Morphological Processes and Evolution of Marine Geomorphology: Observations, Modeling and Applications

A special issue of Journal of Marine Science and Engineering (ISSN 2077-1312). This special issue belongs to the section "Geological Oceanography".

Deadline for manuscript submissions: 30 June 2025 | Viewed by 14618

Special Issue Editors


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Guest Editor
Key Laboratory of Submarine Geosciences, Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China
Interests: underwater target detection; binocular vision; semi-global stereo matching; disparity map optimization; 3D Reconstruction

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Guest Editor
Jiangsu Key Laboratory of Coastal Ocean Resources Development and Environmental Security, Hohai University, Nanjing 210024, China
Interests: estuarine and coastal geomorphology; morphological evolution; morphodynamic observation and modelling

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Guest Editor
Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering, College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
Interests: marine engineering geology; wave-seabed interactions; submarine sediment gravity flows; seafloor in situ test and observation
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Special Issue Information

Dear Colleagues,

Submarine and coastal geomorphology play a fundamental role in revealing the basic characteristics, evolution, and dynamical processes of the seafloor, serving as a foundation for submarine geosciences. From shallow coasts to the deep sea, the seafloor exhibits a wide range of forms, reflecting the influence of a range of oceanographic, sedimentary, tectonic, and biological processes on different scales of time and space. To date, only 80% of the world’s seafloor has been mapped using modern sounding technology, leaving a vast majority unexplored. Fortunately, technological advancements have significantly enhanced our ability to explore and model these environments and processes with greater accuracy. Consequently, studying the shape, processes, and evolution of coastal and submarine geomorphology has become a top priority for academic and research institutions, government authorities, and industries worldwide.

In recent years, significant progress has been made in the acquisition, processing, and interpretation of seafloor data, as well as in the development of numerical modeling methodologies. These advancements have greatly improved our understanding of coastal and submarine geomorphology and the processes that shape them. Furthermore, the availability of high-resolution spatial and temporal data has led to the application of seafloor geomorphology products in various fields. This research topic aims to provide a venue for sharing our increased knowledge on the nature of morphologic processes and evolution of coastal and submarine geomorphology. Additionally, we aim to showcase the latest techniques in observation and modeling, as well as the diverse applications of seafloor geomorphology products.

Prof. Dr. Ziyin Wu
Prof. Dr. Zeng Zhou
Prof. Dr. Xiaolei Liu
Guest Editors

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Keywords

  • coastal and submarine geomorphic processes
  • coastal and submarine geomorphic evolution
  • seafloor observation techniques
  • advances in seafloor data analysis and mining
  • modelling coastal and submarine geomorphic processes
  • applied geomorphology and geohazard assessment

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Published Papers (12 papers)

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Research

19 pages, 28456 KiB  
Article
YOLO-SG: Seafloor Topography Unit Recognition and Segmentation Algorithm Based on Lightweight Upsampling Operator and Attention Mechanisms
by Yifan Jiang, Ziyin Wu, Fanlin Yang, Dineng Zhao, Xiaoming Qin, Mingwei Wang and Qiang Wang
J. Mar. Sci. Eng. 2025, 13(3), 583; https://doi.org/10.3390/jmse13030583 - 16 Mar 2025
Viewed by 196
Abstract
The recognition and segmentation of seafloor topography play a crucial role in marine science research and engineering applications. However, traditional methods for seafloor topography recognition and segmentation face several issues, such as poor capability in analyzing complex terrains and limited generalization ability. To [...] Read more.
The recognition and segmentation of seafloor topography play a crucial role in marine science research and engineering applications. However, traditional methods for seafloor topography recognition and segmentation face several issues, such as poor capability in analyzing complex terrains and limited generalization ability. To address these challenges, this study introduces the SG-MKD dataset (Submarine Geomorphology Dataset—Seamounts, Sea Knolls, Submarine Depressions) and proposes YOLO-SG (You Only Look Once—Submarine Geomorphology), an algorithm for seafloor topographic unit recognition and segmentation that leverages a lightweight upsampling operator and attention mechanisms. The SG-MKD dataset provides instance segmentation annotations for three types of seafloor topographic units—seamounts, sea knolls, and submarine depressions—across a total of 419 images. YOLO-SG is an optimized version of the YOLOv8l-Segment model, incorporating a convolutional block attention module in the backbone network to enhance feature extraction. Additionally, it integrates a lightweight, general upsampling operator to create a new feature fusion network, thereby improving the model’s ability to fuse and represent features. Experimental results demonstrate that YOLO-SG significantly outperforms the original YOLOv8l-Segment, with a 14.7% increase in mean average precision. Furthermore, inference experiments conducted across various research areas highlight the model’s strong generalization capability. Full article
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22 pages, 16367 KiB  
Article
Enhanced Seafloor Topography Inversion Using an Attention Channel 1D Convolutional Network Based on Multiparameter Gravity Data: Case Study of the Mariana Trench
by Qiang Wang, Ziyin Wu, Zhaocai Wu, Mingwei Wang, Dineng Zhao, Taoyong Jin, Qile Zhao, Xiaoming Qin, Yang Liu, Yifan Jiang, Puchen Zhao and Ning Zhang
J. Mar. Sci. Eng. 2025, 13(3), 507; https://doi.org/10.3390/jmse13030507 - 5 Mar 2025
Viewed by 262
Abstract
Seafloor topography data are fundamental for marine resource development, oceanographic research, and maritime rights protection. However, approximately 75% of the ocean remains unsurveyed for bathymetry. Sole reliance on shipborne measurements is insufficient for constructing a global bathymetric model within a short timeframe; consequently, [...] Read more.
Seafloor topography data are fundamental for marine resource development, oceanographic research, and maritime rights protection. However, approximately 75% of the ocean remains unsurveyed for bathymetry. Sole reliance on shipborne measurements is insufficient for constructing a global bathymetric model within a short timeframe; consequently, satellite altimetry-based inversion techniques are essential for filling data gaps. Recent advancements have improved the variety and quality of satellite altimetry gravity data. To leverage the complementary advantages of multiparameter gravity data, we propose a 1D convolutional neural network based on a convolutional attention module, termed the Attention Channel 1D Convolutional Network (AC1D). Results of a case study of the Mariana Trench indicated that the AC1D grid predictions exhibited improved agreement with single-beam depth checkpoints, with standard deviation reductions of 6.32%, 20.79%, and 36.77% and root mean square error reductions of 7.11%, 22.82%, and 50.99% compared with those of parallel linked backpropagation, the gravity–geological method, and a convolutional neural network, respectively. The AC1D grid demonstrated enhanced stability in multibeam bathymetric validation metrics and exhibited better consistency with multibeam bathymetry data and the GEBCO2023 grid. Power spectral density analysis revealed that AC1D effectively captured rich topographic signals when predicting terrain features with wavelengths below 6.33 km. Full article
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23 pages, 25801 KiB  
Article
A Large-Scale Focused Fluid Flow Zone Between Atolls in the Xisha Islands (South China Sea): Types, Characteristics, and Evolution
by Jixiang Zhao, Benjun Ma, Zhiliang Qin, Wenjian Lan, Benyu Zhu, Shuyi Pang, Mingzhe Li and Ruining Wang
J. Mar. Sci. Eng. 2025, 13(2), 216; https://doi.org/10.3390/jmse13020216 - 23 Jan 2025
Viewed by 514
Abstract
A large number of seabed depressions, covering an area of 2500 km2 in the Xisha Massif of the South China Sea, are investigated using newly collected high-resolution acoustic data. By analyzing the morphological features and seismic attributes of the focused fluid flow [...] Read more.
A large number of seabed depressions, covering an area of 2500 km2 in the Xisha Massif of the South China Sea, are investigated using newly collected high-resolution acoustic data. By analyzing the morphological features and seismic attributes of the focused fluid flow system, five geological structures are recognized and described in detail, including pockmarks, volcanic mounds, pipes, faults, and forced folds. Pockmarks and volcanic mounds occur as clustered groups and their distributions are related to two large-scale volcanic zones with chaotic seismic reflections. Pipes, characterized by disordered seismic reflections, mainly occur within the focused fluid flow zone (FFFZ) and directly link with the large-scale deep volcano and its surrounding areas. Faults and fractures mainly occur along pipes and extend to the seafloor, commonly presenting lateral walls of mega-pockmarks. Forced folds are primarily clustered above volcanic zones and commonly restricted between faults or pipes, characterized by sediment deformations as indicated in seismic profiles. By comprehensive analysis of the above observations and a simplified simulation model, the volcanism-induced hydrothermal fluid activities are argued herein to contribute to these focused fluid flow structures. In addition, traces of suspected submarine instability disasters such as landslides have been found in this sea area, and more observational data will be needed to determine whether seafloor fluid flow zones can be used as a predictor of seafloor instability in the future. Full article
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25 pages, 9679 KiB  
Article
Seasonal and Inter-Annual Shoreline Dynamics Along Tam Tien Beach, Central Vietnam: Insights from Satellite Imagery Analysis
by Tran Thi Hoai Phuong, Dinh Nhat Quang, Nguyen Trung Viet and Masatoshi Yuhi
J. Mar. Sci. Eng. 2024, 12(12), 2179; https://doi.org/10.3390/jmse12122179 - 28 Nov 2024
Viewed by 746
Abstract
The shoreline of Quang Nam province in Central Vietnam has been experiencing persistent erosion, posing a significant threat to coastal communities and their livelihoods. This study analyzes eight years of Landsat-7/8/9 and Sentinel-2 images to examine shoreline changes along Tam Tien Beach in [...] Read more.
The shoreline of Quang Nam province in Central Vietnam has been experiencing persistent erosion, posing a significant threat to coastal communities and their livelihoods. This study analyzes eight years of Landsat-7/8/9 and Sentinel-2 images to examine shoreline changes along Tam Tien Beach in Quang Nam during the period 2015–2022, identifying patterns of erosion and deposition. The analysis of 75 transects over an 11 km stretch of sandy shoreline revealed that approximately 84% of the transects exhibited erosion, with transects 44 to 60 showing significant retreat of shoreline averaging around 2.5 m/year. The results also demonstrated a significant seasonal variability related to monsoon regimes. The translational and rotational shift of the shoreline was examined, and the influence of wave energy flux and wave direction were clarified. The study also applied Empirical Orthogonal Eigenfunction analysis to explore the relationship between shoreline translation, rotation, and rate of change. Under the expected future climate change, the study also underlines the vulnerability of Central Vietnam to severe erosion events. These findings are the key to predicting coastal impacts, designing effective protection structures, mitigating erosion, and managing coastal resources. Full article
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19 pages, 14188 KiB  
Article
Modeling the Impacts of Land Reclamation on Sediment Dynamics in a Semi-Enclosed Bay
by Yi Zhong, Jun Du, Yongzhi Wang, Ping Li, Guoqiang Xu, Hongbin Miu, Peiyu Zhang, Shenghui Jiang and Wei Gao
J. Mar. Sci. Eng. 2024, 12(9), 1633; https://doi.org/10.3390/jmse12091633 - 13 Sep 2024
Cited by 1 | Viewed by 1193
Abstract
Semi-enclosed bays are significantly influenced by the interactions between land and sea, as well as human activities. One notable human activity, land reclamation, impacts water exchange within these bays. However, the variability of sediment transport and cross-bay transport following reclamation remains poorly understood. [...] Read more.
Semi-enclosed bays are significantly influenced by the interactions between land and sea, as well as human activities. One notable human activity, land reclamation, impacts water exchange within these bays. However, the variability of sediment transport and cross-bay transport following reclamation remains poorly understood. This study aims to enhance the understanding of sediment dynamics and the responses of cross-bay transport to reclamation. A well-validated three-dimensional numerical model was developed in the Laizhou Bay (LB). Following reclamation, tidal currents suspended sediment concentration, and erosion increased seaward, while these factors decreased landward. In LB, surface and bottom subtidal currents flowed in opposite directions, with the direction of volume transport primarily determined by bottom currents. In the western LB, volume and sediment transport exhibited an anticyclonic pattern, with pronounced seasonal variations observed elsewhere. During summer, volume and sediment transport predominantly occurred from the northeast to the southwest. In winter, volume transport in northern LB was directed westward, while it was eastward in the southern part; sediment transport was primarily eastward. Advection played a significant role in sediment transport dynamics. The pathway of cross-bay sediment transport was primarily located in the central part of the bay. Notably, the cross-bay sediment transport flux in winter was approximately 3.5 times greater than in summer, with reclamation resulting in a reduction in cross-bay transport flux by about 22.17%. Full article
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26 pages, 13378 KiB  
Article
Empirical Orthogonal Function Analysis on Long-Term Profile Evolution of Tidal Flats along a Curved Coast in the Qiantang River Estuary, China
by Ying Li and Dongzi Pan
J. Mar. Sci. Eng. 2024, 12(7), 1089; https://doi.org/10.3390/jmse12071089 - 27 Jun 2024
Cited by 1 | Viewed by 1016
Abstract
Abstract: Tidal flats are dynamic coastal ecosystems continually reshaped by natural processes and human activities. This study investigates the application of Empirical Orthogonal Function (EOF) analysis to the long-term profile evolution of tidal flats along the Jiansan Bend of the Qiantang River Estuary, [...] Read more.
Abstract: Tidal flats are dynamic coastal ecosystems continually reshaped by natural processes and human activities. This study investigates the application of Empirical Orthogonal Function (EOF) analysis to the long-term profile evolution of tidal flats along the Jiansan Bend of the Qiantang River Estuary, China. By applying EOF analysis to profiles observed from 1984 to 2023, this study identifies dominant modes of variability and their spatial and temporal characteristics, offering insights into the complex sediment transport and morphological evolution processes. EOF analysis helps unravel the complex interactions between natural and anthropogenic factors shaping tidal flats, with the first three eigenfunctions accounting for over 90% of the observed variance. The first spatial eigenfunction captures the primary trend, while the subsequent two eigenfunctions reveal secondary and tertiary modes of variability. A conceptual model developed in this study elucidates the interplay between hydrodynamic forces and morphological changes, highlighting the rotation and oscillation of tidal flat profiles in response to seasonal variations in hydrological conditions. The findings emphasize the effectiveness of EOF analysis in capturing significant geomorphological processes and underscore its potential in enhancing the understanding of tidal flat dynamics, thereby informing more effective management and conservation strategies for these critical coastal environments. Full article
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19 pages, 62150 KiB  
Article
Characteristics and Environmental Indications of Grain Size and Magnetic Susceptibility of the Late Quaternary Sediments from the Xiyang Tidal Channel, Western South Yellow Sea
by Fei Xia, Dezheng Liu and Yongzhan Zhang
J. Mar. Sci. Eng. 2024, 12(5), 699; https://doi.org/10.3390/jmse12050699 - 24 Apr 2024
Viewed by 1685
Abstract
To reveal the characteristics and environmental indications for the combination of the grain size and magnetic susceptibility of coastal sediments, we provided a necessary basis for further study on their genetic mechanisms. Based on the data of grain size and magnetic susceptibility of [...] Read more.
To reveal the characteristics and environmental indications for the combination of the grain size and magnetic susceptibility of coastal sediments, we provided a necessary basis for further study on their genetic mechanisms. Based on the data of grain size and magnetic susceptibility of the 36.10 m long core 07SR01 sediments in the Xiyang tidal channel of western South Yellow Sea, we analyzed their variations and correlations and further revealed their environmental indications and corresponding regional sedimentary evolution via the combination of the aforementioned analysis results, the reinterpretation results of the sedimentary sequence and the age of core 07SR01 and shallow seismic profiles, and the findings of climate and glacial–eustatic cycles during Late Quaternary. The three stages of the sedimentary evolution of the Xiyang tidal channel between marine isotope stage (MIS) 7 and MIS 5 were summarized as follows: First is the stage of marginal bank and riverbed developments in the tidal estuary under a relatively high sea level and strong hydrodynamic conditions during MIS 7 (core section: 36.10–26.65 m). The sediments deposited in this stage were mainly affected by the paleo-Changjiang River and characterized by a coarse grain size (mean: 4.02 Φ) and relatively high magnetic susceptibilities (mean: 27.06 × 10−8 m3·kg−1), with small fluctuations which were strongly and positively correlated with the sand component. Second is the stage dominated by fluviolacustrine and littoral environments with the weak hydrodynamics during MIS 6–5, in which the climate changed from cold and dry to warm and humid as the sea level rose after a drop (core section: 26.65–15.77 m). The sediments deposited in this stage were characterized by a fine grain size (mean: 5.27 Φ) and low magnetic susceptibilities with minor variations (mean: 10.83 × 10−8 m3·kg−1) which were weakly and positively correlated with the coarse silt component. Third is the stage of delta front in the tidal estuary with a relatively high sea level and strong hydrodynamics during MIS 5 (core section: 15.77–0 m). The sediments deposited in this stage were strongly influenced by the paleo-Yellow River and characterized by a relatively coarse grain size (mean: 4.86 Φ), and high magnetic susceptibilities (mean: 37.15 × 10−8 m3·kg−1) with large fluctuations which were weakly and positively correlated with the sand and coarse silt components. Full article
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19 pages, 5345 KiB  
Article
Tidal Flat Erosion Processes and Their Dynamic Mechanisms on the South Side of Sheyang River Estuary, Jiangsu Province
by Wangze Zhang, Kai Ouyang, Xiaofei Zhang, Aijun Wang, Qian Yu, Xiang Ye and Caihua Yao
J. Mar. Sci. Eng. 2024, 12(4), 687; https://doi.org/10.3390/jmse12040687 - 22 Apr 2024
Cited by 3 | Viewed by 1564
Abstract
Tidal flats are accumulations of fine-grained sediment formed under the action of tides and play a very important role in coastal protection. The northern part of Jiangsu coast, as a typical example of muddy coasts found all over the world, has experienced serious [...] Read more.
Tidal flats are accumulations of fine-grained sediment formed under the action of tides and play a very important role in coastal protection. The northern part of Jiangsu coast, as a typical example of muddy coasts found all over the world, has experienced serious erosion since the Yellow River shifted northward, and the range of erosion has been gradually extending southward, now reaching the south of the Sheyang River estuary (SYRE). In order to address coastal erosion near the SYRE through protective measures, there is an urgent need for research on the spatial and temporal variation of coastal erosion processes and their control mechanisms in the SYRE and adjacent coastal areas. For this study, the tidal flats on the south side of the SYRE were selected as the study area, and the sediment dynamics in the upper and lower intertidal flat were observed in different seasons to investigate the erosion processes and their dynamic mechanisms. The results show that the tidal current and wave action in the observed intertidal flats are stronger in winter than in summer, and these intertidal flats erode under the combined action of waves and currents. During winter, the net transport of the near-bottom suspended sediment and bedload is primarily towards the southeast, while in summer, the direction tends toward the north and northeast. The net transport fluxes are larger in the lower part of the intertidal flat than in the upper part in summer and also larger in winter than in summer within the lower intertidal flat. Furthermore, the tidal flat erosion in the study area manifests as shoreline retreat and flat surface erosion. The average shoreline retreat rate increased from 23.3 m/a during 2014–2019 to 43.5 m/a during 2019–2021, and the average erosion depth of the lower and upper parts of the intertidal flat over a tidal cycle is, respectively, 1.98 cm and 0.24 cm in winter and 1.65 cm and 0.26 cm in summer. The ratio of the wave-induced bottom shear stress to the tidal current-induced bottom shear stress is 0.40~0.46 in the lower intertidal flat and increases to 0.66~0.67 in the upper intertidal flat, indicating that the intertidal flat erosion in the study area is primarily driven by tidal currents, with significant contributions from wave action, especially in the upper intertidal flat. Full article
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17 pages, 15630 KiB  
Article
Submarine Morphological Description of the Ancient Archipelagic Aprons in the Marcus–Wake Seamount Group, Northwestern Pacific Ocean
by Xiao Wang, Huaiming Li, Yongshou Cheng, Pengfei Yao, Fengyou Chu, Weilin Ma, Hongyi Wang, Shihui Lv, Xiaohu Li, Zhenggang Li, Weiyan Zhang and Yanhui Dong
J. Mar. Sci. Eng. 2024, 12(4), 670; https://doi.org/10.3390/jmse12040670 - 18 Apr 2024
Cited by 1 | Viewed by 1658
Abstract
Herein, the morphological characteristics of submarine archipelagic aprons were presented for five guyots, Suda, Arnold, Lamont, Niulang, and Zhinyv, which are over 80 Ma years old and are located in the Marcus–Wake seamount group, northwestern Pacific Ocean. Nearly 28 landslide deposits were recognized [...] Read more.
Herein, the morphological characteristics of submarine archipelagic aprons were presented for five guyots, Suda, Arnold, Lamont, Niulang, and Zhinyv, which are over 80 Ma years old and are located in the Marcus–Wake seamount group, northwestern Pacific Ocean. Nearly 28 landslide deposits were recognized using the bathymetry and backscatter intensity data collected from the studied guyots. Landslides and their deposits that surround seamounts are mostly related to the morphology of debris avalanches, scarps, gullies/channels, and bedforms. The morphology of the archipelagic aprons of the studied guyots indicates mutual landslide processes, including slump and distinct debris avalanches arising from a cohesive or cohesionless landslide material flow. The superimposition of debris flows and sedimentation dominates the recent stages of the studied guyots. The archipelagic aprons corresponding to convex-arc-shaped scarps exhibit larger domains compared to the invagination-arc-shaped scarps with similar lateral lengths. The scarp morphologies of the studied guyots are predominantly of the complex-arc shape, indicating multiple landslide events. Parallel and convergent gullies and channels are mostly found on the elongated landslide deposits, whereas divergent and radial gullies and channels are mostly distributed on the fan-shaped aprons. Ubiquitous sediment waves occurred on the bedforms of the distal archipelagic apron across the studied guyots because of sediment creep. Small-scale sediment waves were only observed in the channels on the aprons of the Suda guyot. Full article
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16 pages, 24700 KiB  
Article
Teleseismic Indication of Magmatic and Tectonic Activities at Slow- and Ultraslow-Spreading Ridges
by Kaixuan Yan, Jie Chen and Tao Zhang
J. Mar. Sci. Eng. 2024, 12(4), 605; https://doi.org/10.3390/jmse12040605 - 30 Mar 2024
Viewed by 1187
Abstract
Magmatic and tectonic processes in the formation of oceanic lithosphere at slow–ultraslow-spreading mid-ocean ridges (MORs) are more complicated relative to faster-spreading ridges, as their melt flux is overall low, with highly spatial and temporal variations. Here, we use the teleseismic catalog of magnitudes [...] Read more.
Magmatic and tectonic processes in the formation of oceanic lithosphere at slow–ultraslow-spreading mid-ocean ridges (MORs) are more complicated relative to faster-spreading ridges, as their melt flux is overall low, with highly spatial and temporal variations. Here, we use the teleseismic catalog of magnitudes over 4 between 1995 and 2020 from the International Seismological Center to investigate the characteristics of magmatic and tectonic activities at the ultraslow-spreading Southwest Indian Ridge and Arctic Gakkel Ridge and the slow-spreading North Mid-Atlantic Ridge and Carlsberg Ridge (total length of 14,300 km). Using the single-link cluster analysis technique, we identify 78 seismic swarms (≥8 events), 877 sequences (2–7 events), and 3543 single events. Seismic swarms often occur near the volcanic center of second-order segments, presumably relating to relatively robust magmatism. By comparing the patterns of seismicity between ultraslow- and slow-spreading ridges, and between melt-rich and melt-poor regions of the Southwest Indian Ridge with distinct seafloor morphologies, we demonstrate that a lower spreading rate and a lower melt supply correspond to a higher seismicity rate and a higher potential of large volcano-induced seismic swarms, probably due to a thicker and colder lithosphere with a higher degree of along-axis melt focusing there. Full article
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19 pages, 35252 KiB  
Article
Erosional and Depositional Features along the Axis of a Canyon in the Northern South China Sea and Their Implications: Insights from High-Resolution AUV-Based Geophysical Data
by Xishuang Li, Lejun Liu, Bigui Huang, Qingjie Zhou and Chengyi Zhang
J. Mar. Sci. Eng. 2024, 12(4), 599; https://doi.org/10.3390/jmse12040599 - 30 Mar 2024
Viewed by 1225
Abstract
Autonomous Underwater Vehicle (AUV)-based multibeam bathymetry, sub-bottom profiles, and side-scan sonar images were collected in 2009 and 2010 to map the geomorphic features along the axial zone of a canyon (referred to as C4) within the canyon system developed on the northern slope [...] Read more.
Autonomous Underwater Vehicle (AUV)-based multibeam bathymetry, sub-bottom profiles, and side-scan sonar images were collected in 2009 and 2010 to map the geomorphic features along the axial zone of a canyon (referred to as C4) within the canyon system developed on the northern slope of the South China Sea. These data significantly improved the spatial resolution of acoustic data, leading to a better understanding of the sedimentary processes within the modern canyon system. The bathymetric data reveal that sections across the canyon axis exhibit either asymmetrical or symmetrical characteristics, which differ from the overall asymmetrical pattern of the entire canyon. This suggests that the overall asymmetrical pattern of the canyon is not primarily due to axial incision. Various morphological elements were identified along the canyon axis, including failure scars, undulating features, knickpoints, flat terraces, furrows, and mass transport deposits (MTDs). Landslides, predominantly located in the upper canyon, were formed after at least 5000 years BP. Between the beginning of the canyon and a water depth of approximately 1300 m, there are alternating flat terraces and knickpoints. The large knickpoints’ low slope gradients are likely formed by the presence of undulating features. The internal configurations of undulating features suggest that they are depositional structures rather than sediment deformation. The formation of small-scale furrows below a depth of 1200 m may be associated with occasional gravity flows down the canyon. It is suggested that the canyon was generally inactive during the Holocene but experienced sporadic processes of sediment erosion, transport, and re-deposition in the axial zone that were triggered by landslide events occasionally in the upper canyon. Full article
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12 pages, 8148 KiB  
Article
Multi-Module Fusion Model for Submarine Pipeline Identification Based on YOLOv5
by Bochen Duan, Shengping Wang, Changlong Luo and Zhigao Chen
J. Mar. Sci. Eng. 2024, 12(3), 451; https://doi.org/10.3390/jmse12030451 - 3 Mar 2024
Cited by 2 | Viewed by 1678
Abstract
In recent years, the surge in marine activities has increased the frequency of submarine pipeline failures. Detecting and identifying the buried conditions of submarine pipelines has become critical. Sub-bottom profilers (SBPs) are widely employed for pipeline detection, yet manual data interpretation hampers efficiency. [...] Read more.
In recent years, the surge in marine activities has increased the frequency of submarine pipeline failures. Detecting and identifying the buried conditions of submarine pipelines has become critical. Sub-bottom profilers (SBPs) are widely employed for pipeline detection, yet manual data interpretation hampers efficiency. The present study proposes an automated detection method for submarine pipelines using deep learning models. The approach enhances the YOLOv5s model by integrating Squeeze and Excitation Networks (SE-Net) and S2-MLPv2 attention modules into the backbone network structure. The Slicing Aided Hyper Inference (SAHI) module is subsequently introduced to recognize original large-image data. Experimental results conducted in the Yellow Sea region demonstrate that the refined model achieves a precision of 82.5%, recall of 99.2%, and harmonic mean (F1 score) of 90.0% on actual submarine pipeline data detected using an SBP. These results demonstrate the efficiency of the proposed method and applicability in real-world scenarios. Full article
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