Geomorphology最新文献_第2页

Assessing landslide susceptibility and dynamics at cultural heritage sites by integrating machine learning techniques and persistent scatterer interferometry 通过整合机器学习技术和持久散射干涉测量法评估文化遗址的滑坡易发性和动态性

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-20 DOI: 10.1016/j.geomorph.2024.109522

José Eduardo Bonini , Carlotta Parenti , Francesca Grassi , Francesco Mancini , Bianca Carvalho Vieira , Mauro Soldati

Landslides can significantly affect cultural heritage sites worldwide, often leading to irreversible damage and loss of invaluable cultural assets, and the assessment of the spatio-temporal distribution of such processes in culturally relevant sites is still a challenge. In this study, we propose a workflow to assess landslide susceptibility at the catchment scale and landslide dynamics, in terms of state of activity, at the slope scale with reference to built environments. A fully open-source and quantitative approach that integrates machine learning methods and persistent scatterer interferometry is proposed. The workflow was tested to identify cultural heritage sites potentially affected by landslides in a catchment of the Northern Apennines (Italy) characterized by the occurrence of earth slides and earth flows. The research reveals that 18 sites are located in highly susceptible terrains and five of them display notable displacement rates. Two sites in the highest susceptibility class and with high displacements rates were selected as case studies. One of the sites showed displacement rates up to 8 mm/year, while the second one up to 80 mm/year. A seasonal pattern of displacements was observed, with higher rates during summer and autumn. The analysis suggested a remarkable influence of topographic conditioning factors for the identification of earth slide susceptibility, while lithology was more important for the identification of earth flow susceptibility. Limitations due to the widespread occurrence of landslides characterized by a complex style of activity and the yearly update schedule of the interferometric data used are acknowledged. Nonetheless, the proposed workflow demonstrates its replicability with minimal operational costs to assess landslide susceptibility and state of activity in diverse geomorphological contexts.

山体滑坡会严重影响世界各地的文化遗址，往往会导致不可逆转的破坏和宝贵文化资产的损失，而评估此类过程在文化遗址中的时空分布仍是一项挑战。在本研究中，我们提出了一种工作流程，用于评估集水区尺度上的滑坡易发性和斜坡尺度上的滑坡动态，即参照建筑环境的活动状态。我们提出了一种完全开源的定量方法，将机器学习方法和持久散射干涉测量法融为一体。对该工作流程进行了测试，以确定意大利亚平宁山脉北部集水区可能受滑坡影响的文化遗址，该集水区的特点是滑坡和泥石流频发。研究显示，18 处遗址位于极易发生滑坡的地形上，其中 5 处显示出显著的位移率。研究选取了两个易受影响程度最高且位移率较高的地点作为案例研究。其中一个地点的位移率高达 8 毫米/年，第二个地点的位移率高达 80 毫米/年。据观察，位移具有季节性，夏季和秋季位移率较高。分析表明，地形条件因素对确定土崩易发性有显著影响，而岩性对确定土流易发性更为重要。由于山体滑坡的广泛发生，其活动方式复杂，而且所使用的干涉测量数据每年更新一次，因此存在一定的局限性。尽管如此，建议的工作流程证明了其可复制性，以最低的运行成本评估不同地貌背景下的滑坡易发性和活动状态。

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引用次数: 0

Anthropogenic legacy sediment budgets in heavily disturbed historical mining catchments

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-19 DOI: 10.1016/j.geomorph.2024.109518

Mark Kincey , Jeff Warburton

Unregulated metal mining mobilises high volumes of waste sediments to river systems within impacted catchments, increasing sediment yields, contaminating floodplain stores, and profoundly altering long-term patterns of channel planform evolution. However, quantifying the actual scale of historical mine sediment production and dispersal remains a significant challenge, due largely to the variable quality, character and availability of disparate datasets relating to past mining operations. In this study, we reconstruct anthropogenic sediment production associated with historical lead mining between 1700 and 1948 for a globally significant orefield in the North Pennines, UK, that includes the headwater catchments of two major river systems: the River South Tyne and the River Tees. Using a range of interdisciplinary methods including digital terrain analyses and ore-to-waste sediment scaling ratios, we find that mining produced 4.4 × 10⁵ t of lead ore during the study period, but also mobilised an estimated 7.2 × 10⁶ t of associated waste sediment. Approximately 67 % of this waste sediment cannot be accounted for within extant anthropogenic sediment storage landforms within the catchment areas. Surface working using managed water supply (hushing) was the key sediment production process, with 64 % of waste sediment originating from surficial hushing but only 36 % from subterranean mining. The high connectivity of hushes with river channels resulted in minimal (<1 %) long-term sediment storage in the form of hush outwash fans. We find pronounced spatial and temporal variability in legacy sediment production and storage, which has important implications for understanding reach-scale patterns of channel response to historic mining operations.

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引用次数: 0

Frost weathering in contemporary active-layer deposits—micro-scale records from Kaffiøyra Plain (NW Spitsbergen) 当代活动层沉积中的霜冻风化--来自卡菲奥伊拉平原（斯匹次卑尔根西北部）的微尺度记录

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-17 DOI: 10.1016/j.geomorph.2024.109510

Karolina Ulbin , Barbara Woronko , Ireneusz Sobota

Frost weathering serves a critical role under cold, nonglacial (i.e., periglacial) conditions. Within a contemporaneous active layer, the progressive development of microscale frost-weathering features may be recorded on the surface of sand-fraction quartz grains (0.5–0.8 mm). The purpose of this study is to identify the factors responsible for the effects of this type of frost weathering. Sediments from four profiles were tested from the Kaffiøyra Plain (NW Spitsbergen) in 2011. These profiles represent sediments of various origins and ages, ranging from 11 to 9 ka B.P., and on to the Little Ice Age. Scanning electron microscopy, grain-size distribution, CaCO₃ content, pH, and deposit geochemistry were used to determine the intensity of frost weathering on study sediments. The results from sand-sized quartz-grain microtexture analysis indicates that a low degree of micro-scale frost weathering had occurred regardless of sediment age. Most of the micro-scale frost-weathering effects were recorded in the active layer's top and base. Quartz-sand-grain microtextures predominate in these two locations, their extant providing insight into the initial development of such weathering. Microtexture's predominance signifies an inception of weathering development, manifested as large and small conchoidal fractures (>10 μm and <10 μm, respectively). Small and large breakage blocks (>10 μm and <10 μm, respectively) are recorded as accessory microtextures, requiring more freeze–thaw cycles and longer operating times. Of note, frost-weathering effects are dependent on grain-size composition; the finer the sediment, the more intense is the grain-weathering development.

在寒冷的非冰川（即围冰期）条件下，霜冻风化起着至关重要的作用。在同时期的活动层中，沙粒石英颗粒（0.5-0.8 毫米）表面可能会记录到微尺度霜冻风化特征的逐渐发展。本研究的目的是确定造成这种霜冻风化影响的因素。2011 年对卡菲奥伊拉平原（斯匹次卑尔根西北部）四个剖面的沉积物进行了测试。这些剖面代表了不同来源和年龄的沉积物，范围从公元前 11 ka 到 9 ka，直至小冰河时期。扫描电子显微镜、粒度分布、CaCO3 含量、pH 值和沉积物地球化学被用来确定研究沉积物的霜冻风化强度。砂粒大小的石英微纹理分析结果表明，无论沉积物的年龄如何，都发生了较低程度的微尺度霜冻风化。大部分微尺度霜冻风化效应出现在活动层的顶部和底部。石英-砂粒微纹理在这两个位置占主导地位，它们的存在有助于了解此类风化的最初发展。微纹理占主导地位标志着风化发展的开始，表现为大、小锥形裂缝（分别为 10 μm 和 10 μm）。小断裂块和大断裂块（分别为 10 μm 和 10 μm）被记录为附属微质，需要更多的冻融循环和更长的操作时间。值得注意的是，霜冻风化效应取决于粒度组成；沉积物越细，粒度风化的发展就越强烈。

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引用次数: 0

Bypassing at a headland-controlled meso-scale tidal inlet 岬角控制的中尺度潮汐入海口旁路

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-17 DOI: 10.1016/j.geomorph.2024.109512

Mariane Couceiro Pullig , Antonio Henrique da Fontoura Klein , Laís Pool , Deivid Cristian Leal Alves , João Thadeu de Menezes

In this paper, a conceptual model is presented addressing the morphological evolution of a headland-controlled inlet at Babitonga Bay, Southern Brazil. Multiple historic bathymetric datasets were compiled spanning a period of 160 years (1862–2021). A test of various interpolation methods identified the Empirical Bayesian Kriging interpolation method as the most suitable to reconstruct the morphological features presented in nautical charts. The morphological evidences indicates that the basin-channel orientation, i.e., outflow configuration onto the ebb tidal delta and the Longshore Transport rate affect the headland-inlet bypassing mechanism. The first stage (1862–1941) revealed a volume gain along the Ebb tidal delta downdrift lobe. While the northwest channel and updrift coast were erosive, several deposits formed in the channel updrift side. This phase relies on sediment remobilization along the updrift coast and wave deposition dominance at the inlet's entrance and along the updrift channel side. The wave-dominance increase the nearshore headland bypassing and erode the downdrift channel bank, supplying the associated lobe. The second stage (1941–1972) was remarkable by accretion across the ETD. At the channel landward sector, cross-sectional asymmetry suggests the formation of a straighter ebb channel. This indicate the channel became dominated by tidal currents. On the other hand, wave-induced deposition dominated at the downdrift lobe, inducing a longshore transport reversal and an ETD sediment-trapping phase. During the third phase (1972–1995) the updrift channel sector was erosive, suggesting a longshore transport rate decreasing at the inlet's entrance and a ETD outer shoal bypassing. The fourth phase (1995–2021) was related to a higher LST rate, regarding the updrift coast was erosive and the landward channel compartment imputed sediment again.

本文提出了一个概念模型，用于研究巴西南部巴比通加湾由岬角控制的入海口的形态演变。本文汇编了多个历史测深数据集，时间跨度为 160 年（1862-2021 年）。对各种插值方法的测试表明，经验贝叶斯克里金插值法最适合重建海图上的形态特征。形态学证据表明，海盆-河道走向（即退潮三角洲上的流出配置）和长岸运移率影响着头岸-入海口绕流机制。第一阶段（1862-1941 年）揭示了退潮三角洲下移叶的体积增大。虽然西北航道和上漂海岸受到侵蚀，但在航道上漂一侧形成了一些沉积。这一阶段依赖于漂移上升沿岸沉积物的重新移动，以及入海口和漂移上升航道一侧的波浪沉积。波浪主导作用增加了近岸岬角，绕过并侵蚀了下漂航道堤岸，为相关波束提供了补给。第二阶段（1941-1972 年）的显著特征是整个 ETD 的增生。在航道向陆部分，横截面的不对称表明形成了一条较直的退潮航道。这表明该航道已被潮汐流所主导。另一方面，波浪引起的沉积在下漂叶片占主导地位，引起了长岸运移逆转和 ETD 沉积物捕集阶段。在第三阶段（1972-1995 年），上漂航道区段出现侵蚀，表明入海口处的长岸运移速率下降，ETD 外部浅滩绕行。第四阶段（1995-2021 年）与较高的 LST 率有关，这一时期，上漂海岸受到侵蚀，向陆水道区再次淤积沉积物。

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引用次数: 0

Seasonal mobility of transverse finger bars within a mixed sand-gravel bay measured using X-band Radar 利用 X 波段雷达测量沙砾混合海湾内横向指状条石的季节流动性

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-16 DOI: 10.1016/j.geomorph.2024.109517

Dominique Townsend , Julian Leyland , Hachem Kassem , Charlie E.L. Thompson , Ian H. Townend , Paul S. Bell , Cai O. Bird

Transverse finger bars have largely been associated with sandy coasts. Here we show that these features persist within a wider mixed sediment environment, adjacent to a shingle cuspate foreland, which has not been previously reported. Details of the bars' characteristics were gleaned from analysis of bathymetry data, whilst weekly migration rates were inferred from remote sensing of the sea surface roughness as a proxy of undulating bedforms, using X-band radar reflectance data. The bars were on average ~380 m long, had wavelengths of ~160 m, amplitudes of approximately 0.2 to 0.6 m and were orientated 30° to shore normal. They were found in water depths between −3.3 and −5.8 m Ordnance Datum. The bars migrated by approximately 150 m over the first ‘winter’ observation period (15/11/2020–02/04/2021) and 70 m in the following winter period (Sept 2021–Feb 2022) but showed virtually no signs of movement during the intervening summer months. Analysis of hydrodynamic conditions suggested the bar mobility was related to the dominant longshore currents resulting from high angle, south westerly waves. Low amplitude rhythmic bedforms were also found in the upper beach, migrating at a similar rate to the nearshore bars, which are thought to be driven by high-angle wave instability.

横向指状条纹在很大程度上与沙质海岸有关。在这里，我们展示了这些特征在更广阔的混合沉积物环境中持续存在，毗邻楔形滩涂前陆，这在以前的报告中还没有出现过。我们通过分析水深测量数据收集了条带的详细特征，同时利用 X 波段雷达反射数据，通过遥感海面粗糙度推断出了条带的周迁移率，以此来替代起伏的海床形态。条带平均长约 380 米，波长约 160 米，振幅约 0.2 至 0.6 米，方向与海岸线成 30°。它们出现在海拔标准-3.3 至-5.8 米之间的水深区域。在第一个 "冬季 "观测期间（2020 年 11 月 15 日至 2021 年 4 月 2 日），条形水柱移动了约 150 米，在接下来的冬季观测期间（2021 年 9 月至 2022 年 2 月），条形水柱移动了 70 米，但在其间的夏季观测期间，条形水柱几乎没有移动迹象。对水文动力条件的分析表明，横杆的移动与高角度西南波造成的主要长岸流有关。在上部海滩还发现了低振幅的节律床形，其迁移速度与近岸横杆相似，这被认为是由高角度波浪的不稳定性驱动的。

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引用次数: 0

Erosion processes and gravitational mass movements on Trindade Island, Brazil (South Atlantic Ocean) 巴西特林达德岛（南大西洋）的侵蚀过程和重力质量运动

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-16 DOI: 10.1016/j.geomorph.2024.109516

Fernanda Avelar Santos, Lázaro Valentin Zuquette, Rodolfo José Angulo, Maria Cristina de Souza, Adriana Ahrendt Talamini, Leonardo Mairink Barão, Herick Faust Daufenbach, Maurício Henrique Garcia

This study provides the first assessment of non-volcanic geohazards on Trindade Island, a remote South Atlantic territory 1140 km southeast of Brazil. The island's location, climate, relief, lithology, and natural processes like weathering, erosion, and deposition pose significant dangers to habitation and geoheritage. Our focus was on geological-geotechnical mapping to identify gravitational mass movements and erosive processes. Within the six units mapped, two primary contexts were identified. We observed active hydraulic erosion, such as gullies and alluvial fans, on slopes shaped by nephelinite lava flows interlayered with fragmented pyroclastic material. In contrast, phonolitic peak areas and pyroclastic breccia bedrock displayed gravitational mass movement deposits, such as avalanche rocks. Gravitational mass movements triggered by hydrological erosion processes are the main threat. The island's landscape evolution is primarily driven by natural processes, with human influence contributing since colonization. Thus, Trindade Island's landscape is shaped by both natural and anthropogenic factors. This study underscores the need for effective mitigation and protection measures to ensure the safety of Trindade Island's inhabitable areas. Integrating an analytical model and considering temporal variations in rainfall could enhance our understanding of non-volcanic hazards on oceanic islands.

这项研究首次对特林达德岛的非火山地质灾害进行了评估，该岛位于巴西东南 1140 公里处，是一块偏远的南大西洋领土。该岛的位置、气候、地形、岩性以及风化、侵蚀和沉积等自然过程对居住和地质遗产构成了巨大的威胁。我们的工作重点是绘制地质岩土图，以确定重力质量运动和侵蚀过程。在绘制的六个单元中，确定了两个主要背景。我们观察到，在霞石熔岩流与碎屑火成岩材料交错形成的斜坡上，存在着活跃的水力侵蚀现象，如冲沟和冲积扇。与此相反，辉绿岩峰区和火成碎屑岩基岩则呈现出雪崩岩等重力移动沉积物。水文侵蚀过程引发的重力物质运动是主要威胁。特林达德岛的地貌演变主要是由自然过程驱动的，自殖民化以来，人类的影响也起到了一定的作用。因此，特林达德岛的地貌是由自然和人为因素共同塑造的。这项研究强调，需要采取有效的缓解和保护措施，以确保特林达德岛可居住区的安全。整合分析模型并考虑降雨量的时间变化，可以增强我们对海洋岛屿非火山灾害的了解。

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引用次数: 0

Eastward drainage-divide migrations driven by the spatial variations in precipitation and tectonic uplift contribute to the formation of the Parallel Rivers in the Hengduan Mountains, Southeastern Tibet 降水量和构造隆升的空间变化导致的流域分水岭东移，促成了西藏东南部横断山脉平行河流的形成

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-13 DOI: 10.1016/j.geomorph.2024.109513

Fan Gao , Xibin Tan , Chao Zhou , Shuang Bian , Feng Shi

In the Hengduan Mountains (Southeastern Tibet), the south-draining Nmai Hka (Upper Irrawaddy), Nu (Upper Salween), Lancang (Upper Mekong), and Jinsha (Upper Yangtze) Rivers flow parallel and in proximity to each other, thus forming rather a unique geomorphic configuration (i.e., the Parallel Rivers). It has been suggested that this configuration is an outcome of tectonic shortening that “squeezed” the rivers together. Although the tectonic and surface processes in this region have been extensively studied, the processes that led to this configuration remain controversial. Here, we investigate the potential role of drainage-divide migration in forming the Parallel Rivers. We demonstrate, based on geomorphologic analysis of divide stability between the parallel rivers, that while the two western divides (Nmai-Nu, Nu-Lancang) are likely migrating eastward, the eastern divide (Lancang-Jinsha) is roughly stable. This pattern suggests that the formation of the Parallel Rivers is associated with an abutment of the migrating divides against the fixed one. GPS and precipitation data combined with prior research suggest that the migrations of the two western divides are driven by the spatial variations in precipitation and rock uplift. Concurrently the stability of the eastern divide is influenced by a combination of climatic and tectonic factors, as well as a historical river capture event. This implies that the formation of the Parallel Rivers has not necessarily been an outcome of east-west tectonic shortening but has been influenced by the spatial variations in precipitation and tectonic uplift.

在横断山脉（西藏东南部），南流的恩迈赫卡河（伊洛瓦底江上游）、怒江（萨尔温江上游）、澜沧江（湄公河上游）和金沙江（长江上游）相互平行，相互靠近，从而形成了一种独特的地貌构造（即平行河流）。有人认为，这种构造是构造缩短将河流 "挤压 "在一起的结果。尽管该地区的构造和地表过程已被广泛研究，但导致这种构造的过程仍存在争议。在此，我们研究了排水沟迁移在平行河流形成过程中的潜在作用。根据对平行河流之间分水岭稳定性的地貌分析，我们发现西部的两条分水岭（怒江-怒江、怒江-澜沧江）很可能在向东迁移，而东部的分水岭（澜沧江-金沙江）则基本稳定。这一模式表明，平行河流的形成与正在迁移的分水岭与固定分水岭的对接有关。全球定位系统和降水数据以及先前的研究表明，西部两个分水岭的迁移是由降水和岩石隆起的空间变化驱动的。同时，东部分水岭的稳定性受到气候和构造因素以及历史上河流截流事件的综合影响。这意味着平行河流的形成并不一定是东西构造缩短的结果，而是受到降水和构造隆升空间变化的影响。

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引用次数: 0

A hybrid, genetic programming and physically-based predictor of dune geometry 基于遗传编程和物理原理的沙丘几何形状混合预测器

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-12 DOI: 10.1016/j.geomorph.2024.109495

Arnaud Doré , Giovanni Coco

Subaqueous sand dunes are found in many natural environments and pose significant operational challenges. However, classic dune predictors found in the literature fail at predicting equilibrium dune dimensions. In this study, we first investigated the potential of using genetic programming to derive predictive equations of dune wavelength and height. The predictors outperformed existing relationships, yet the equations remain complex due to the intricate physics governing dune evolution. We carried out a global sensitivity analysis to evaluate the most influential parameters of the GP predictors. Finally, we proposed a set of robust predictors, for equilibrium dune heights and wavelengths, relying on basic environmental parameters.

许多自然环境中都存在水下沙丘，这给实际操作带来了巨大挑战。然而，文献中的经典沙丘预测方法无法预测沙丘的平衡尺寸。在这项研究中，我们首先研究了使用遗传编程法推导沙丘波长和高度预测方程的潜力。预测结果优于现有的关系，但由于沙丘演变的物理学原理错综复杂，预测方程仍然很复杂。我们进行了全局敏感性分析，以评估 GP 预测方程中最具影响力的参数。最后，我们提出了一套基于基本环境参数的沙丘平衡高度和波长的稳健预测方法。

引用次数: 0

Predicting urban channel morphology amidst multiple complexities 在多重复杂性中预测城市河道形态

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-12 DOI: 10.1016/j.geomorph.2024.109511

Lukman A. Soboyejo, Kathryn L. Russell, Tim D. Fletcher

Urbanisation has resulted in rapid geomorphic changes and ecosystem degradation in many streams worldwide. The question of how channel response to urbanisation can be accurately predicted amid multiple driving factors remains a significant scientific challenge. Numerous efforts have been made to address this issue over the past 80 years. Nevertheless, channel response resulting from urbanisation differs across physiographic regions, making it difficult to predict. The main goal of this study is to investigate the most important factors influencing morphological changes, such as channel area, in streams with urbanised catchments. To accomplish this aim, we reviewed the literature on the application of hydraulic geometry models to urban-impacted rivers worldwide. We set out to investigate two specific questions: (i) to what extent and under what circumstances can urban stream bankfull cross-sectional area be predicted by catchment area and impervious cover metrics? and (ii) is stream bankfull width more susceptible than stream bankfull depth to urban-induced enlargement? However, over 90 % of the urban channels studied in the literature we reviewed showed irregular response patterns to urbanisation, owing to the complex interplay of local factors, such as geology, sediment, hardpoints, and riparian vegetation. Our most important conclusion is that local context is an important controller of stream channel response to urbanisation. While catchment area is a good predictor of channel area in some urban sites, it is a poor predictor of channel area in other urban sites. This contrasts with non-urban sites, where catchment area usually predicts channel area more strongly. In addition, impervious cover alone, which represents the direct hydrological impact of urbanisation, is insufficient to fully explain channel enlargement and incision. Therefore, models of channel response to urbanisation must consider the specific local factors that drive or limit these responses in order to be effective as predictive and explanatory tools.

城市化导致全球许多河流的地貌迅速变化和生态系统退化。在多种驱动因素的作用下，如何准确预测河道对城市化的反应仍然是一个重大的科学挑战。在过去的 80 年中，人们为解决这一问题做出了大量努力。然而，城市化导致的河道响应在不同的地理区域存在差异，因此难以预测。本研究的主要目标是调查影响城市化集水区河道面积等形态变化的最重要因素。为了实现这一目标，我们查阅了有关将水力几何学模型应用于全球受城市影响河流的文献。我们着手研究两个具体问题：(i) 在何种程度上和何种情况下，城市河流的河岸横截面积可以通过集水面积和不透水覆盖率指标进行预测？ (ii) 与河岸深度相比，河岸宽度是否更容易受到城市引起的河道扩大的影响？然而，由于地质、沉积物、硬点和河岸植被等当地因素的复杂相互作用，在我们查阅的文献中，超过 90% 的城市河道对城市化的反应模式不规则。我们最重要的结论是，当地环境是河道对城市化反应的重要控制因素。在某些城市地区，集水区可以很好地预测河道面积，但在其他城市地区，集水区却不能很好地预测河道面积。这与非城市地区形成了鲜明对比，在非城市地区，集水面积通常能更准确地预测河道面积。此外，仅仅是不透水覆盖（代表城市化的直接水文影响）还不足以完全解释河道的扩大和内切。因此，河道对城市化反应的模型必须考虑驱动或限制这些反应的当地特定因素，才能有效地作为预测和解释工具。

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引用次数: 0

Topographic ridges express late Quaternary faulting peripheral to the New Madrid seismic zone, intraplate USA: Their tectonic implications 美国板块内新马德里地震带外围第四纪晚期断层的地形山脊：其构造影响

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2024-11-08 DOI: 10.1016/j.geomorph.2024.109502

S. Pinardi , R.T. Cox , D. Leslie , Md.R. Hasan , N. Adhikari , R.B. Van Arsdale

Northeast-trending linear topographic ridges in Pliocene and Quaternary sediments adjacent to the New Madrid seismic zone (NMSZ), intraplate North America, have been long speculated to be neotectonic landforms related to reactivation of basement faults of the eastern Mississippi Valley Rift margin. Earthquake epicenters and paleoseismological studies show that eastern rift margin faults (ERMF) were active during late Quaternary south of a restraining bend in the Mississippi Valley Rift fault complex, but the ERMF zone north of the restraining bend (ERM-N) and underlying the linear ridges is seismically quiescent. A previous P-wave seismic reflection survey across the most prominent linear ridge (Rives lineament) revealed that it overlies a horst in Eocene sediment. To ascertain whether the Rives lineament could have been produced by surface faulting/folding, we collected electrical resistivity tomography (ERT) and ground penetrating radar (GPR) profiles to image the ridge's shallow subsurface features. We interpret shallow folding and faulting of late Pleistocene sediment in our ERT and GPR images. Additionally, convexity of multiple topographic profiles of scarps along margins of the Rives lineament was quantified and compared to the convexity of profiles of known neotectonic scarps and of fluvial terrace riser profiles within the region. Comparison of these profiles reveals a high degree of similarity between the scarps along the Rives lineament margins and the Holocene Reelfoot thrust scarp. When combined, our results strongly suggest late Pleistocene or Holocene folding and faulting created this ridge despite its current seismic quiescence, and thus they provide useful insight for assessing the seismic hazard potential of quiescent faults in strike-slip systems in general. We conclude that the late Quaternary series of movements documented on the Reelfoot thrust was initiated to accommodate crustal shortening after transpressional fault movements on the ERM-N became inactive in late Pleistocene or early Holocene and that movement along the ERM-N may resume if the Reelfoot thrust has an interval of inactivity in the future. Our results suggest how fault interactions within a strike-slip system can change, making faults with significant amounts of seismic potential appear as though they are inactive.

长期以来，人们一直推测毗邻北美板块内部新马德里地震带（NMSZ）的上新世和第四纪沉积物中的东北走向线状地形山脊是与密西西比河谷裂谷东缘基底断层重新活化有关的新构造地貌。地震震中和古地震学研究表明，密西西比河谷裂谷断裂复合体约束弯以南的东部裂谷边缘断层（ERMF）在第四纪晚期十分活跃，但约束弯以北的ERMF区（ERM-N）和线性山脊下层则处于地震静止状态。之前对最突出的线性山脊（里夫线）进行的 P 波地震反射勘测显示，该山脊覆盖在始新世沉积物的一个地角之上。为了确定里夫斯线状构造是否由地表断层/褶皱产生，我们采集了电阻率层析成像（ERT）和地面穿透雷达（GPR）剖面图，对该脊的浅表次表层特征进行成像。我们在 ERT 和 GPR 图像中解释了晚更新世沉积物的浅层褶皱和断层。此外，我们还对里夫斯线边缘疤痕的多个地形剖面的凸度进行了量化，并将其与该地区已知新构造疤痕和河流阶地隆起剖面的凸度进行了比较。对这些剖面进行比较后发现，里夫斯褶皱带边缘的疤痕与全新世的里尔富特推力疤痕具有高度的相似性。综合这些结果，我们强烈认为晚更新世或全新世的褶皱和断层造成了这一山脊，尽管它目前处于地震静止状态，因此它们为评估一般走向滑动系统中静止断层的地震危险潜力提供了有用的见解。我们的结论是，记录在案的第四纪晚期里尔富特推力上的一系列运动是在更新世晚期或全新世早期ERM-N上的转压断层运动不活跃之后为适应地壳缩短而开始的，如果里尔富特推力在未来有一段时间不活跃，ERM-N上的运动可能会恢复。我们的研究结果表明，走向滑动系统中的断层相互作用可能会发生变化，从而使具有巨大地震潜力的断层看起来似乎处于不活跃状态。

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