RG单位的RGV值。RGV计算参考点密度为27.5 ~ 1143 pts./km2。对于利用每年的大地测量监测地表生物，我们建议：(a)选择一个似乎可以进行多年监测的RG， (b)沿着剖面或分布均匀的巨石在整个感兴趣的RG单元上均匀分布观测点，(c)总是在一年的同一时间（9月）重复测量，(d)使用所有数据点进行场址- rgv平均，(e)仅使用被认为最适合长期监测的调查标记进行场址- rgv平均，(f)提供这些点，特别是中央管线的额外统计信息；(g)确保原始数据、元数据和结果的长期存储。

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引用次数: 0

Mechanisms of landslides induced by extreme rainfall in folded mountains: Case study of Zhenba, July 1, 2023 极端降雨对褶皱山滑坡的影响机制——以镇坝为例，2023年7月1日

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-05 DOI: 10.1016/j.geomorph.2025.110115

Wenbo Zheng , Wen Fan , Yanbo Cao , Xin Liang , Shaoqing Yuan , Nuanzong Zhang , Shilin Zhang , Pengxu Jing

Regional record-breaking heavy rainfall can significantly exacerbate landslide disasters and pose severe threats to structurally complex mountainous areas that are vulnerable to external environmental variations. To better understand the effects of extreme rainfall on geological structures in folded mountains, a recent event in July 2023 in Zhenba County, Qinling-Daba Mountains area, Shaanxi Province, China, is investigated using observations and reanalysis data. Remote sensing interpretation of satellite imagery identified significant surface changes before and after the rainfall. Field investigations further characterized the distribution, size, and mobility of landslides. A comprehensive disaster database, comprising 719 landslides and 293 debris flows, was compiled to examine the geological and topographical factors driving widespread failures. Numerical simulations were conducted to assess the effects of rainfall infiltration on pore water pressure and slope stability. The results revealed a strong correlation between high-mobility landslides and short-duration, high-intensity rainfall events. Debris flow-induced toe erosion significantly contributed to the initiation of additional landslides. Rock landslides, which accounted for 58.8 % of total geological disasters, were widespread across the region. Geological disasters developed most abundantly in rock layers conforming to bedding planes, accounting for 52 % of all recorded events. The highest disaster density was 3.81 events km⁻² in the core strata of anticlines. Additionally, near-horizontal rock layers in syncline cores present a potential risk for deep-seated landslides. The study area is experiencing an unprecedented climatic shift. The research provides a scientific foundation for predicting and issuing early warnings for regional geological disasters, as well as for disaster prevention and mitigation.

区域性破纪录强降雨可显著加剧滑坡灾害，对易受外部环境变化影响的结构复杂山区构成严重威胁。为了更好地了解极端降雨对褶皱山地质构造的影响，利用观测和再分析资料，对2023年7月发生在陕西省秦巴山区镇巴县的一次极端降雨事件进行了研究。卫星图像的遥感解译确定了降雨前后显著的地表变化。实地调查进一步描述了滑坡的分布、规模和流动性。我们编制了一个全面的灾害数据库，包括719宗山体滑坡和293宗泥石流，以研究导致大范围滑坡的地质和地形因素。通过数值模拟研究了降雨入渗对孔隙水压力和边坡稳定性的影响。结果表明，高流动性滑坡与短时间、高强度降雨事件之间存在很强的相关性。泥石流引起的坡脚侵蚀是引发额外滑坡的重要因素。岩石滑坡分布广泛，占总地质灾害的58.8%。地质灾害在符合层理平面的岩层中最为丰富，占所有记录事件的52%。背斜核心层的灾害密度最高，为3.81次km−2。此外，向斜岩心中的近水平岩层存在深层滑坡的潜在风险。研究区域正经历着前所未有的气候变化。该研究为区域地质灾害的预测预警和防灾减灾提供了科学依据。

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引用次数: 0

Surface processes in the Horqin Sandy Land, northeastern China: Insights from grain size and shape of sediments 中国东北科尔沁沙地表层过程：来自沉积物粒度和形状的启示

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-05 DOI: 10.1016/j.geomorph.2025.110116

Deyang Zhang, Hongwei Li, Xiaoping Yang, Xinchen Yu , Steve Pratte, Bo Chen

Fluvial-aeolian interactions are integral to the evolution of desert landscapes, yet the associated processes and sediment sources remain an area of active investigation. Recent studies highlight the potential of grain shape characteristics as indicators of sediment transport history and provenance. The Horqin Sandy Land (HQ) in northeastern China is a dunefield characterized by intensive fluvial-aeolian interactions. However, surface processes and its provenance connection with the upwind Hunshandake Sandy Land (HSDK) require further clarification.

The grain size and shape of fluvial sediments and dune sand samples from the HQ and surrounding regions were analyzed to elucidate transport processes and sand provenance. The grain shape of most river sediments significantly differs from that of aeolian sands in the HQ, except for sediments from the Xilamulun River (XLML), which originate in the HSDK and exhibit grain shape characteristics similar to HQ aeolian sands. Approximately 80 % of the fine sand transported by the XLML is derived from the HSDK, resulting in high sphericity of finer sand in the western HQ. Aeolian sands in the HQ exhibit pronounced spatial heterogeneity in grain size and shape parameters, reflecting strong fluvial-aeolian interactions. Wind-driven sorting and abrasion exert dominant control on sediment patterns in the western and central HQ, while their impacts are diminished in the eastern HQ due to a barrier effect of rivers and increased sediments influx from the Yanshan Mountains.

These findings highlight the complexity of fluvial-aeolian sediment dynamics. Moreover, they demonstrate that grain-shape analysis—characterized by low cost and high efficiency—can effectively resolve sediment provenance and surface processes even when their geochemical signatures are similar, underscoring its unique value as a tracer in desert environments.

河流-风沙相互作用是沙漠景观演变的组成部分，但相关的过程和沉积物来源仍然是一个积极研究的领域。最近的研究强调了颗粒形状特征作为沉积物输运历史和物源指标的潜力。中国东北部科尔沁沙地是一个以强烈的河流-风沙相互作用为特征的沙丘地带。然而，地表过程及其与逆风浑善达克沙地（HSDK）的物源关系有待进一步澄清。分析了青海及周边地区河流沉积物和沙丘砂样品的粒度和形状，以阐明泥沙的搬运过程和物源。除西拉穆伦河（XLML）沉积物起源于HSDK，其颗粒形状特征与HQ风沙相似外，大多数河流沉积物的颗粒形状与HQ风沙有显著差异。xml输送的细砂约有80%来自HSDK，导致西部总部的细砂球度高。高原风沙在粒度和形状参数上表现出明显的空间异质性，反映出强烈的河流-风沙相互作用。在西部和中部HQ，风力分选和磨蚀对沉积物形态的影响占主导地位，而在东部HQ，由于河流的屏障作用和燕山沉积物流入的增加，其影响减弱。这些发现突出了河流-风成沉积动力学的复杂性。此外，他们还证明，即使地球化学特征相似，颗粒形状分析也能有效地解决沉积物来源和地表过程，这凸显了它作为沙漠环境示踪剂的独特价值，其特点是成本低、效率高。

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引用次数: 0

A conceptual model of bed deformation and bank erosion in the bifurcated reaches of the Middle Yangtze River 长江中游分岔河段河床变形与河岸侵蚀的概念模型

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-03 DOI: 10.1016/j.geomorph.2025.110114

Heng Zhu , Junqiang Xia , Shanshan Deng , Meirong Zhou

The evolution of bifurcated reaches is complicated owing to flow and sediment diversion at bifurcation and subsequent differential branch deformation. Previous numerical studies have mostly focused on short-term bed deformation in bifurcated reaches, overlooking the process of bank erosion, and their practical application is often limited by high computational costs and the necessity for high-precision topographic data. Therefore, a conceptual model was proposed to simultaneously simulate bank erosion and bed deformation processes of different branches, calibrated and verified using the measurements from two typical bifurcated reaches in the Middle Yangtze River. Results show that: (i) the main branch experienced scouring, while the secondary branch showed deposition or slight scouring, with the calculated cross-sectional profiles closely matching the measurements; (ii) the mid-channel bar adjacent to the main branch exhibited more intense bank erosion due to a higher flow diversion ratio, with a bank retreat width of about 10 m, further promoting the development of the main branch; and (iii) the fluvial erosion intensity of incoming flow-sediment conditions showed a positive correlation with the deformation difference between the branches, and short branches with small bifurcation angles experienced stronger erosion compared with long branches. Besides, engineering interventions that rose the riverbed elevation at the main branch entrance by 1 m could switch the roles of the main and secondary branches, potentially promoting the transition from a two-branched system to a single-channel system.

由于分叉处水流泥沙的分流和随后的差异分支变形，分叉河段的演化十分复杂。以往的数值研究大多集中在分岔河段的短期河床变形，忽略了河岸侵蚀过程，其实际应用往往受到计算成本高和需要高精度地形数据的限制。为此，提出了一个同时模拟不同支流侵蚀和河床变形过程的概念模型，并利用长江中游两个典型分叉河段的实测数据进行了标定和验证。结果表明：(1)主支流发生冲刷，次支流发生淤积或轻微冲刷，计算断面与实测结果吻合较好；(2)靠近主支流的中沙坝由于导流比较大，冲岸较为强烈，退岸宽度约为10 m，进一步促进了主支流的发育；(3)来水流沙条件的河流侵蚀强度与支流间的变形差呈正相关，分叉角小的短支流比长支流受侵蚀更强。此外，将主支流入口处的河床标高提高1米的工程干预措施可以转换主支流和次级支流的角色，从而有可能促进从双支流系统向单通道系统的转变。

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引用次数: 0

Hydromorphological adjustment and river–lake disconnection in the Jingjiang Reach under long-term regulation of three Gorges Reservoir 三峡库区长期调蓄下荆江河段水文形态调整与河湖断流

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-03 DOI: 10.1016/j.geomorph.2025.110113

Wenguang Luo , Yancheng Han , Liming Yan , Jun Xia , Guoqiang Tang

Large dam operations can profoundly reshape downstream river morphology and disrupt river–lake interactions, leading to significant hydrological and ecological consequences. This study investigates long-term hydromorphological changes in the Jingjiang Reach of the Yangtze River following the operation of the Three Gorges Reservoir (TGR) since 2003. Based on daily discharge and water level data from three key hydrological stations (Zhicheng, Shashi, and Jianli), power-law stage–discharge relationships were developed to characterize channel evolution. Effective base level analysis indicated negligible change at Zhicheng but substantial riverbed incision at Shashi and Jianli, with mean lowering rates of 0.271 and 0.256 m/year, respectively. By 2024, cumulative channel storage had increased by approximately 2.45 billion m³, equivalent to 11 % of the average volume of Dongting Lake. Under the original hydrological regime, the Yangtze River flow was distributed into Dongting Lake through three main distributary inlets—Songzikou, Taipingkou, and Ouchikou. Results show a marked decline after TGR impoundment, particularly at Taipingkou and Ouchikou, where linear trends suggest potential inflow cessation by the mid-21st century. Extrapolated trends indicate that channel storage may reach 7.4 billion m³ by 2071, coinciding with a transition toward a “one-in, three-out” regime. This evolving hydrodynamic pattern is expected to weaken Dongting Lake's flood regulation capacity and exacerbate hydrological and ecological fragmentation. These findings highlight the necessity of integrated morphological monitoring and adaptive water management to mitigate the cumulative impacts of large-scale reservoir regulation on downstream river–lake systems.

大型水坝的运行可以深刻地改变下游河流的形态，破坏河湖相互作用，导致重大的水文和生态后果。本文研究了2003年三峡水库运行以来长江靖江河段的长期水文形态变化。基于三个关键水文站（智城、沙市和建利）的日流量和水位数据，建立了幂律级流量关系来表征河道演变。有效基准面分析表明，芷城的变化可以忽略不计，而沙市和建利的河床切口变化较大，平均下降率分别为0.271和0.256 m/年。到2024年，洞庭湖累计蓄水量增加约24.5亿m3，相当于洞庭湖平均蓄水量的11%。在原有水文条件下，长江水流主要通过松子口、太平口、瓯池口三个主要分流口进入洞庭湖。结果表明，三峡水库蓄水后，三峡库区径流明显减少，尤其是太平口和瓯池口，其线性趋势表明，三峡库区在21世纪中期可能停止径流。外推的趋势表明，到2071年，渠道储存量可能达到74亿立方米，与向“一进三出”制度的过渡相吻合。这种不断演变的水动力格局将削弱洞庭湖的防洪能力，加剧水文和生态破碎化。这些发现强调了综合形态监测和适应性水管理的必要性，以减轻大规模水库调节对下游河流-湖泊系统的累积影响。

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引用次数: 0

Morphometric typology of closed depressions in the loess belt and its link to land cover (Nałęczów Plateau, East Poland) 黄土带封闭洼地的形态类型及其与土地覆被的关系（Nałęczów高原，东波兰）

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-02 DOI: 10.1016/j.geomorph.2025.110103

Leszek Gawrysiak , Waldemar Kociuba

The relief of loess areas is undergoing continuous change. Among its features are closed depressions (CDs), which diversify the monotonous surface of the loess plateau. These are landforms that have formed and developed since the end of the last glacial, when the accumulation of loess was completed. These forms are common in all loess areas of the world. Their origin is linked to the morphology of the initial loess plain and natural processes, as well as human activity. Previous studies of their morphology and morphometric features have been based on field studies and analysis of topographic maps. With the availability of high-resolution Digital Terrain Models derived from Light Detection and Ranging (LiDAR) survey, the possibility of conducting much more accurate analyses of the distribution and morphometric features of closed depressions has become available. The Nałęczów Plateau (493 km²), a region located in eastern Poland and almost entirely covered by loess, was selected for a detailed study of CD landforms. Using dedicated algorithms, implemented in a Geographic Information System (GIS), 5320 CDs were extracted from DTM's of 1x1m resolution, and their basic morphometric features were calculated. CDs vary in shape and size, and their area reaches up to 36,625m². On the basis of the database prepared in this way, clustering was carried out and three main landform types (groups), characterized by unique features, were identified. First type, most frequent, are smallest, oval CDs which represent the last stage of evolution (disappearance), second, medium size type occur less frequent and third, largest size and complex shape is least numerous. Both, second and third, represent intermediate stage of development. In the next step, the variability of morphometric features was analysed in relation to the main land cover types. It was found that the groups differed significantly in their morphometric features according to land cover.

黄土区地形正经历着不断的变化。其特征之一是封闭的洼地，使黄土高原单调的地表变得多样化。这些地貌是在末次冰期结束后形成和发展起来的，当时黄土的堆积已经完成。这些形式在世界上所有的黄土地区都很常见。它们的起源与原始黄土平原的形态、自然过程以及人类活动有关。以往对其形态和形态特征的研究都是基于野外考察和地形图分析。随着来自光探测和测距（LiDAR）调查的高分辨率数字地形模型的可用性，对封闭凹陷的分布和形态特征进行更准确的分析成为可能。Nałęczów高原（493平方公里）位于波兰东部，几乎完全被黄土覆盖，被选中进行CD地形的详细研究。利用地理信息系统（GIS）实现的专用算法，从1x1m分辨率的DTM图像中提取5320张cd，并计算其基本形态特征。cd的形状和大小各不相同，其面积可达36625平方米。在此基础上进行聚类，确定了3个主要的地貌类型（群），各具特色。第一种类型是最常见的，是最小的，椭圆形的cd，代表了进化的最后阶段（消失），第二种，中等大小的类型出现的频率较低，第三种，最大的尺寸和复杂的形状最少。第二阶段和第三阶段都是发展的中间阶段。在接下来的步骤中，分析了与主要土地覆盖类型相关的形态特征变异。研究发现，不同土地覆盖条件下，各类群的形态特征存在显著差异。

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引用次数: 0

Climate controls denudation rates from earthquake-triggered landslides in tectonically active mountains 在构造活跃的山区，气候控制着地震引发的滑坡的剥蚀率

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-11-30 DOI: 10.1016/j.geomorph.2025.110112

Mengjie Yang , Shenghua Cui , Xiangjun Pei , Tao Jiang

Against the backdrop of global climate change, the combined effects of frequent seismic activity, intense rainfall, and steep terrain have heightened landslide risks in the Himalayan region. Existing regional-scale studies have primarily focused on landslide denudation triggered by either rainfall or earthquakes, while investigations considering their combined influence remain limited. This study quantifies landslide denudation caused by the Wenchuan earthquake. It examines its relationship with the coupling of rainfall and seismic activity, thereby assessing the impact of rainfall–earthquake interactions on topographic evolution. Based on an analysis of landslide spatial distribution data, topographic indicators, rainfall, and earthquake parameters. We identified a significant nonlinear relationship between landslide denudation rates and topographic metrics. The coupling of rainfall and earthquakes substantially amplified landslide denudation rates. Rainfall continuously weakened rock mass strength through cyclical weathering and fluctuations in pore water pressure; when seismic events occurred, the equivalent rock strength further declined and surpassed the critical threshold for slope failure. This process increased landslide denudation rates and reduced the degree of nonlinearity, with the reduction being most pronounced under hard-rock conditions. Overall, this study enhances the understanding of erosion dynamics driven by extreme events in active orogenic belts.

在全球气候变化的背景下，频繁的地震活动、强降雨和陡峭地形的综合影响加剧了喜马拉雅地区山体滑坡的风险。现有的区域尺度研究主要集中在降雨或地震引发的滑坡剥蚀上，而考虑到两者综合影响的调查仍然有限。本研究量化了汶川地震引起的滑坡剥蚀。它考察了它与降雨和地震活动耦合的关系，从而评估降雨-地震相互作用对地形演变的影响。基于对滑坡空间分布数据、地形指标、降雨和地震参数的分析。我们确定了滑坡剥蚀率与地形指标之间存在显著的非线性关系。降雨和地震的耦合大大增加了滑坡的剥蚀率。降雨通过循环风化和孔隙水压力的波动不断削弱岩体强度；当地震事件发生时，等效岩石强度进一步下降，超过边坡破坏的临界阈值。这一过程增加了滑坡剥蚀率，降低了非线性程度，在硬岩条件下这种降低最为明显。总的来说，本研究增强了对活动造山带极端事件驱动的侵蚀动力学的认识。

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引用次数: 0

A new Multiple Flow Direction (MFD) algorithm for modeling ridge and valley evolution 一种新的多流向（MFD）算法，用于模拟脊谷演化

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-11-29 DOI: 10.1016/j.geomorph.2025.110111

Hiroshi Serizawa, Takashi Amemiya, Kiminori Itoh

Channelized ridge and valley evolution in the Landscape Evolution Model (LEM) is strongly affected by flow direction algorithms. In particular, the Multiple Flow Direction (MFD) is believed to be indispensable for development of tree-shaped river channel networks. An original MFD system is presented in this research and compared with several already known MFD systems. In our new MFD system, all the segments of flow lines with a unit length are consecutively connected one after another. In addition, two or three new flow lines start from the adjacent cells around each node. Thus, the mechanism of our MFD system is considered to be the creation of new headwaters, where the key indicator is the distance between the node and the central points of surrounding cells. In our numerical simulations, tectonic uplift is regarded as compensation of the soil, which is carried out separately from erosion and diffusion processes expressed by the partial differential equation. As a result, the altitudes of topography are entirely included within a range of 0 ≤ z ≤ 1 all the time. In addition, we propose a new mechanism called the altitude effect that adjusts the mountain profile, which is mainly applied to existing MFD systems such as the D∞ model and the TOPMODEL. Free-pass boundary conditions are imposed that guarantee free and immediate discharge of the soil and water through four boundaries.

在景观演化模型（LEM）中，河道化脊谷演化受水流方向算法的强烈影响。特别是多流向（MFD）被认为是树形河道网发展的必要条件。本研究提出了一种原始的MFD系统，并与几种已知的MFD系统进行了比较。在我们的新型MFD系统中，单位长度的所有流线段都是连续连接的。此外，两个或三个新的流线从每个节点周围的相邻单元开始。因此，我们的MFD系统的机制被认为是新的源头的产生，其中关键指标是节点与周围细胞中心点之间的距离。在我们的数值模拟中，构造隆升被认为是对土壤的补偿，它与用偏微分方程表示的侵蚀和扩散过程分开进行。因此，地形高度始终完全包含在0≤z≤1的范围内。此外，我们还提出了一种新的机制，称为海拔高度效应，该机制主要应用于现有的MFD系统，如D∞模型和TOPMODEL。实行自由通行边界条件，保证土壤和水通过四个边界自由和立即排放。

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引用次数: 0

Heterogeneity of complex landslides from the perspective of dendrogeomorphology 从树木地貌学角度看复杂滑坡的异质性

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-11-27 DOI: 10.1016/j.geomorph.2025.110108

Karel Šilhán

Complex landslides are characterised by the presence of zones with different depths and mechanisms of movement. From the perspective of dendrogeomorphic research, however, these landslides are generally treated as homogeneous units, which can, however, introduce critical scatter and ambiguity in the results. This limitation is particularly serious because tree-ring based approaches are currently considered the most accurate tool for dating landslides in temperate climates. Thus, this study focused on distinguishing the specificity of landslide movement behaviour in two contrasting zones within a complex landslide area through dendrogeomorphic methods. Three complex landslides were studied using data from 746 increment cores of disturbed trees. Within each area, two different landslide types (zone of earthflow and zone of rotational landslide) were defined and analyzed separately. Dendrogeomorphic analysis revealed major differences between the two zones in several parameters. Trees in the two zones responded differently to the ratio of the two types of growth disturbances. Rotational landslides and earthflows showed different frequencies of occurrence and sizes of reactivated areas. In addition, magnitude-frequency analyses suggested different physical mechanisms for the two processes. The difference in potential triggers was found to be crucial. Earthflows zones responded to short-term precipitation extremes after a long dry period, whereas rotational landslide zones responded to medium-term extremes after several years of above-average precipitation. Thus, the results of the study clearly indicate the necessity of strict separation of the contrast landslide types within complex landslides in dendrogeomorphic research for higher accuracy of results with minimization of their scatter.

复杂滑坡的特点是存在不同深度和运动机制的带。然而，从树木地貌研究的角度来看，这些滑坡通常被视为均匀的单元，这可能会导致结果的临界分散和模糊性。这种限制尤其严重，因为基于树木年轮的方法目前被认为是测定温带气候下山体滑坡年代的最准确工具。因此，本研究的重点是通过树木地貌方法来区分复杂滑坡区内两个不同区域的滑坡运动行为的特殊性。利用746棵扰动树木增量岩心数据，对3个复杂滑坡进行了研究。在每个区域内，分别定义了两种不同的滑坡类型（土流带和旋转滑坡带）并进行了分析。树木地貌分析揭示了两个地区在几个参数上的主要差异。两个区域的树木对两种生长干扰的比例有不同的反应。旋转滑坡和土流显示出不同的发生频率和恢复区域的大小。此外，震级-频率分析表明这两个过程的物理机制不同。潜在诱因的差异被发现是至关重要的。土流带在长期干旱后响应短期极端降水，而旋转滑坡带在几年高于平均水平的降水后响应中期极端降水。因此，研究结果清楚地表明，在树木地貌研究中，必须对复杂滑坡中的对比滑坡类型进行严格的分离，以提高结果的准确性，最大限度地减少它们的分散。

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