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Arctic amplification of climate change has resulted in increased coastal hazards impacts to remote rural coastal communities in Alaska where conducting research can be difficult, requiring alternate methods for measuring change. The pilot program, Stakes for Stakeholders, was initially planned to be funded from 2016–2018. Upon project completion the work has shifted to individual community's partnering with several agencies to continue the work. This research showcases a successful long-term community-based erosion monitoring program in two rural communities in Southwest Alaska. The resulting outputs from the workflow we developed were (1) locally prioritized data products, such as a hazard assessment report for Chignik Bay and (2) evaluation rubrics used to assess the suitability of future sites and the efficacy of the program. Our model of two-way communication, responsiveness to individual community needs, and attention to efficiency and effectiveness of the program workflow, can serve as a model for universities, for-profit, non-profit, Tribal, city, state, and federal research agencies and communities partnering to respond to global climate change. [ABSTRACT FROM AUTHOR]

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]

As 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]

This Editorial paper summarizes the Special Issue entitled "Evolution of Soil and Water Erosion" in Water. This Special Issue aims to collect new knowledge on and advances in the evolution of soil and water erosion and its complex interplay with natural and human-induced factors. Five high-quality papers have been published in the Special Issue, which mainly covers new insights into the themes of erosion mechanisms and environmental drivers, erosion control and mitigation strategies and the relationship between hydraulic parameters and erosion. Overall, these studies have broadened the understanding of soil erosion and soil and water conservation, emphasizing the importance of research in this field for environmental sustainability. In future research, interdisciplinary integration into theory and methodology will play a crucial role in breakthroughs in the understanding of soil erosion and innovations in prevention and control technologies. [ABSTRACT FROM AUTHOR]

Monitoring active seafloor processes requires repeated, comparable surveys to enable change detection. The change detection of the deep ocean floor, however, is rare due to a paucity of repeat data at an appropriate resolution. In this study, we use an exceptional suite of bathymetric surveys across a spatiotemporal range at the submarine Havre volcano, Kermadec arc, Southwest Pacific, to investigate geomorphic change over 13 years (2002, 2012, and 2015). The integration of bathymetric observations with remotely operated vehicle (ROV) observations and sampling data refined geomorphic boundaries, and four geomorphic groups at varying scales are interpreted: (i) large-scale tectonic and volcanic features, e.g., faults and calderas; (ii) coherent volcanic products, e.g., lavas; (iii) clastic primary volcanic products, e.g., giant pumice deposits; and (iv) mass-wasting features and products, e.g., landslide scarps. Three 25-m resolution geomorphic maps for broad-scale feature change and high-resolution 1-m autonomous underwater vehicle (AUV) bathymetry are used to develop a fine-scale geomorphic map that reveals additional landforms and processes. We integrate bathymetric data with sampling data and ROV video footage of the seafloor to refine geomorphic boundaries. We also integrate the results of previous geological studies of Havre to inform the geomorphic interpretation. Our map reveals a variety of geomorphic forms from a range of volcanic and mass-wasting processes that aid in the interpretation of the growth and evolution of submarine volcanoes. One new observation reveals a significantly larger scale of cryptodome emplacement than recognized previously recognized, accounting for an additional volume of 0.0055 km3 to the 2012 eruption products. This emplacement took place along two linear southern caldera ring faults and likely continued after the formation of the giant pumice raft on 18 July 2012. A key result is the extension of the timeline for the emplacement of volcanic products associated with the 2012 eruption, revealing an additional volume growth of 0.001 km3 on the primary dome (dome OP) between 2012 and 2015. This additional emplacement is documented in this study for the first time and extends the known volcanic emplacement timeline from 3 months to a maximum of 3 years. Our work reveals seafloor modification continuing long after an observed volcanic eruption event as lingering lava emplacement and mass wasting remobilize newly erupted and older products that comprise the edifice. [ABSTRACT FROM AUTHOR]

Introduction: Remotely-sensed acoustic backscatter is an indispensable tool for seabed mapping, among other disciplines. Almost a decade after the GeoHab Backscatter Working Group published its guidelines and recommendations report, new technologies, new challenges and new questions have emerged. Given the range of potential backscatter research avenues, it can be difficult to align research programs with the priorities of the community of practice. Prioritization of backscatter research topics is thus necessary to establish a roadmap for acoustic backscatter research efforts. Methods: We asked the international community working with acoustic backscatter to submit their priority research questions over a 5- to 10-year horizon. We analyzed and curated a total of 177 research questions from 73 contributors, and the resulting 104 questions were grouped into eight broad recurring themes: "Technologies", "Calibration", "Data acquisition and ground-truthing", "Data processing", "Post-processing, quality control, data handling, and curation", "Data analysis", "Data interpretation", and "Applications and end uses". A follow-up survey based on the final list of questions was distributed to characterize the community working with backscatter and to identify key research priorities. Results: A total of 120 responses originating from 23 countries were used for the analyses. Most respondents were researchers (68%), while others were technicians (25%) or department or program managers (11%), among other roles. Affiliations of respondents included academia (43%), governmental agencies (37%), and industry/private sector (18%). After scaling the responses, the most commonly selected theme was "Post-processing, quality control, data handling, and curation", followed by "Calibration" and "Data analysis". Respondents consistently ranked several research questions as priorities. The two questions that were identified as priorities by over 25% of respondents were "How can we move towards absolute calibration of different systems to allow interregional comparisons?", and "How can we quantify seafloor backscatter quality and develop standards similar to what exists with bathymetry?". Discussion: All eight themes are represented in the top 10 priority questions, underscoring the need for contributions to backscatter research from multiple perspectives to advance the field. The ranking of priority questions encourages collaboration within the community and will serve as a roadmap for backscatter research programs over the next decade. [ABSTRACT FROM AUTHOR]

The dune density is an important parameter for representing the characteristics of desert geomorphology, providing a precise depiction of the undulating topography of the desert. Owing to the limitations of estimation methods and data availability, accurately quantifying dune density has posed a significant challenge; in response to this issue, we propose an innovative model to estimate dune density using a dune vertex search combined with four-directional orographic spectral decomposition. This study reveals several key insights: (1) Taklimakan Desert distributes approximately 5.31 × 107 dunes, with a linear regression fit R2 of 0.79 between the estimated and observed values. The average absolute error and root mean square error are calculated as 25.61 n/km2 and 30.48 n/km2, respectively. (2) The distribution of dune density across the eastern, northeastern, southern, and western parts of the Taklimakan Desert is relatively lower, while there is higher dune density in the central and northern areas. (3) The observation data constructed using the improved YOLOv8s algorithm and remote sensing imagery effectively validate the estimation results of dune density. The new algorithm demonstrates a high level of accuracy in estimating sand dune density, thereby providing crucial parameters for sub-grid orographic parameterization in desert regions. Additionally, its application potential in dust modeling appears promising. [ABSTRACT FROM AUTHOR]

Offshore Nile Delta in Egypt represents an enormous hydrocarbon province with recent projected gas and condensate discoveries of more than 50 trillion cubic feet "TCF". Most of these occur in the post-salt hydrocarbon plays where biogenic gases are dominant. This study integrates organic geochemistry, seismic geomorphology and petrophysics in order to decipher the origin, and accumulation conditions of the wet gas/condensate blend in the Upper Miocene sub-salt Wakar Formation sandstones in Port Fouad Marine "PFM" Field, offshore Nile Delta. Hydrocarbon pay zones are scattered thin (<10 m) sandstones deposited in as turbiditic channel/levee complex facies. Spatial distribution of vertical gas chimneys (~2 km wide) rooting-down to the Messinian Rosetta salt is associated with the lateral pinching-out of the turbiditic sandstones. Organically-rich (total organic carbon "TOC" > 1 w.t.%, hydrogen index "HI" > 200 mgHC/gTOC) and mature (Tmax > 430 °C, vitrinite reflectance "VR" > 0.6 %Ro), source rocks are restricted to Upper Miocene Wakar and Oligo-Miocene Tineh formations. The latter contains more mature organofacies (up to 1.2 %Ro) and type II/III kerogen, thereby demonstrating a good capability to generate wet gases. The studied gas is wet and has thermogenic origin with signs of secondary microbial alteration, whereas the condensate contains a mixture of marine and terrestrial input. Molecular biomarkers of the condensate, isotopic and molecular composition of the gas reveals a generation of condensate prior to gas expulsion from the source. The Wakar sandstones have a heterogeneous pore system where three reservoir rock types (RRTI, RRTII and RRTIII). RRTI rocks present the bulk composition of the Wakar pay zones. Spatial distribution of RRTI facies likely control the accumulation of the sub-salt hydrocarbons. Our results provide a new evidence on an active petroleum system in the sub-salt Paleogene successions in the offshore Nile Delta where concomitant generation of gas/condensate blend has been outlined. [ABSTRACT FROM AUTHOR]

Over the past decade, the Southwest coast of Sri Lanka has experienced recurrent coastal floods, particularly in the stretch from Akurala to Godagama. This study, spanning from 2010 to 2020, seeks to unravel the factors influencing these floods, filling a void in existing research on the subject. Employing topographic maps, field observations, and bathymetric data from the Lanka Hydraulic Institute and Coastal Conservation Department, the research delves into geomorphological features and elevation variations in the study area. Findings indicate that high elevation in the Ambalangoda to Akurala and Godagama to Hikkaduwa regions contributes to coastal flooding, as these areas are elevated above the mean sea level. The bathymetric analysis exposes closely spaced contours and steep slopes, exacerbating flooding when waves collide with the coastline. The absence of mangroves amplifies the impact, distinguishing the study area from its neighbouring regions. Socioeconomic consequences include road closures, accidents on the Galle-Colombo main road in 2020, and adverse effects on fisheries and tourism. Environmental impacts encompass coastal erosion, degraded water quality, coral bleaching, and saltwater intrusion. While artificial structures like rock barriers mitigate flooding, the study underscores the interplay of land morphology, bathymetry, land use, and climate influencing coastal flooding along the Akurala to Godagama coast. [ABSTRACT FROM AUTHOR]

The common thread of this geographical itinerary through the Peña Ubiña Massif is the modeling forms and the landscape in a high Cantabrian Mountain area. From eight stops in enclaves of special geomorphological relevance, the morphological traces of the Last Glaciation, periglacial processes, snow forms, karst modeling, fluviotorrential action and the vestiges of anthropic activity and the Spanish Civil War are observed. The aim is to revalue the geomorphological heritage, a fundamental element in the management plans of protected natural spaces that increasingly demands more efforts for its dissemination. [ABSTRACT FROM AUTHOR]

The Lucanian site of Laurelli represents one of the largest, still poorly investigated, pre-Roman archaeological sites of the Cilento, Vallo di Diano and Alburni Geopark (southern Italy). The site lies on a large, low-relief surface in the upper portion of the Serrapotamo River basin, a right tributary of the Bussento River. Geomorphological, stratigraphical, archaeobotanical and archaeometric analyses were carried out to understand the following: (1) the choice to settle at the site of the town of Laurelli; (2) the origin of the raw material used to build the town; (3) the vegetation present during the lifetime of the town; and (4) the causes of its abandonment. The results indicate that the site was chosen because it was almost stable from a geomorphological point of view, not being affected by deep landslides. Further investigations are needed to unravel the possible occurrence of flooding as a causative event for the abandonment of Laurelli. Carpinus was widespread and used as a fuel for iron production, but the areas from which the iron was extracted have not yet been discovered. The multidisciplinary approach adopted is suitable for application in other archaeological areas worldwide. [ABSTRACT FROM AUTHOR]

Aeromagnetic data over parts of the Northern Anambra and Southern Bida basins have been evaluated with emphasis on the subsurface geologic structures controlling mineralization and delineating the geomorphology of the basin. Four aeromagnetic data sheets (246 (Kabba), 247 (Lokoja), 266 (Auchi), and 267 (Idah)) were acquired through purchase, assemblage, analysis, and interpretation using integrated processing techniques of Euler deconvolution, analytical signal (AS), source parameter imaging (SPI), and 3D magnetic inversion model. The data are collected laterally in a series of NW-SE trajectories spaced 2 km apart, with an average flight altitude of approximately 150 m, and tielines occurring at approximately 20 km intervals. Qualitative observation of TMI and RAM shows that the research region is greatly fractured, with structures orienting in the E-W direction. The spectral analysis result shows that the sedimentary infillings range from 0.60 to 4.03 km. 3D model and curie isotherm depth subsurface maps reveal deeper curie depths at Kabba, Adavi, and Itakpe zones (28.0-40.0 km) and shallow curie depths at Auchi, Osara, Idah, and Anyigba areas (18.0-27.0 km). The result from the heat flow model shows an inverse relationship with the Curie isotherm depth. The contact depth sources calculated from Euler depth assessments show that the majority of these contact sources are trending in the E-W directions. The overall structural geomorphology of the research region conforms to the general pattern of structural trends within the research region. Most of the structures are trending NNE-SSW, NNW-SSE, and NESW, while the minor structures trend in the E-W direction. 3D inversion results show a discrete subsurface geologic structure that may house minerals within the region. [ABSTRACT FROM AUTHOR]

Fish assemblages, defined by taxonomy or functional traits, –respond to regional and local habitat variation. Our hypothesis was that fish assemblages could be best predicted using reach‐scale (RS) hydrology variables over valley‐scale (VS) hydrogeomorphology variables for US and Mongolian rivers. We further predicted that fish traits were predicted better by RS than VS variables. We evaluated the FS and VS hydrogeomorphologies of rivers in the United States and Mongolia in each of three ecoregions: grassland, forest and endorheic. Fishes were collected using a backpack electrofisher, following standard protocols. Constrained ordination analyses were conducted at three scales: among continents, by continents and by individual ecoregions within continents. We found no significant difference in mean variation explained by VS versus RS or by taxonomy versus traits. Ecoregions differed in factors contributing to fish assemblage patterns, likely a result of differences in hydrogeomorphology, hydrological connectivity and historical influences. We found that fish assemblages were structured by hydrogeomorphic processes occurring at VS and RS, and that variables predicting fish assemblages varied with scale and whether fishes were classified by taxonomy or traits. Although anthropogenic impacts were substantially higher for western US rivers than for Mongolian rivers, we were unable to detect strong differences in our ability to predict fish assemblage variation from RS and VS habitat variables. [ABSTRACT FROM AUTHOR]

Mamatha, P.K.; Anil Kumar, A.; Jayappa, K.S.; Mohan, K.G.; Subhradeep Das; Anupama, L.C., and Shaniba, V., 2025. Multitemporal analysis of shoreline changes along the southwest coast of India: Inferences from geological, geomorphological, geophysical, and remote-sensing studies. Journal of Coastal Research, 41(1), 73–82. Charlotte (North Carolina), ISSN 0749-0208. In a multitemporal study of the coastal stretch between the Chandragiri and Karingotte River mouths, Kasaragod District, Kerala State, on the southwest coast of India, an interesting relationship was noticed between nearshore geological structures extending from the hinterland and the ongoing shoreline changes. An inferred structural weak plane running across the offshore domain and hinterland along the minor Chittari River divides the study area into two sectors. Seasonal- to annual-scale shoreline changes measured using beach profiles corroborate the results of decadal- to centennial-scale changes observed in remote-sensing data and millennial-scale data observed geomorphologically. On an annual to centennial scale, the shoreline on the northern part of the Chittari River manifests erosion while the counterpart on the southern side exhibits accretion. The results of millennial-scale processes revealed through geomorphology are distinct in the two sectors, where the northern part has characteristic geomorphologic features of a submerging coast, while the southern part has features of an emerging coast. Geophysical studies confirmed the presence of several structural faults and lineaments intersecting at the Chittari River mouth, and structural failures in the recent past along these fault planes confirm that this area is tectonically active. These geological structural factors stand out as the most prominent causative factors in configuring the coastline of this area when compared with other common causes of shoreline changes. [ABSTRACT FROM AUTHOR]

The document discusses the Elwha River East Delta in Washington State, USA, focusing on the impact of dam removal on the ecosystem. The removal of two large dams in the Elwha River watershed from 2011 to 2014 led to the restoration of ecosystem processes and the release of significant amounts of sediment. The study highlights the restoration efforts and challenges faced in the Elwha River and nearshore corridor following the dam removals. [Extracted from the article]

The Roman period Castrum Zerzevan is on a hill 35 km south of Diyarbakır, Türkiye. Various field evidence (e.g. petrographic similarities, sudden changes of the topographic contours, the morphology of the nearby hills, and traces of the on-site quarry activities) suggests that the topography of the hilltop was artificially modified and used as a quarry. This study aims to introduce an approach that creates the ancient topography and calculates and verifies the volume of the on-site material required to build the fortification and associated structures by applying morphological analyses. The primary objective of the methodology is to reconstruct the site's ancient topography and examine the difference between its former and present surfaces. The result indicates that approximately 36% of the extracted material was used in the enclosure. The overall findings and site investigations suggest quarrying and construction activities were carried out in a planned manner or concurrently at the site. In addition to the collected samples' petrographic and geochemical similarities, the Castrum's topographical modifications and the suitability of the geological unit as a building material support our claim that the Romans were well aware of environmental conditions (including topography and morphology) and material performance. [ABSTRACT FROM AUTHOR]