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A coordinated multi-year ocean exploration campaign on the Blake Plateau offshore of the southeastern U.S. has mapped what appears to be the most expansive cold-water coral (CWC) mound province thus far discovered. Nearly continuous CWC mound features span an area up to 500 km long and 110 km wide, with a core area of high-density mounds up to 254 km long by 42 km wide. This study synthesized bathymetric data from 31 multibeam sonar mapping surveys and generated a standardized geomorphic classification of the region in order to delineate and quantify CWC mound habitats and compare mound morphologies among subregions of the coral province. Based on the multibeam bathymetry, a total of 83,908 individual peak features were delineated, providing the first estimate of the overall number of potential CWC mounds mapped in the region to date. Five geomorphic landform classes were mapped and quantified: peaks (411 km2), valleys (3598 km2), ridges (3642 km2), slopes (23,082 km2), and flats (102,848 km2). The complex geomorphology of eight subregions was described qualitatively with geomorphic “fingerprints” (spatial patterns) and quantitatively by measurements of mound density and vertical relief. This study demonstrated the value of applying an objective automated terrain segmentation and classification approach to geomorphic characterization of a highly complex CWC mound province. Manual delineation of these features in a consistent repeatable way with a comparable level of detail would not have been possible.

Diatomite deposits of the lacustrine Truckee Formation near Hazen, Northern Nevada, are of Miocene age (ca. 10.3 million years old) and consist of varved deposits within commercial mines. These exposed deposits have been primary source of paleontological samples of stickleback fish fossils (Gasterosteous doryssus) spanning 100,000 years. These samples have revealed stasis, rapid morphological and genetic evolution, and local extinction of G. doryssus against a background of changing diatom communities. Here, we draw on geological, limnological, anthropogenic, and bibliographical data to illustrate the geographic and paleontological context of the Hazen diatomite deposits. We include a stratigraphic section describing lithology and stickleback specimen frequency at a 1 mm resolution. This paper should help researchers identify patterns in fossil site distribution and better understand the geological processes that have shaped the area, spurring new sampling and future research.

In this study, the variance seismic attribute was used to track fault geomorphology, which interpreted in time. To convert these fault surfaces and isochron maps to depth, the velocity model was prepared. Therefore, 14 velocity models for depth conversion were built by using different equations in East Baghdad Field, central Iraq to depth conversion assessment and select a precise model from many candidates of velocity models to generate an accurate depth map. All the velocity models are divided into two main velocity layers. The upper-velocity layer represents the tertiary sequences, while the lower-velocity layer represents the Upper Cretaceous sequences. Three criteria are made in this study (mis-tie value, standard deviation analysis, and blind well test) to select the best depth map. The results reveal the velocity model-7 is better to use because the depth map of the Khasib Reservoir, which produced from model-7 shows less mis-tie between estimated and real depth, less standard deviation values, and lower errors at EB 24 and 26 well locations. The corrected depth map of Khasib Reservoir shows three structure noses. Two of them opened toward the NW direction, while the southern structural nose opened toward the SW direction with a minor enclosure. [ABSTRACT FROM AUTHOR]

According to national climate resilience projections, the coastal area of Bolaang Mongondow has experienced an increase in wave height of around 1 meter. It is in the top priority category with high potential hazards and vulnerability or risk of climate change disasters. The rise of the global sea level affects the increase in coastal submergence and erosion and increases the frequency of overtopping of coastal buildings. This research aimed to analyze the extent of the physical vulnerability of coastal Bolaang Mongondow related to the climate change impacts. The coastal area of Bolaang Mongondow was chosen because it is a coastal area with varied lowlands that directly face the Sulawesi Sea (Pacific Ocean). The vulnerability assessment method used in this study was calculating the Coastal Vulnerability Index (CVI). Spatial data interpretation of the parameters of coastal geomorphology, elevation, coastal slope, shoreline change, sea level rise, tides, and significant wave height will contribute to the final vulnerability index value. The results showed that the weight of each analyzed variable varied, ranging from not vulnerable, moderate, vulnerable, and very vulnerable. The CVI assessment shows the less vulnerable category class in all analyzed coastal areas, with index values of 5.86 in Poigar District, 13.1 both in East Bolaang and Bolaang Districts, 14.6 in Lolak District, and 6.55 in Sangtombolang District. Thus, this research concludes that the physical condition of the Bolaang Mongondow coast is less vulnerable to the impacts of climate change. However, it is still threatened in several specific aspects. Although it has not considered socio-economic factors, the assessment of the physical vulnerability of the Bolaang Mongondow coastline produced in this study can be used to formulate targeted mitigation strategies and adaptation measures in the area. [ABSTRACT FROM AUTHOR]

Urban geomorphology is a recent discipline that has gained a great deal of interest amongst the scientific community also for its clear connection with the concept of Anthropocene. The identification of anthropogenic landforms in an urban area requires a multidisciplinary approach, mostly using multi-temporal map comparisons, direct and indirect geognostic surveys, and detailed study of the urban landscape. Mediterranean cities have a particularly complex history: their original settlement usually dates back to the medieval period, but often to more ancient, occasionally even prehistoric, times. The result is an urban landscape characterised by modified natural landforms, but above all by anthropogenic landforms linked to the stratification of various urban phases. Reconstructing the landforms before major anthropogenic impacts of the last centuries is a particularly complex operation, and scientific research appears in its early stages. In this research, we introduce examples of the reconstruction of natural landforms in the historic centre of Genoa, a port city that experienced a peak of expansion in the Middle Ages and the Modern Age. The results obtained on four pilot areas highlight significant and previously unknown anthropic modifications and the associated landforms in the urban landscape. Large excavations, fills supported by ramparts, and sea embankments have been identified and quantitatively evaluated using a mixed approach between different disciplines: historical geography, geomatics, physical geography and geomorphology, and engineering geology. This methodology may be applied to other Mediterranean and extra-European urban contexts and may contribute, on the one hand, to the identification of potential geomorphological risks in urban areas and, on the other hand, to the use of urban landscape forms for geological heritage and geodiversity development activities. [ABSTRACT FROM AUTHOR]

Fluvial geomorphologists' advocacy for a culture of care towards rivers is increasingly animated by the potentialities of hyperscale environmental data. Championing catchment-specific responses, it has been argued that intensified datafication of rivers can help them express their own voice. Motivated by this provocation, this paper discusses prosthetic research encounters with the River Feshie in Scotland to tentatively approach the question 'what is a river's voice' in a moment of increasing digitisation and automation of geomorphological fieldwork via technologies of light. Exploring the allowances and excesses of illumination in the scientific imaging of the Feshie, it draws on 'critical physical geography' and 'feminist new materialism' to conceptualise the geovisualisation of riverscapes as a partial practice of envisioning, rather than a process of total illumination. By highlighting the multiplicity of riverine voices that become co-produced through differently configured sensing ensembles, the paper advocates for a critical fluvial geomorphology that interrogates its assumptions about access to the 'real'. [ABSTRACT FROM AUTHOR]

In recent years, the study of geoheritage has gained global importance, and in the case of Costa Rica, the first investigations have been carried out to identify geosites, as well as the interest in establishing a geopark in the La Amistad-Pacífico Conservation Area. This research focuses on identifying, analyzing, and evaluating the geosites in the Altamira Sector of the La Amistad International Park (PILA, in Spanish) to understand their state of geoconservation and their potential for geotourism. The methodology consists of three steps: geosites identification through geomorphological mapping, fieldwork, and bibliographic research; historical-cultural characterization using documentation related to natural history, expeditions, art, and sacred sites; and geosites evaluation based on criteria such as form, condition, ecosystems, management, and conservation, as well as their relevance to geotourism and their impact on local communities. Four geosites were identified in the Altamira sector: Valley of Silencio, Kamuk Hill, Gemelo-Pittier Hills, and The Esperanza savanna. These geosites feature valleys dissected by channels due to fluvial processes, as well as landscapes shaped by steep volcanic slopes, river action, and periglacial processes. Historical-cultural references were found, including artistic documents, legends, and stories linking them to Costa Rican indigenous culture. Geosites evaluation revealed high scores in criteria related to intrinsic values that define these sites as highlights of geoheritage due to their unique characteristics. However, weaknesses were identified in the Use and Management criteria, primarily in terms of infrastructure to promote geotourism. It is concluded that the selected geosites are representative of their geological and geomorphological evolution, housing valuable information about the natural processes that shaped the territory and serving as evidence of the country's natural and cultural history. Additionally, they stand out as suitable places to promote geoheritage conservation through activities such as research, education, cultural events, and geotourism. [ABSTRACT FROM AUTHOR]

The Himalayas significantly impact local and regional hydro-sedimentary processes and weathering rates. Utilizing geomorphometric anomalies offers insights into the connections between topographic factors and rates of cation weathering and sedimentary flux. An empirical model RS-GIS tool was used to compute the runoff and weathering rates of the basin. The 6th-order Lolab River with 451 different lower-order streams is dominated by dendritic to semi-dendritic draining patterns with the presence of steep slopes. The linear aspects of the basin showed the drainage pattern is influenced by geological and lithological factors. Additionally, other parameters such as rotundity factor, circulation factor, compactness coefficient, and elongation ratio indicate an elongated shape, reduced peak flow, and a complex structure. The significant reduction in Runoff (Q) and Sediment Production Rate (SPR) within the Lolab basin, measuring 4.61 sq km-cm/sq km and 0.17 ha-m/100-sq km/year respectively, suggests minimal runoff and reduced soil erosion. These findings can provide valuable information about weathering, erosion, and sediment delivery processes. This data helps understand how environmental changes and natural hazards affect the fragile Himalayan landscape and aids in regional land management decisions for sustainable land use policies. [ABSTRACT FROM AUTHOR]

The Shyok Valley, within the Upper Indus Basin in Trans-Himalayas, lies in the cold and arid region. It is fed by the Siachen glacier; the largest glacier in the third pole. The fluctuations in this glacier are attributed to varying intensities of the two weather regimes namely mid-latitude westerlies and Southwest Monsoon. The reconstruction of the magnitude, timing, and landscape impact of glaciers in Nubra-Shyok valley have been explored in past decade yet they are contentious and uncertain. Therefore, the present study investigates the sediments from the key sites (Agham, Khardung, Changmar, Chalunka) in the Shyok valley using Optically Stimulated Luminescence (OSL) dating technique. The diverse geomorphology, including moraines, sand dunes, mass movement zone, alluvial fans are mapped to represent the geomorphic setting of the region. The chronological ages from the lower Shyok Valley (Agham section: 18.4 ± 2.2 ka) suggest extensive glacier expansion beyond the present terminus of the Siachen Glacier during the Marine Isotopic Stage (MIS)-2. The Khardung section has glaciofluvial deposits: 24.0 ± 2.4 ka (KHG-1), younger moraine: 8.2 ± 1.0 ka (KHG-9) and lacustrine deposits (KHGL-5, KHGL-6, KHGL-7): 14.1 ± 2.0 ka, 12.1 ± 1.1 ka, 10.7 ± 1.3 ka. The glacial events that occurred around 8.2 ka and 12.0 ka suggest glacial advancement which are likely due to a period of lower temperature. The Changmar section displays lacustrine deposits and debris flow events dated to the late glacial (14.5 ± 1.7 ka, CHG-1; 13.2 ± 1.6 ka, CHG-2) and deglaciation period (6.5 ± 1.2 ka, CHG-3; 5.5 ± 1.0 ka, CHG-4). The presence of the Holocene-aged lateral moraines (20 km away from Chalunka village: 14.3 ± 1.3 ka, CLM-2; 5.7 ± 0.9 ka, CLM-3; 0.4 ± 0.04 ka, CLM-4) and CHG-8: 2.1 ± 0.3 ka; outwash plain deposits: COP-7: 2.4 ± 0.4 ka aligns with the previous findings in the Nubra Valley, suggesting glacial advance in Little Ice Age in the whole valley. The glacial event occurring between 2.4 and 2.1 ka corresponds to the Neoglacial epoch, characterized by a glacial advance likely caused by a decrease in temperature during the late Holocene period. The intensified mid-latitude westerlies during MIS-2 are inferred to be the key factor in increased moisture to the Shyok Valley which led to the glacier expansion. These findings enhance our understanding of past climate changes in this high-altitude region and serve as a valuable baseline for future studies on glacial response to climate variations. [ABSTRACT FROM AUTHOR]

The characterization of natural hazards in coastal environments is of great necessity, especially in the current context of global climate change and increasing population concentrations. This research focuses on a multi-hazard analysis of the main geotechnical, geomorphological, hydrological, and lithological risks in the southeastern margin of the Ría de Arosa using Geographic Information System techniques. The integration of geotechnical characterization maps and natural hazard maps has allowed for the identification of areas with a high susceptibility to natural disasters, which is crucial for territorial planning and management in the context of growing urban pressure and global climate change. The results indicate that poorly consolidated surface formations, especially in transitional areas such as dunes and marshes, are particularly vulnerable. Additionally, areas with higher lithological competence have been identified, where slope changes contribute to ground instability. This analysis provides valuable tools for decision-making and the implementation of risk management policies, promoting sustainable development, the protection of coastal ecosystems, and the prevention of risks from urban planning and civil engineering activities in the Ría de Arosa. [ABSTRACT FROM AUTHOR]

Although erosion has naturally been driven by rainfall patterns, human activities have increasingly influenced erosion rates in recent times. However, as climate change alters precipitation, future erosion control may once again depend primarily on climate. The primary goal of this investigation was to ascertain whether the issue of escalated erosion, typically linked to downstream dam effects, could diminish in significance due to projected climatic shifts later in this century. An erosion potential index (Ep), formulated as the ratio of the mass of sediment influx from upstream to the frequency of the sediment-carrying flow events, was computed on a tributary of the Godavari River, located downstream of a dam. Using the Soil & Water Assessment Tool (SWAT), virtual experiments were conducted to distinguish the impacts of the dam from projected climate changes on river geomorphology. Two control scenarios were created using the current climate data and simulated regulated and unregulated states of the basin. Employing climate projections and various mitigation scenarios (SSPs) for the 2060s and 2090s, this study estimated Ep values exclusively under future climatic conditions in an unregulated state of the basin. Results indicate that, in the unregulated state without the existence of the upstream dam, future climate impacts on erosion outweigh the current effects of the dam, underscoring the growing influence of climate on geomorphology. It suggests that existing structural interventions may lose their geomorphic significance in the face of future climate conditions. [ABSTRACT FROM AUTHOR]

Predicting the nearshore sediment transport and shifts in coastlines in view of climate change is important for planning and management of coastal infrastructure and requires an accurate prediction of the regional wave climate as well as an in-depth understanding of the complex morphology surrounding the area of interest. Recently, hybrid shoreline evolution models are being used to inform coastal management. These models typically apply the one-line theory to estimate changes in shoreline morphology based on littoral drift gradients calculated from a 2DH coupled wave, flow, and sediment transport model. As per the one-line theory, the calculated littoral drift is uniformly distributed over the active coastal profile. A key challenge facing the application of hybrid models is that they fail to consider complex morphologies when updating the shorelines for several scenarios. This is mainly due to the scarcity of field datasets on beach behavior and nearshore morphological change that extends up to the local depth of closure, leading to assumptions in this value in overall shoreline shift predictions. In this study, we propose an improved hybrid model for shoreline shift predictions in an open sandy beach system impacted by human interventions and changes in wave climate. Three main conclusions are derived from this study. First, the optimal boundary conditions for modeling shoreline evolution need to vary according to local coastal geomorphology and processes. Second, specifying boundary conditions within physically realistic ranges does not guarantee reliable shoreline evolution predictions. Third, hybrid 2D/one-line models have limited applicability in simple planform morphologies where the active beach profile is subject to direct impacts due to wave action and/or human interventions, plausibly due to the one-line theory assumption of a constant time-averaged coastal profile. These findings provide insightful information into the drivers of shoreline evolution around sandy beaches, which have practical implications for advancing the shoreline evolution models. [ABSTRACT FROM AUTHOR]

This article attempts to interpret folk narratives featuring the motif of producing millstones from erratic boulders and their subsequent reuse in new functional contexts. According to our assumptions, in folk narratives originating from the northern regions of Germany and Poland, where these motifs are present, one can find references to the methods of obtaining stone materials characteristic of these areas. These narratives also include information about the occurrence of erratic boulders – consistent with the geomorphology of regions affected by the last glaciation, and residual information regarding the distribution of millstones as well as semi-finished products. Thus, folk narratives can often serve as an interesting point of reference not only for ethnologists and folklorists but also for geologists and geographers. [ABSTRACT FROM AUTHOR]

Multibeam echosounders provide ideal data for the semi-automated seabed feature extraction and accurate morphometric measurements. In this study, bathymetric and raw backscatter data were initially used to manually delimit the reef morphologies found in an insular semi-enclosed gulf in the northern Aegean Sea (Gera Gulf, Lesvos Island, Greece). The complexity of this environment makes it an ideal area to "crash test" (test to the limit) and compare the results of the delineation methods. A large number of (more than 7000) small but prominent reefs were detected, which made manual mapping extremely time-consuming. Three semi-automated tools were also employed to map the reefs: the Benthic Terrain Modeler (BTM), Confined Morphologies Mapping (CoMMa), and eCognition Multiresolution Segmentation. BTM did not function properly with irregular reef footprints, but by modifying both the bathymetry and slope, the outcome was improved, producing accurate results that appeared to exceed the accuracy of manual mapping. CoMMa, a new GIS morphometric toolbox, was a "one-stop shop" that, besides generating satisfactory reef delineation results (i.e., detecting the same total reef area as the manual method), was also used to extract the morphometric characteristics of the polygons resulting from all the methods. Lastly, the Multiresolution Segmentation also gave satisfactory results with the highest precision. To compare the final maps with the distribution of the reefs, mapcurves were created to estimate the goodness-of-fit (GOF) with the Precision, Recall, and F1 Scores producing values higher than 0.78, suggesting a good detection accuracy for the semi-automated methods. The analysis reveals that the semi-automated methods provided more efficient results in comparison with the time-consuming manual mapping. Overall, for this case study, the modification of the bathymetry and slope enabled the results' accuracy to be further enhanced. This study asserts that the use of semi-automated mapping is an effective method for delineating the geomorphometry of intricate relief and serves as a powerful tool for habitat mapping and decision-making. [ABSTRACT FROM AUTHOR]

The document is an article from the Journal of Coastal Research, focusing on Fowlers Bay in South Australia. It provides information about the bay's history, including its use by whalers in the 18th and 19th centuries, the establishment of a landing and port in the 1860s, and its subsequent decline and revitalization through tourism. The article also describes the bay's current features, such as seagrass meadows, dunes, and ongoing efforts to stabilize the dunes. [Extracted from the article]

Clarifying the response relationship between soil radon gas anomalies and active fault tectonic geomorphology, and to explore a rapid prediction method for concealed fractures, soil radon gas measurements and unmanned aerial vehicle micro-geomorphic scanning were carried out in the basin section of the Aba South Fault in western Sichuan. The areas of radon gas anomalies and tectonic features formed by fracture activities are highly consistent with the distribution areas of hidden fractures. It is concluded that the combination of soil radon gas measurements and tectonic geomorphologic analysis can rapidly and accurately predict hidden fractures covered by Quaternary sediments. [ABSTRACT FROM AUTHOR]

Natural seafloor depressions, known as pockmarks, are common subaqueous geomorphological features found from the deep ocean trenches to shallow lakes. Pockmarks can form rapidly or over millions of years and have a large variety of shapes created and maintained by a large variety of mechanisms. In the sandy sediments of the southeastern North Sea, abundant shallow pockmarks are ubiquitous and occur at shallow water depths (<50 m). Their formation has previously been linked to methane seepage from the seafloor. Here, we characterize over 50,000 pockmarks based on their morphology, geochemical signature, and the subsurface pre‐conditions using a new integrated geoscientific data set, combining geophysical and sedimentological data with geochemical porewater and oceanographic analysis. We test whether the methane seepage is indeed responsible for pockmark formation. However, our data suggest that neither the seepage of light hydrocarbons nor groundwater is driving pockmark formation. Because of this lack of evidence for fluid seepage, we favor the previously suggested biotic formation but also discuss positive feedback mechanisms in ocean bottom currents as a formation process. Based on a comparison of pockmarks to the central and southeastern North Sea, we find that local lithology significantly affects pockmark morphology. Muddy lithologies favor the formation of larger, long‐lived structures, while sandy lithologies lead to short‐lived, small‐scale structures that are large in area but with shallow incision depth. We conclude that pockmarks in sandy environments might have been overlooked globally due to their shallow incision depth and recommend reevaluating the role of hydrocarbon ebullition in pockmark formation. Plain Language Summary: Pockmarks are natural depressions on the seafloor, found everywhere from deep oceans to shallow lakes. These underwater features can form quickly or over millions of years, sometimes reaching impressive sizes—tens of meters deep and kilometers wide. Pockmarks are created by different processes depending on where they are found, but they are often linked to the release of gases such as methane from the seafloor. In the southeastern North Sea, thousands of shallow pockmarks have been discovered in sandy areas less than 50 m deep. Initially thought to be caused by methane gas leaks, our research shows this is unlikely. We studied over 50,000 pockmarks using geological, chemical, and oceanographic data and found little evidence that methane or groundwater seepage is responsible. Instead, these pockmarks are more likely created by either marine animals such as harbor porpoises or turbulent ocean currents. We also found that the grainsize of the sediment greatly affects pockmark morphology and lifespan. In muddy areas, pockmarks are larger and longer‐lasting, whereas in sandy areas, they are shallower and shorter‐lived. Our findings suggest that many pockmarks in sandy environments may have been overlooked due to their shallow depth. We recommend reconsidering the role of methane in pockmark formation. Key Points: Pockmarks in the German Bight form in sandy environments and are likely not related to fluid ventingPockmarks in sandy sediments are shallow in depth, large in area and short‐lived structures compared to muddy host sedimentsDespite the widespread occurrence of pockmarks in the southeastern North Sea, the processes leading to their formation remain unclear [ABSTRACT FROM AUTHOR]

The study of active fault zones is fundamental to understanding both long‐term tectonics and short‐term earthquake behavior. Here, we integrate lidar‐enabled geomorphic‐geologic mapping and petrochronological analysis to reveal the slip‐history, tectonic evolution, and structure of the southern Alpine Fault in New Zealand. New petrographic, zircon U‐Pb and zircon trace‐element data from fault‐displaced basement units provides constraint on ∼70–90 km of right‐lateral displacement on the presently active strand of the southern Alpine Fault, which we infer is of Plio‐Quaternary age. This incremental displacement has accumulated while the offshore part of the fault has evolved within a distributed zone of plate boundary deformation. We hypothesize that pre‐existing faults in the continental crust of the Pacific Plate have been exploited as components of this distributed plate boundary system. Along the onshore southern Alpine Fault, detailed mapping of active fault traces reveals complexity in geomorphic fault expression. Our analysis suggests that the major geomorphic features of the southern Alpine Fault correspond to penetrative fault zone structures. We emphasize the region immediately south of the central‐southern section boundary, where a major extensional stepover and restraining bend are located along‐strike of each other. We infer that this geometry may reflect segmentation of the Alpine Fault between two distinct fault segments. The ends of these proposed segments meet near where several Holocene earthquake ruptures have terminated. Our new constraints on the evolution and structure of the southern Alpine Fault help contribute to improved characterization of the greatest onshore source of earthquake hazard in New Zealand. Key Points: Fiordland‐derived crystalline basement units have been dissected and dextrally displaced ∼70–90 km by the Alpine Fault since the late PlioceneThe southern Alpine Fault has evolved within a distributed fault network and may be less mature than the more northern parts of the faultStructural complexity where many Holocene earthquakes have terminated appears consistent with structural segmentation of the fault [ABSTRACT FROM AUTHOR]

Mountain meadows are ecologically important groundwater dependent ecosystems that retain and store water in upland forested landscapes. They tend to occur in low gradient, broad valleys where water slows and sediment accumulates, making them efficient locations for restoration. Over a century and a half of land use has degraded many meadows in the Sierra Nevada, reducing their hydrological and ecological functionality. Process‐based restoration (PBR) is an ecosystem rehabilitation approach that utilises biogeomorphic processes to facilitate functional ecosystem recovery. Low‐tech applications of PBR leverage fluvial processes, plant growth and the manipulation of onsite materials to increase structural and hydrological complexity. In meadows, typical goals associated with restoration are to increase groundwater elevations, expand wetted area, encourage sediment capture and create diffuse flow paths leading to improved ecological function over time. This study compares surface and groundwater conditions in a degraded riparian meadow in the Sierra Nevada, California, USA for 1 year before and after process‐based restoration to understand initial changes in meadow hydrogeomorphic function. Restoration included the installation of 39 postless beaver dam analog structures in ~1 km of incised meadow channel. Stage‐discharge data at the inlet and outlet of the project area were paired with groundwater data collected from 13 wells distributed across the meadow to estimate increased water storage of 3700 m3 due to restoration. After the wet winter of 2023, we estimated that pools upstream of structures filled to over half their volume with fine sediment. We also applied hydrodynamic modelling to evaluate fluvial changes at high flows and found that restoration increased flow complexity and wetted surface area. These short‐term responses highlight the potential speed and ability of low‐tech, process‐based restoration in achieving restoration outcomes. [ABSTRACT FROM AUTHOR]

Mountains are unique terrestrial ecosystems characterized by distinct physiography, biological diversity, and socio-economic features. These ecosystems provide numerous essential goods and services to communities within and beyond the mountains. Despite their significance, comprehensive studies that thoroughly characterize the ecosystem services of mountains are lacking. Such research is crucial to advance scientific understanding of mountain characteristics and ecosystem services. This study investigates mountain regions' unique characteristics and ecosystem services using global datasets such as the U.S. Geological Survey (USGS), the Global Mountain Biodiversity Assessment (GMBA), NASA EARTHDATA, and other relevant databases and literature review. The focus was to explore unique physiographic and socio-economic characteristics and ecosystem services provided by mountains. The results indicate that mountain ecosystems are pivotal in offering provisional, regulatory, and supporting ecosystem services on Earth. Despite their limited geographical area, these ecosystems supply substantial amounts of freshwater to communities living within and downstream of mountainous regions. Additionally, mountain ecosystems serve as global biodiversity hotspots, harboring a significant proportion of the world's species. However, mountain ecosystems face numerous natural and anthropogenic challenges, including climate change, habitat destruction, and resource overexploitation. Current efforts towards sustainable mountain development are inadequate. Enhanced scientific research and targeted policy measures are essential to address these challenges, protect mountain biodiversity, and ensure the continuous provision of vital ecosystem services. [ABSTRACT FROM AUTHOR]

The pore space characteristics of geological materials are closely related to their mechanical, transport and hydraulic properties. In geomorphology, pore size distribution (PSD) is an important characteristic in rock weathering, evaporation and other studies. In an effort to find novel methods to determine the PSD, perhaps to bypass the disadvantages of the current techniques, there has been a growing interest in the use of non‐Newtonian fluids. In this contribution, we are particularly interested in the method recently introduced by Abou Najm and Atallah (the ANA method), which exploits the way in which the flow of different shear‐thinning fluids distributes differently in the pore space to compute the functional PSD estimation. We performed a set of saturated flow experiments with aqueous xanthan gum solutions of different concentrations, using as simple as possible laboratory settings, and we implemented a modified version of the previously introduced numerical model to obtain the PSDs of four sandstone and one tuff samples. The results are compared with conventional mercury intrusion porosimetry, showing a good agreement regarding the dominant pore size and a notable similarity in the distributions. Several limitations were identified as well, such as the lack of information on relatively small pores (<5–10 μm for the samples studied) and the potential issues in obtaining a more detailed distribution. We conclude that the ANA method is promising for geomorphological evaporation and rock durability studies, particularly for coarser materials such as sandstone, but it also encounters challenges for certain applications, especially for fine‐grained rocks. It must be acknowledged that the ANA method has been tested on a limited range of materials and further investigation is required to fully explore its capabilities and limitations. [ABSTRACT FROM AUTHOR]

Assam, located in the Northeast of India, is highly flood-prone, and the erosional and depositional processes highly influence the landforms. The formation and development of landforms are directly related to the geology, geomorphology, drainage basin characteristics, and soil types of the region. In the present study, a remote sensing and GIS-based geomorphodiversity index (GMI) assessment of Assam is performed using three sub-indices: geodiversity, morphometric diversity, and drainage diversity index. Sixty-six potential geomorphosites are identified with their geological, geomorphological, and GMI classes. With the help of a flood inundation map, the inundated area of each GMI class is calculated. According to the result, 27.02%, 10.76%, and 3.7% of the total area of Assam fall under moderate, high, and very high GMI classes, respectively. Barak Valley and Central Assam region exhibit high to very high GMI values. Geology and geomorphology have a strong influence on GMI values. About 22.32%, 28.33%, 37.18%, 38.25%, and 35.37% of areas with low, moderate, high, and very high GMI are inundated, respectively. This study determined that areas having high GMI can increase the geomorphological heritage value of the region and can play a significant role in promoting geotourism with an increase in the scientific, educational, and aesthetic value of geomorphosites. This study can also help the local governing authorities to conduct and implement better management and conservation policies for vulnerable locations. [ABSTRACT FROM AUTHOR]

Mass movements can be caused by factors from different categories, such as geological factors and climate change. From a geological point of view, the soil profile and the geotechnical properties of the materials are crucial in influencing slope instability. From a climate change perspective, rainfall intensity is one of the main triggers of mass movements. Studies related to rainfall infiltration focus on saturated slope zones; therefore, areas of slope stability with infiltration in the unsaturated zone present large gaps. The Brazilian government environmental diagnostics company, the Mineral Resources Research Company (CPRM), identified the municipality of Areia/PB as a danger zone. The region has landslides that occur mostly during the rainy season. Such events lead to the presumption that rainwater infiltration is responsible for the failure of the municipality's slopes. Thus, the studies proposed in this research aim to determine the influence of precipitation on the stability of the slopes present in the region. The results show that antecedent precipitation has a greater influence on stability, indicating that daily precipitation alone cannot be used as a determinant for landslides. It was concluded that the role of precipitation in slope stability will vary for different locations, with varying surface conditions, variable tropical rainfall, or different microclimatic conditions. [ABSTRACT FROM AUTHOR]

Direct and indirect human disturbances present major challenges to sustainable management of dryland rivers, impacting upon their role as critical lifelines in arid and semiarid regions. This paper presents an overview of changing human–river relations, knowledges and practices in the management of dryland rivers in western India over the last 4500 years. In ancient times, traditional knowledges underpinned local water harvesting techniques that worked with nature. Subsequent imposition of external values and knowledge frameworks in colonial times applied a command‐and‐control ethos that asserted human authority over rivers. Postindependence, development programmes in the second half of the 21st century further accentuated this legacy, with profound implications for river health. Discipline‐bound approaches to river restoration in recent decades have failed to address these concerns. Using the Sabarmati catchment (~20,000 km2) as a case study, we develop a holistic, transdisciplinary approach that integrates traditional place‐based knowledges and practices alongside scientific understandings and the generative potential of Big Data to show how a plural knowledges model can support proactive and precautionary approaches to sustainable river management. [ABSTRACT FROM AUTHOR]

The Clarence River (New South Wales, Australia) was the main transport corridor for the timber and sugar cane industries operating in the catchment from the 1860s to the 1970s. Using archaeological, documentary, and oral historical resources we explore some of the anthropogenic impacts of these industries upon the fluvial geomorphology of the lower Clarence River. In particular, the deliberate abandonment of obsolete vessels on the river system is a focus. These discarded former cane and timber barges have been used as erosion control devices in several areas around the Harwood Island sugar mill, resulting in the accumulation of sediments and the establishment of mangrove environments in what were degraded areas. [ABSTRACT FROM AUTHOR]

Surface elevation tables (SETs) estimate the vertical resilience of coastal wetlands to sea-level rise (SLR) and other stressors but are limited in their spatial coverage. Conversely, spatially integrative metrics based on remote sensing provide comprehensive spatial coverage of horizontal processes but cannot track elevation trajectory at high resolution. Here, we present a critical advance in reconciling vertical and horizontal dynamics by assessing the relationship between elevation change, relative tidal elevation (Z*), and the unvegetated-vegetated marsh ratio (UVVR) across coastal wetland complexes in the southeastern USA. We first used the UVVR to determine the representativeness of the SET site relative to varying spatial footprints across the complex and found that SET sites generally represent the tidal wetland areas in terms of vegetated cover. There is also overall coherence between positive vertical change and high vegetative cover, but we also identified sites with high vegetative cover and negative vertical change (relative to SLR). The only sites exceeding the pace of SLR have UVVR values below the previously established 0.15 threshold. Some sites are not keeping up with SLR despite having intact marsh plains; this may indicate a risk of submergence with undetectable marsh plain loss, or an imminent transition to future open-water conversion. Aggregation of Z* across the same footprint as the UVVR demonstrates consistent coherence between elevation and vegetative cover, with lower elevation sites having larger UVVR. These results indicate that the UVVR is a suitable initial screening tool: areas above the 0.15 threshold are both horizontally and vertically vulnerable. Furthermore, this comparison suggests that horizontal integrity is a prerequisite for vertical stability: a marsh can only maintain elevation if the plain is intact with minimal unvegetated area. [ABSTRACT FROM AUTHOR]

ABSTRACT Precipitation is the fundamental source for various research areas, including hydrology, climatology, geomorphology, and ecology, serving essential roles in modelling, distribution, and process analysis. However, the accuracy and precision of spatially distributed precipitation estimates is a critical issue, particularly for daily scale and topographically complex areas. Although many datasets have been developed based on different algorithms and sources are developed for this purpose, determining which of these datasets best reflects actual conditions is quite challenging. This study, hence, aims to compare the 25 global distributed precipitation estimates (gridded, satellite, model, and fused) concerning 221 ground‐based observations based on the ranking of 18 continuous (evaluation statistics), eight categorical (precipitation indices), and two seasonality metric (high and low precipitation). Upon examining the results, gridded and model precipitation data including APHRODITE (Asian Precipitation—Highly‐Resolved Observational Data Integration Towards Evaluation), CPC (Global Unified Gauge‐Based Analysis of Daily Precipitation), ERA5‐Land (ECMWF Reanalysis 5th Generation for Lands), and CFSR (Climate Forecast System Reanalysis) occupy the top four positions in continuous metrics. In contrast, satellite data such as PERSIANN‐PDIR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks), CMORPH (Climate Prediction Center morphing method), IMERG (The Integrated Multi‐Satellite Retrievals for GPM), and TRMM‐TMPA (Tropical Rainfall Measuring Mission/Multi‐satellite Precipitation Analysis) dominate in the top four positions in categorical metrics. For seasonality of high and low precipitation, fused, gridded, and reanalyses products such as CPC, MSWEP (Multi‐Source Weighted‐Ensemble Precipitation, version 2), HydroGFD (Hydrological Global Forcing Data), CFSR rank among top four. Based on the first five rankings of all metrics, fused (multiple sourced) and gridded datasets accurately reflect the actual situations compared to other precipitation products. Reanalysis (model) and satellite‐based follow this rank, respectively. The results clearly indicate that fused precipitation derived products from multiple sources offer better accuracy and precision in representing the spatial distribution of precipitation on a daily scale. [ABSTRACT FROM AUTHOR]

The article in Scientific Reports discusses a tectonic study of the Magallanes Fault System in Tierra del Fuego, Patagonia, focusing on fault slip rates. The study challenges the robustness of the dating and suitability of geomorphic markers used by previous researchers. The authors caution against drawing conclusions based on unsuitable markers and cropped images, emphasizing the need for rigorous investigation in tectonic geomorphology. The article highlights discrepancies in dating and offset measurements, urging for a more comprehensive and accurate approach to understanding fault slip rates in the region. [Extracted from the article]

This article explores the luminous exchanges that animate contemporary Western geoscience ways of imagining the Earth. Inquiring into fluvial geomorphology, it employs creative research practice and feminist materialist ideas to interrogate the multiple roles of light in the ways in which rivers become configured, envisioned, and known. Focusing on the River Torne in northern Finland and Sweden, the article contemplates creative gestures of sensing the Torne via various “technologies of light,” which draw the researcher into a haunted, intra-active, and ecological exchange with the riverscape. This immersive engagement with the Torne prompts reflection on the particular riverine knowledges, ecologies, and archives that become presenced in luminous research encounters—prompting a recognition of a distributed cognition in our practices of knowing riverscapes. In the process, the geomorphological notion of a riverscape archive becomes situated amid complex ecologies of light, which invites a radical commitment to the memory and lively potentiality of place and encourages care-full research entanglements within our luminous research archives. [ABSTRACT FROM AUTHOR]

AbstractAs the domain of artificial intelligence has advanced, the integration of deep learning techniques into terrain and landform analysis has become more prevalent. Nevertheless, many existing methods are fully supervised and designed for specific tasks; thus, their transferability is limited and massive annotated samples are required. This study introduces a geomorphic pretrained model (GeomorPM) capable of performing multiple tasks. First, an architecture was designed that combined a convolution-based Vector Quantised-Variational Autoencoder (VQVAE) with a Transformer-based masked autoencoder (MAE) framework, allowing it to autonomously learn local details and global patterns from large-scale digital elevation model (DEM) data. Subsequently, GeomorPM, based on the VQMAE architecture, was pretrained on massive DEM data and fine-tuned for three specific tasks: DEM void filling, DEM superresolution, and landform classification. GeomorPM outperformed the traditional and other deep learning methods in all three tasks, demonstrating the superior learning ability and transferability of the model. This study provides a practical framework for developing pretrained models based on DEMs that can be expanded to other continuous geoscientific data. [ABSTRACT FROM AUTHOR]

Quantitative landslide hazard models provide estimations of the number of landslides per area and time that might be expected in the near future. These models are essential to calculate landslide risk in monetary terms. Although they are very useful tools for managing the activity of unstable slopes, their production calls for a vast amount of spatial and temporal data. Here, we present a case where this was possible producing the quantitative landslide hazard map for the municipality of Loja, Ecuador. It is based on a model that integrates six causal factors (distance to faults, lithology, slope, geomorphology, topographic position index, land use) and a comprehensive multi-temporal inventory of landslides. First, a susceptibility map was generated with a good prediction capability (Area under prediction rate curve, AUPRC: 0.8) combining two widely used and tested probabilistic methods: "Matrix" and "Likelihood ratio". Subsequently, this map was transformed into a hazard map by including the temporal frequency of landslides. The map assesses the annual probability of each pixel to be set in motion within one of these landslides. The preliminary temporal validation of the hazard map indicates that the pixels mobilized during two years after the map production fit reasonably well with our spatio-temporal forecast. The findings emphasize that classical spatial prediction methods, when augmented by robust and extensive data on landslide distribution and activity, can yield hazard models with reliable predictive capabilities. This suggests that in practical applications, models based on relatively simple calculations can provide effective and reliable starting points for managing landslide risks. [ABSTRACT FROM AUTHOR]

A synthesis of field geological and archaeological surveying, as well as near-surface stratigraphy, provides new insights into the late Quaternary history of this region. We find a long series of alluvial, colluvial, playa, and aeolian deposits that show a complicated history of changes in the late Quaternary climate and environment. In the current study, we summarize the results of a geoarchaeological study that focused on the entire range of landscapes and associated landforms along the fringe of the Libyan Plateau at Umm Dabadib, Kharga Oasis, in the Western Desert of Egypt. We also determined the distribution of the cultural materials of prehistoric sites in different geomorphic settings, including playas, wadis, and dune fields. [ABSTRACT FROM AUTHOR]

Morphometric analysis of previously unresearched tributary junction fans (TJFs) of the Spiti valley cold desert, India, was conducted to understand the factors influencing their development. An integrated remote sensing and field approach was employed, including the development of multi-method morphometric indices viz. fan conicality (FCI), sweep angle (SA), fan width-to-length ratio (W/L), feeder stream-order and valley floor width-to-height ratio (Vf). Such TJFs, which are the most suitable cultivation and settlement sites in this region, were found to be largely polygenic and planimetrically confined, with many being multi-staged in terms of their development. The results of morphometric analyses reveal that the TJFs are relatively smaller but steeper than their counterparts in other settings, with high relative topographic confinement causing the construction of smaller and steeper fans. The competence of the feeder stream, along with associated processes, notably influences fan morphology using differential sediment transporting capacity. TJFs created by more competent streams are less steep, more influenced by topographic confinement and more vulnerable to truncation by the trunk stream. Furthermore, tectonically induced base-level fall and resultant downcutting in confined environments have caused the formation of truncated, multi-staged and entrenched fans and are primarily responsible for coupling between TJF catchments and trunk stream in the study area. [ABSTRACT FROM AUTHOR]

One of the legacies of the Apollo missions and the fleet of unmanned probes that have followed them is the recognition that the Moon is far more active than previously believed, with seismic activity deep in the lunar interior and some tectonic activity at shallower depths, as well as gas release from below the surface. Here, we review lunar activity in the context of reports of the observation of transient lunar phenomena (TLPs), attempting to separate myth from reality. We suggest that a significant fraction of reported TLPs could have an explanation in local geology or geomorphology. In a further paper we will examine one particularly well-known TLP report to see if there is a plausible explanation based on local geology. [ABSTRACT FROM AUTHOR]

Terrain analysis plays an important role in computer graphics, hydrology and geomorphology. In particular, analyzing the path of material flow over a terrain with consideration of local depressions is a precursor to many further tasks in erosion, river formation, and plant ecosystem simulation. For example, fluvial erosion simulation used in terrain modeling computes water discharge to repeatedly locate erosion channels for soil removal and transport. Despite its significance, traditional methods face performance constraints, limiting their broader applicability. In this paper, we propose a novel GPU flow routing algorithm that computes the water discharge in 풪(log n) iterations for a terrain with n vertices (assuming n processors). We also provide a depression routing algorithm to route the water out of local minima formed by depressions in the terrain, which converges in 풪(log2 n) iterations. Our implementation of these algorithms leads to a 5× speedup for flow routing and 34 × to 52 × speedup for depression routing compared to previous work on a 10242 terrain, enabling interactive control of terrain simulation. [ABSTRACT FROM AUTHOR]

Coastal hazards threaten properties, infrastructure, and cultural sites around Aotearoa New Zealand's (hereafter Aotearoa) coastline and sea-level rise (SLR) will escalate this problem. At present it is unclear how archaeological sites will be affected by future coastal erosion and inundation. In this paper we combine national-scale archaeological and environmental datasets to provide a first-pass overview of archaeological heritage at risk in Aotearoa. Two key national-scale datasets are utilized: (1) coastal sensitivity index (CSI) developed by the National Institute of Water and Atmospheric Research; and (2) ArchSite, Aotearoa's archaeological site database. The integrated datasets produce insights into the sensitivity of coastal archaeology to SLR and associated hazards, which are vital to planning for the loss of coastal archaeological sites. More than half (∼55%) of recorded coastal archaeological sites around Aotearoa are midden (n = 4938) and about 25% (n = 2271) are earthworks. In total, ca. 12% (9054) of all known archaeological sites are within 1000 m of soft shore shorelines. Of this total, only about 3% (302) of sites are burials, but the loss of these 302 burial sites would have very high cultural impact. Coastal erosion is a particularly important threat to archaeology as it would permanently remove sites, whereas the risk of site removal by coastal flooding inundation is lower. Our results show that about 22% (1954) of coastal archaeological sites are located on landforms that are sensitive to SLR-driven erosion: 29% (2660) of archaeological sites are located on foredune barrier beaches, 23% (2059) on foredune barrier plains, 14% (1283) on beaches, and 9% (808) on beach ridge barriers. This work draws attention to the scale of coastal archaeology in Aotearoa that needs adequate documentation, preservation, and potentially protection in the face of SLR. Robust coastal erosion and inundation datasets are needed to more deeply understand potential SLR-driven impacts on coastal archaeology and provide a scientific foundation for considering future adaptation options. [ABSTRACT FROM AUTHOR]

A systematic interdisciplinary approach based on the socio-ecological model of the Vienna school has been adopted to achieve a more nuanced and multifaceted understanding of the ancient metropolis of Pergamon (western Anatolia) and its micro-region. The city of Pergamon ranks among the 'guiding fossils' of urban culture in antiquity. We describe how the socio-ecological model is subject to adaptation and discussion to fit the needs and circumstances of archaeology. In focussing on geomorphodynamics, we use several approaches to conceptualise and model selected aspects of human-environment interactions, integrating data from physical geography, archaeology, building archaeology (Bauforschung) and ancient history. The model includes several dimensions of the social metabolism of Pergamon, first and foremost the carrying capacity of the environment and demographics, comprising population increase and labour as an active investment in nature. Geomorphodynamics are regarded as major 'events' in the model, related to the social metabolism (e.g. increased erosion/deposition in the micro-region in relation to urban sprawl). With the social-ecological model, it is possible – and becomes imperative – to include the perception and representation of human-environment interactions manifested in, for example, administrative patterns and religious practices or architecture and built infrastructure (such as terraces, riverbank stabilisation, substraction terraces and substraction bridges). Geomorphodynamics also involve various aspects of the perception of the environment, though these are not recorded in ancient texts on Pergamon known to date. Concurrently, the importance of the model in organising, structuring, and communicating interdisciplinary collaboration and discourse is highlighted. [ABSTRACT FROM AUTHOR]

Monitoring of compensatory stream mitigation projects conventionally relies on spatially discrete geometric data and habitat assessments collected from representative reaches. Project success is evaluated by extrapolating site‐scale metrics such as rapid bioassessment protocol (RBP) scores and time‐series changes in width‐to‐depth ratios to adjacent reaches. For example, an excellent RBP score at one location is used to infer excellent habitat in nearby reaches. This paper compares spatially discrete and continuous monitoring data from 38 km of restored stream length on a stream mitigation project in central Kentucky to document how conventional site‐level metrics may not represent conditions in adjacent reaches, particularly on projects plagued by post‐construction geomorphic instability (e.g., headcut migration, propagation of bank erosion, and chute cutoff formation). Over a 5‐year monitoring period, rapid visual assessment walkabouts documented project‐scale geomorphic process trajectories that were not captured by conventional site‐specific monitoring. Early detection of geomorphic instability from this rapid monitoring approach facilitated cost‐effective and tailored adaptive management (e.g., planting of live stakes to arrest bank erosion). Full‐census walkabouts can thereby help to improve mitigation credit valuation, enhance long‐term habitat protection, and facilitate successful steam restoration outcomes. [ABSTRACT FROM AUTHOR]

Fluvial networks are characterised by spatial and temporal transitions as geomorphic and ecological processes within these systems are mediated longitudinally by sediment and water fluxes which vary spatially in magnitude and variability. The aim of this special issue was to shed light on the nature of source-to-sink fluvial transitions associated with spatial and temporal variability in geomorphic and hydrological processes. We encouraged contributions that considered fluvial transitions at any spatial or temporal scale, and invited research that addressed the implications of such transitions. The number of submissions was limited, which was potentially indicative of the lack of field-based studies being conducted at a catchment- or source-to-sink scale. Two of the published submissions considered longitudinal transitions in sediment sources using a sediment finger-printing approach, while the remaining two articles combined traditional fluvial sedimentology techniques with optically stimulated luminescence chronology to deduce controls on river reach flood dynamics. As we enter a time of unprecedented human impact on the environment, there is a clear need for future research to focus on the catchment as a holistic unit as the interconnectedness of landscape pattern and process has implications for biodiversity, water quality, ecosystem service provision and thus catchment management. [ABSTRACT FROM AUTHOR]

The Letaba River is one of several east-flowing rivers in the semiarid region of northeast South Africa. There is strong seasonality of river discharge and patterns of geomorphic behaviour along bedrock- and sediment-dominated reaches in these rivers, and in response to extreme seasonal flood events. This paper presents new luminescence ages on sediment samples from five sites in upper (headwater) reaches of the Letaba River catchment outside of Kruger National Park, South Africa, combined with evidence from reach-scale geomorphology and sediment sample analysis. River reaches are mainly mixed bedrock-alluvial with a patchwork of poorly sorted coarse sand bars overlying an abraded extended bedrock channel system. Luminescence ages from river sediment deposits (n = 13) cluster around three time periods of the last 400 years, 500–1100 BP, and 1400 BP. This suggests different reworked populations are present, which are a result of the partial bleaching of quartz grains and, thus, a mixed luminescence signal as flood-transported sediments are progressively moved from one depositional sink to another. This pattern of luminescence ages is quite different to lowland river systems in the same region where ages on the whole are significantly younger. Flood processes and dynamics in headwater reaches of semiarid rivers are often not considered but can yield a better understanding of system sensitivity to climate and event forcing. [ABSTRACT FROM AUTHOR]

Jimibong is a north-facing horseshoe-shaped scoria cone in the northeast of Jeju Island that released lava flows to form a semicircular lava plateau. Sixty volcanic hummocks comprising scoria, spatter, and volcanic bombs are found on the lava plateau. The hummocks can be classified into Type 1 and Type 2 according to clast components, distance from the vent, and internal structure. Type 1 hummocks, distributed within approximately 1,000 m of the vent, comprise scoria deposits mixed with volcanic bombs and relatively few dykes that rise from the underlying lava. In contrast, Type 2 hummocks, distributed 1,000–1,300 m from the vent along the coast, comprise spatter/scoria and volcanic bomb deposits. The spatter/scoria of the Type 2 hummocks is highly agglutinated with abundant squeezing dykes that originated from the underlying lava and locally extruded over the hummocks. Although both the Type 1 and Type 2 hummocks comprise parts of the collapsed and rafted spatter/scoria blocks, their differences in shape, clast components, and structures are explained by changes in the eruption style (from spatter to scoria) and rheological changes in the lava with distance from the vent. Lava flows breached the cone following spatter-dominated eruptions in the early stages of Hawaiian eruption. Through this partial cone collapse, spatter blocks were transported with the lava flow away from the cone. The lava surface then cooled and hardened as the lava temperature decreased and viscosity increased. The contraction of the lava due to cooling caused the rafted cones to fragment into various sizes as they cracked, fractured, and rotated. Hot liquid lava from within the flow was squeezed-up because of the volcanic load of the rafted blocks, intruding into the fractures in the rafted blocks before locally flowing over them, creating the characteristic Type 2 hummocks. In contrast, Type 1 hummocks formed in the later stages of Strombolian activity, when scoria-dominant eruptions caused collapsed scoria blocks to be rafted with the lava flow. These scoria blocks were deposited in areas proximal to the cone and show few dyke intrusions due to the limiting effects of edifice load on dyke development. The Jimibong volcano provides an example of changing hummock structures in relation to changing eruption styles of scoria cones, deepening our understanding of the geomorphic development in volcanic regions. [ABSTRACT FROM AUTHOR]

Alluvial rivers are dynamic landscapes on the earth's surface that evolve with time. While many studies have examined the immediate effects of floods on river channels, there is a lack of research that investigates the longer-term evolution of river morphology following such events. The present study was carried out on the Upper Krishna River which flows between the southern part of Maharashtra and the northern part of Karnataka states in India for 375 Km. The morphological parameters were analyzed for three decades (1991–2021) and the year 2019 with the highest flood level was also considered for change analysis. The assessment was done for change in active channel area, mean width, bank line migration, sinuosity index, and erosion-accretion. The land use classification was also analyzed for the study period to understand the exposure to future floods. The spatial data was retrieved from different satellite missions and analyzed with the help of Remote Sensing (RS) and Geographical Information System (GIS). The river was divided into seven segments (R1, R2, R3, R4, R5, R6, and R7) and bank lines were digitised manually to minimise possible errors. The results show that during the study period, the river channel has been modified in terms of active channel area expansion in the R1, R5, R6, and R7, and erosion was found the dominating process while the left bank was more erosive than the right bank of the river. The built-up area was seen going through a major expansion than any other land use class. The discharge and sediment data confirm the flood years (1994, 2005, 2006, and 2019) which accelerated the morphological activity in the river segment. The results of the study provide new insights related to short-term morphological changes in the Upper Krishna River and can be used by policymakers and managers to carry out future development plans and river training work at affected sites. [ABSTRACT FROM AUTHOR]

The increasing use of drone technology to produce high-resolution digital imagery and elevation models has been associated with a growing interest in developing quantitative morphometric analysis (QMA). QMA analysis is an invaluable part of creating detailed topographic models in landslide scars that are still highly unstable and prone to erosion. This paper presents the results of a research that aims to create a topographic model in a landslide scarred area where the slope configuration is still varied. The study area was located in the landscape of the Cretaceous-Tertiary volcanic transition where many landslides have occurred. Three landslides were selected on the basis of different soil material characteristics that affect the topographic condition of the landslide scar. Aerial photography was recorded using a UAV with a flying height of 80 m, with an orthomosaic resolution of 1 cm. In detail, three morphometric variables (slope, plan curvature, topographic position index) were selected and calculated with the output evaluated based on visual-spatial interpretation. The results showed that morphometric variables performed well in modeling land surface topography. Steep slopes and surfaces with convex curvature are abundant at the ledges and landslide heads that allow water runoff to disperse as the initiation of gully erosion. The multidimensional gully erosion network is concentrated at relatively low elevations and surfaces with concave curvature. The undulating micro-relief of the land surface as a result of the process of material disposition builds up on each other to a gentle slope. Finally, the topographic model of the landslide surface can be used as a base material in implementation of both physical and vegetative land conservation strategies. [ABSTRACT FROM AUTHOR]

Downstream pebble variability in river systems is assessed through various methods, with recent emphasis on efficient, time-saving semi-automatic processes involving photography and digital analysis. The Inaouène valley, however, lacked a comprehensive survey of its main channel using either manual or image-based methods. This study bridges this gap by combining both approaches to analyze the downstream evolution of surface pebbles' morphometric parameters along approximately 60 km of the Inaouène's middle reach. Our research focuses on two key aspects: grain size and particle shape. Results reveal a general downstream trend of size fining, increasing circularity and decreasing elongation, primarily attributed to abrasion and travel distance. Notably, this pattern is interrupted by localized variations associated with tributary inputs and sediment recycling processes. This study significantly contributes to the understanding of fluvial sediment dynamics in the Inaouène Valley. Its findings have broad implications, supporting ecological assessment and restoration efforts, while also informing decision-making in river engineering and management. By providing a comprehensive analysis of pebble characteristics and their downstream evolution, this research establishes a foundation for future geomorphological studies and practical applications in river system management. [ABSTRACT FROM AUTHOR]

River deltas are ecologically critical landscape components and are responsible as habitats for millions of people, wildlife, and plant communities. Deltas store vast quantities of eroded nutrient‐rich sediment and play a significant role in water quality management through nutrient cycling and storage. Many studies have been conducted in marine and tidal delta environments that characterize the sedimentology and geomorphic characteristics of these relatively young landscapes. However, little work has been completed in even younger inland reservoir deltas. This study characterized the sediments and geomorphology of the growing delta forming at the outlet of the Des Moines River into Red Rock Reservoir in south‐central Iowa and discussed the implications of the lower delta sediment and topographic characteristics in terms of sediment and nutrient storage, and the potential impact of the delta on other hydroecological factors. We found that the ca. 30‐year‐old lower delta is storing up to 60% of the contributing watershed's eroded sediment and total carbon, with total sediment depths of ca. 9 m across the 755‐ha area. Further, we identified two major geomorphic landscape positions within the lower delta that were categorized as distributary channels and delta plains. Sedimentological differences in these microscale landscape positions were identified. Sand content was greater at lowest distributary channel elevations and at the highest plain elevations whereas silt dominated the elevation range between these two extremes. The zone of silt accumulation corresponds to the range in elevation associated with normal lake level management. The silt‐dominated area is regularly inundated and covered with a variety of emergent vegetation and is the zone of critical importance for waterbird habitat and nutrient‐processing capacity. [ABSTRACT FROM AUTHOR]

This paper reviews the history of the International Association of Geomorphologists (IAG), an organization formally established in 1989, but with the foundations laid at the First International Conference on Geomorphology in Manchester in 1985. It recreates the spirit of the 1980s, when the need for more efficient international cooperation on an equal basis was argued for, and outlines steps which led to its setting up. The model of operation of the IAG is presented, emphasizing membership by countries, followed by milestone institutional developments, listing of IAG officers and its Honorary Fellows. Key IAG activities are conferences, projects run by working groups, training and support programmes for early career geomorphologists, and publications. A summary of major achievements and challenges for the future concludes the paper. [ABSTRACT FROM AUTHOR]

Geomorphological evolution is one of the main factors that increases flood damage in small or medium rivers located in upstream river reaches. These types of flood damage have been increasing at knickpoints where the riverbed slope and river width change abruptly and are likely to cause non‐equilibrium conditions for sediment transport during floods. Therefore, it is important to understand the non‐equilibrium morphological response at the knickpoint and the resulting new dynamic equilibrium state under given external forces. The effects of two‐dimensional (2D) morphological features on the dynamic equilibrium riverbed profile, however, have not been specifically studied because the methods currently in use for calculating equilibrium profiles are based on zero‐ or one‐dimensional (0D or 1D) modeling. Here, we perform numerical calculations using the 2D morphodynamic model iRIC‐Nays2DH to clarify the dynamic equilibrium profile and the process of reaching a dynamic equilibrium state. We also use an existing 1D model to show the 2D effect in the dynamic equilibrium state. To understand this, we set up three channels: slope transition point, width transition point, and both the slope and width transition point. 1D results show a constant slope profile in channels with constant width and upward‐convex profiles in channels with width expansion at the equilibrium state, owing to the adjustment of the difference in sediment transport volume in the two reaches with different widths by changing the slopes. In contrast, the 2D results show that the alternate bars create a small autogenic knickpoint even in the straight channel and significantly dampen sediment deposition at the width expansion point, as seen in the 1D model result. This was because the bars' shape increased the volume of sediment transport because the shape of the bars concentrated flow. These results suggest that 2D morphological features, such as fluvial bars, play a significant role in the equilibrium riverbed profile. [ABSTRACT FROM AUTHOR]